Descriptor: "MESH: Brain Mapping" - Searchworks@Jio Institute Digital Library Search Results

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288 results on '"MESH: Brain Mapping"'

151. Arousal and valence effects on event-related P3a and P3b during emotional categorization

Author: Laetitia Silvert, Henrique Sequeira, Sylvain Delplanque, Pascal Hot, Simon Rigoulot, Laboratoire de psychologie sociale et de psychologie cognitive (LAPSCO), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Neurosciences Fonctionnelles et Pathologies (LNFP), and Université de Lille, Droit et Santé-Centre National de la Recherche Scientifique (CNRS)
Subjects: Electroencephalography/methods, Emotions, MESH: Cognition, Evoked Potentials/physiology, Cognition, 0302 clinical medicine, Arousal/physiology, Evoked Potentials, Cognition/physiology, MESH: Brain Mapping, Brain Mapping, General Neuroscience, 05 social sciences, Electroencephalography, MESH: Evoked Potentials, Neuropsychology and Physiological Psychology, MESH: Photic Stimulation, Categorization, Reaction Time/physiology, [SCCO.PSYC]Cognitive science/Psychology, Female, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Arousal, Psychology, Cognitive psychology, Adult, Stimulus (physiology), 050105 experimental psychology, 03 medical and health sciences, P3a, Physiology (medical), MESH: Analysis of Variance, Negativity bias, P3b, MESH: Electroencephalography, Reaction Time, Humans, 0501 psychology and cognitive sciences, Valence (psychology), MESH: Emotions, Analysis of Variance, MESH: Humans, MESH: Arousal, MESH: Adult, MESH: Reaction Time, Emotions/physiology, MESH: Female, Photic Stimulation, 030217 neurology & neurosurgery, Photic Stimulation/methods
Abstract: International audience; Due to the adaptive value of emotional situations, categorizing along the valence dimension may be supported by critical brain functions. The present study examined emotion-cognition relationships by focusing on the influence of an emotional categorization task on the cognitive processing induced by an oddball-like paradigm. Event-related potentials (ERPs) were recorded from subjects explicitly asked to categorize along the valence dimension (unpleasant, neutral or pleasant) deviant target pictures embedded in a train of standard stimuli. Late positivities evoked in response to the target pictures were decomposed into a P3a and a P3b and topographical differences were observed according to the valence content of the stimuli. P3a showed enhanced amplitudes at posterior sites in response to unpleasant pictures as compared to both neutral and pleasant pictures. This effect is interpreted as a negativity bias related to attentional processing. The P3b component was sensitive to the arousal value of the stimulation, with higher amplitudes at several posterior sites for both types of emotional pictures. Moreover, unpleasant pictures evoked smaller amplitudes than pleasant ones at fronto-central sites. Thus, the context updating process may be differentially modulated by the affective arousal and valence of the stimulus. The present study supports the assumption that, during an emotional categorization, the emotional content of the stimulus may modulate the reorientation of attention and the subsequent updating process in a specific way.
Published: 2006
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152. Cognitive inhibition of number/length interference in a Piaget-like task in young adults: evidence from ERPs and fMRI

Author: Stéphanie Dubal, Marc Joliot, Gaëlle Leroux, Bernard Mazoyer, Nathalie Tzourio-Mazoyer, Olivier Houdé, Groupe d'imagerie neurofonctionnelle (GIN), Institut des Maladies Neurodégénératives [Bordeaux] (IMN), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Vulnérabilité Adaptation et Psychopathologie (VAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Groupe d'imagerie neuro-fonctionnelle (GIN - UMR 6194), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université Paris Descartes - Paris 5 (UPD5)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre-Imagerie, Neurosciences, et Application aux Pathologies (CI-NAPS - UMR 6232), Normandie Université (NU)-Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Descartes - Paris 5 (UPD5)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche en neurosciences de Lyon (CRNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Groupe d'Imagerie Neurofonctionnelle (GIN - UMR 5296), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)-Service NEUROSPIN (NEUROSPIN), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de psychologie du développement et de l'éducation de l'enfant (LaPsyDÉ - UMR 8240), Normandie Université (NU)-Normandie Université (NU)-Université Paris Descartes - Paris 5 (UPD5)-Centre National de la Recherche Scientifique (CNRS), Groupe d'imagerie neuro-fonctionnelle ( GIN - UMR 6194 ), Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Université Paris Descartes - Paris 5 ( UPD5 ) -Centre National de la Recherche Scientifique ( CNRS ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Centre-Imagerie, Neurosciences, et Application aux Pathologies ( CI-NAPS - UMR 6232 ), Normandie Université ( NU ) -Normandie Université ( NU ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris Descartes - Paris 5 ( UPD5 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Vulnérabilité Adaptation et Psychopathologie ( VAP ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ), Institut Universitaire de France ( IUF ), Ministère de l'Éducation nationale, de l’Enseignement supérieur et de la Recherche ( M.E.N.E.S.R. ), Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 ( PhLAM ), and Université de Lille-Centre National de la Recherche Scientifique ( CNRS )
Subjects: Male, MESH: Evoked Potentials, Visual, MESH : Brain Mapping, MESH: Cognition, Electroencephalography, Task (project management), MESH: Magnetic Resonance Imaging, Cognition, 0302 clinical medicine, Cortex (anatomy), Cognitive development, MESH : Female, Young adult, ComputingMilieux_MISCELLANEOUS, Research Articles, MESH: Brain Mapping, Temporal cortex, Brain Mapping, number, Radiological and Ultrasound Technology, medicine.diagnostic_test, 05 social sciences, Brain, event-related potential (ERP), MESH: Neural Inhibition, MESH : Adult, Magnetic Resonance Imaging, visuospatial interference, MESH : Evoked Potentials, Visual, inhibition, medicine.anatomical_structure, Cognitive inhibition, Neurology, MESH : Cognition, Female, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Anatomy, Psychology, Adult, MESH : Male, Piaget-like task, 050105 experimental psychology, 03 medical and health sciences, MESH: Brain, MESH : Magnetic Resonance Imaging, Reaction Time, medicine, Humans, 0501 psychology and cognitive sciences, Radiology, Nuclear Medicine and imaging, MESH: Humans, [SCCO.NEUR]Cognitive science/Neuroscience, MESH : Humans, functional magnetic resonance imaging (fMRI), Neural Inhibition, MESH: Adult, MESH: Male, MESH: Reaction Time, Functional imaging, MESH : Brain, MESH : Reaction Time, [ SDV.NEU ] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Evoked Potentials, Visual, Neurology (clinical), MESH: Female, Neuroscience, 030217 neurology & neurosurgery, MESH : Neural Inhibition
Abstract: We sought to determine whether the neural traces of a previous cognitive developmental stage could be evidenced in young adults. In order to do so, 12 young adults underwent two functional imaging acquisitions (EEG then fMRI). During each session, two experimental conditions were applied: a Piaget‐like task with number/length interference (INT), and a reference task with number/length covariation (COV). To succeed at Piaget's numerical task, which children under the age of 7 years usually fail, the subjects had to inhibit a misleading strategy, namely, the visuospatial length‐equals‐number bias, a quantification heuristic that is often relevant and that continues to be used through adulthood. Behavioral data confirmed that although there was an automation in the young adult subjects as assessed by the very high number of accurate responses (>97%), the inhibition of the “length equals number strategy” had a cognitive cost, as the reaction times were significantly higher in INT than in COV (with a difference of 230 ms). The event‐related potential results acquired during the first session showed electrophysiological markers of the cognitive inhibition of the number/length interference. Indeed, the frontal N2 was greater during INT than during COV, and a P3(late)/P6 was detected only during INT. During the fMRI session, a greater activation of unimodal areas (the right middle and superior occipital cortex) and in the ventral route (the left inferior temporal cortex) was observed in INT than in COV. These results seem to indicate that when fully automated in adults, inhibition processes might take place in unimodal areas. Hum Brain Mapp, 2005. © 2005 Wiley‐Liss, Inc.
Published: 2006
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153. Direct and fast detection of neuronal activation in the human brain with diffusion MRI

Author: Denis Le Bihan, Hidenao Fukuyama, Toshihiko Aso, Takashi Hanakawa, Shin-ichi Urayama, Service NEUROSPIN (NEUROSPIN), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Human Brain Research Center [Kyoto] (HBRC), Kyoto University [Kyoto], Service Hospitalier Frédéric Joliot (SHFJ), National Institutes of Health [Bethesda] (NIH), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Kyoto University
Subjects: Adult, Male, Time Factors, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Biophysics, MESH: Neurons, MESH: Diffusion Magnetic Resonance Imaging, Brain mapping, 030218 nuclear medicine & medical imaging, MESH: Magnetic Resonance Imaging, 03 medical and health sciences, MESH: Brain, 0302 clinical medicine, Functional neuroimaging, medicine, Humans, Water diffusion, MESH: Biophysics, MESH: Brain Mapping, Visual Cortex, Neurons, Brain Mapping, Models, Statistical, Multidisciplinary, MESH: Humans, Chemistry, Cell Membrane, MESH: Time Factors, MESH: Visual Cortex, Brain, MESH: Adult, Anatomy, Human brain, Biological Sciences, Magnetic Resonance Imaging, Neuronal activation, MESH: Male, Diffusion Magnetic Resonance Imaging, Visual cortex, medicine.anatomical_structure, Time course, Female, Neuroscience, MESH: Female, 030217 neurology & neurosurgery, MESH: Models, Statistical, Diffusion MRI, MESH: Cell Membrane
Abstract: International audience; Using MRI, we found that a slowly diffusing water pool was expanding (1.7 +/- 0.3%) upon activation on the human visual cortex at the detriment of a faster diffusing pool. The time course of this water phase transition preceded the activation-triggered vascular response detected by usual functional MRI by several seconds. The observed changes in water diffusion likely reflect early biophysical events that take place in the activated cells, such as cell swelling and membrane expansion. Although the exact mechanisms remain to clarify, access to such an early and direct physiological marker of cortical activation with MRI will provide opportunities for functional neuroimaging of the human brain.
Published: 2006
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154. Dynamics of prefrontal and cingulate activity during a reward-based logical deduction task

Author: Denis Le Bihan, Sabina Pappatà, Dimitri Roumenov, Michel Bottlaender, Antoinette Jobert, Stanislas Dehaene, Claire Landmann, Neuroimagerie cognitive (LCogn), Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Santé et de la Recherche Médicale (INSERM), Service Hospitalier Frédéric Joliot (SHFJ), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Chaire Psychologie cognitive expérimentale, Collège de France (CdF (institution)), Institutions et Dynamiques Historiques de l'Economie (IDHE), École normale supérieure - Cachan (ENS Cachan)-Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris 8 Vincennes-Saint-Denis (UP8)-Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS), Service NEUROSPIN (NEUROSPIN), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Human Brain Research Center [Kyoto] (HBRC), Kyoto University [Kyoto], National Institutes of Health [Bethesda] (NIH), Collège de France - Chaire Psychologie cognitive expérimentale, and Kyoto University
Subjects: MESH: Decision Making, Adult, Male, Deductive reasoning, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Cognitive Neuroscience, Decision Making, MESH: Evoked Potentials, Motor, Prefrontal Cortex, Gyrus Cinguli, 050105 experimental psychology, MESH: Magnetic Resonance Imaging, Developmental psychology, Task (project management), 03 medical and health sciences, Cellular and Molecular Neuroscience, 0302 clinical medicine, Reward, MESH: Gyrus Cinguli, Task Performance and Analysis, medicine, Humans, 0501 psychology and cognitive sciences, Prefrontal cortex, MESH: Brain Mapping, MESH: Reward, Brain Mapping, MESH: Humans, medicine.diagnostic_test, 05 social sciences, MESH: Adult, MESH: Task Performance and Analysis, Evoked Potentials, Motor, Magnetic Resonance Imaging, MESH: Male, Dynamics (music), MESH: Prefrontal Cortex, Functional magnetic resonance imaging, Psychology, 030217 neurology & neurosurgery, Cognitive psychology
Abstract: International audience; We used behavioral and functional magnetic resonance imaging (fMRI) methods to probe the cerebral organization of a simple logical deduction process. Subjects were engaged in a motor trial-and-error learning task, in which they had to infer the identity of an unknown 4-key code. The design of the task allowed subjects to base their inferences not only on the feedback they received but also on the internal deductions that it afforded (autoevaluation). fMRI analysis revealed a large bilateral parietal, prefrontal, cingulate, and striatal network that activated suddenly during search periods and collapsed during ensuing periods of sequence repetition. Fine-grained analyses of the temporal dynamics of this search network indicated that it operates according to near-optimal rules that include 1) computation of the difference between expected and obtained rewards and 2) anticipatory deductions that predate the actual reception of positive reward. In summary, the dynamics of effortful mental deduction can be tracked with fMRI and relate to a distributed network engaging prefrontal cortex and its interconnected cortical and subcortical regions.
Published: 2006
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155. Dynamic causal modelling of evoked responses in EEG/MEG with lead field parameterization

Author: Stefan J. Kiebel, Olivier David, Karl J. Friston, Wellcome Department of Imaging Neuroscience, University College of London [London] (UCL)-Institute of Neurology, This work was supported by the Wellcome Trust., Collaboration, and David, Olivier
Subjects: Computer science, MESH: Neurons, Electroencephalography, computer.software_genre, 0302 clinical medicine, Evoked Potentials, MESH: Brain Mapping, Causal model, Hierarchical networks, Cerebral Cortex, Neurons, Brain Mapping, medicine.diagnostic_test, MESH: Finite Element Analysis, Orientation (computer vision), 05 social sciences, Magnetoencephalography, Inverse problem, Generative model, MESH: Nonlinear Dynamics, MESH: Evoked Potentials, medicine.anatomical_structure, Neurology, Pattern Recognition, Visual, Cerebral cortex, Auditory Perception, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Algorithm, Cognitive Neuroscience, MESH: Bayes Theorem, Finite Element Analysis, MESH: Pattern Recognition, Visual, Machine learning, 050105 experimental psychology, MESH: Electromyography, 03 medical and health sciences, MESH: Auditory Perception, MESH: Neural Networks (Computer), MESH: Electroencephalography, medicine, Humans, 0501 psychology and cognitive sciences, [SDV.NEU] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Dominance, Cerebral, Equivalent current dipole, MESH: Humans, Quantitative Biology::Neurons and Cognition, business.industry, Electromyography, [SCCO.NEUR]Cognitive science/Neuroscience, [SCCO.NEUR] Cognitive science/Neuroscience, Dynamic causal modelling, Bayes Theorem, MESH: Dominance, Cerebral, Expression (mathematics), MESH: Cerebral Cortex, MESH: Nerve Net, Nonlinear dynamics, Artificial intelligence, Neural Networks, Computer, Nerve Net, business, computer, 030217 neurology & neurosurgery
Abstract: International audience; Dynamical causal modeling (DCM) of evoked responses is a new approach to making inferences about connectivity changes in hierarchical networks measured with electro- and magnetoencephalography (EEG and MEG). In a previous paper, we illustrated this concept using a lead field that was specified with infinite prior precision. With this prior, the spatial expression of each source area, in the sensors, is fixed. In this paper, we show that using lead field parameters with finite precision enables the data to inform the network's spatial configuration and its expression at the sensors. This means that lead field and coupling parameters can be estimated simultaneously. Alternatively, one can also view DCM for evoked responses as a source reconstruction approach with temporal, physiologically informed constraints. We will illustrate this idea using, for each area, a 4-shell equivalent current dipole (ECD) model with three location and three orientation parameters. Using synthetic and real data, we show that this approach furnishes accurate and robust conditional estimates of coupling among sources and their orientations.
Published: 2006
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156. Dynamic causal modeling of evoked responses in EEG and MEG

Author: James M. Kilner, Stefan J. Kiebel, Lee M. Harrison, Jérémie Mattout, Karl J. Friston, Olivier David, Wellcome Department of Imaging Neuroscience, Functional Imaging Laboratory, Institute of Neurology, and David, Olivier
Subjects: magnetoencephalography, MESH: Magnetoencephalography, Auditory Pathways, MESH: Neurons, Mismatch negativity, Inference, computer.software_genre, Synaptic Transmission, Bayes' theorem, 0302 clinical medicine, MESH: Pitch Perception, Pitch Perception, Evoked Potentials, MESH: Brain Mapping, Causal model, Cerebral Cortex, Neurons, 0303 health sciences, Brain Mapping, medicine.diagnostic_test, and Bayesian inference, Electroencephalography, neural networks, MESH: Nonlinear Dynamics, MESH: Evoked Potentials, Neurology, Pattern Recognition, Visual, MESH: Auditory Pathways, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Psychology, Cognitive Neuroscience, MESH: Bayes Theorem, Bayesian probability, causal modeling, MESH: Pattern Recognition, Visual, Bayesian inference, Machine learning, 03 medical and health sciences, nonlinear dynamics, MESH: Neural Networks (Computer), MESH: Electroencephalography, medicine, MESH: Synaptic Transmission, Humans, Visual Pathways, [SDV.NEU] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], 030304 developmental biology, MESH: Visual Pathways, MESH: Humans, business.industry, Dynamic causal modelling, Bayes Theorem, Magnetoencephalography, MESH: Cerebral Cortex, MESH: Nerve Net, Artificial intelligence, Neural Networks, Computer, Nerve Net, business, computer, 030217 neurology & neurosurgery
Abstract: International audience; Neuronally plausible, generative or forward models are essential for understanding how event-related fields (ERFs) and potentials (ERPs) are generated. In this paper, we present a new approach to modeling event-related responses measured with EEG or MEG. This approach uses a biologically informed model to make inferences about the underlying neuronal networks generating responses. The approach can be regarded as a neurobiologically constrained source reconstruction scheme, in which the parameters of the reconstruction have an explicit neuronal interpretation. Specifically, these parameters encode, among other things, the coupling among sources and how that coupling depends upon stimulus attributes or experimental context. The basic idea is to supplement conventional electromagnetic forward models, of how sources are expressed in measurement space, with a model of how source activity is generated by neuronal dynamics. A single inversion of this extended forward model enables inference about both the spatial deployment of sources and the underlying neuronal architecture generating them. Critically, this inference covers long-range connections among well-defined neuronal subpopulations. In a previous paper, we simulated ERPs using a hierarchical neural-mass model that embodied bottom-up, top-down and lateral connections among remote regions. In this paper, we describe a Bayesian procedure to estimate the parameters of this model using empirical data. We demonstrate this procedure by characterizing the role of changes in cortico-cortical coupling, in the genesis of ERPs. In the first experiment, ERPs recorded during the perception of faces and houses were modeled as distinct cortical sources in the ventral visual pathway. Category-selectivity, as indexed by the face-selective N170, could be explained by category-specific differences in forward connections from sensory to higher areas in the ventral stream. We were able to quantify and make inferences about these effects using conditional estimates of connectivity. This allowed us to identify where, in the processing stream, category-selectivity emerged. In the second experiment, we used an auditory oddball paradigm to show that the mismatch negativity can be explained by changes in connectivity. Specifically, using Bayesian model selection, we assessed changes in backward connections, above and beyond changes in forward connections. In accord with theoretical predictions, there was strong evidence for learning-related changes in both forward and backward coupling. These examples show that category- or context-specific coupling among cortical regions can be assessed explicitly, within a mechanistic, biologically motivated inference framework.
Published: 2006
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157. When Broca experiences the Janus syndrome: an ER-fMRI study comparing sentence comprehension and cognitive sequence processing

Author: Mathilde Pachot-Clouard, Peter Ford Dominey, Christoph Segebarth, Michel Hoen, Institut des Sciences Cognitives (ISC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Dynamique Du Langage (DDL), Université Lumière - Lyon 2 (UL2)-Centre National de la Recherche Scientifique (CNRS), Neuroimagerie Fonctionnelle et Metabolique, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Collaboration, Dojat, Michel, Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)
Subjects: Male, MESH: Cognition, MESH: Frontal Lobe, MESH: Comprehension, Sentence processing, MESH: Magnetic Resonance Imaging, 0302 clinical medicine, Cognition, Cluster Analysis, MESH: Brain Mapping, Cerebral Cortex, Brain Mapping, Psycholinguistics, medicine.diagnostic_test, 05 social sciences, Magnetic Resonance Imaging, Frontal Lobe, Neuropsychology and Physiological Psychology, Female, Psychology, Comprehension, Sentence, Cognitive psychology, Adult, Elementary cognitive task, Cognitive Neuroscience, Models, Neurological, Experimental and Cognitive Psychology, MESH: Psychomotor Performance, MESH: Reading, 050105 experimental psychology, MESH: Psycholinguistics, 03 medical and health sciences, Functional neuroimaging, MESH: Models, Neurological, medicine, Humans, 0501 psychology and cognitive sciences, Broca's area, MESH: Humans, MESH: Adult, MESH: Cluster Analysis, MESH: Male, MESH: Cerebral Cortex, Reading, MESH: Nerve Net, Nerve Net, Functional magnetic resonance imaging, MESH: Female, 030217 neurology & neurosurgery, Psychomotor Performance
Abstract: International audience; The determining of brain regions that exhibit specific activity during sentence comprehension compared to other non-linguistic cognitive tasks constitutes one of the important challenges in the domain of functional neuroimaging of the faculty of language. In the current paper we report an event-related functional magnetic resonance imaging (ER-fMRI) experiment, in which we directly compared the cerebral basis of sentence comprehension on the one hand, and of abstract sequence processing on the other hand. Previous experimental work done in our group, as well as different observations from recent behavioural, neurophysiological and functional neuroimaging experiments led us to propose the hypothesis that both of these tasks would share certain computational properties. Thus, this experiment was designed to show which brain regions would be implicated in both tasks and compare them to brain regions that would be specifically engaged in sentence comprehension. Results from this experiment suggest that distinct sub-regions in the left prefrontal cortex, potentially including Broca's area show distinct activation patterns during both of these tasks. Results are discussed in the context of a construction-based model of sentence processing (see Dominey and Hoen, 2006, this issue) that is based on a dual-path processing mechanism separating function and content information processing. We propose and discuss the hypothesis that subparts of Broca's area BA 44 and BA 45 would respectively be implicated in two different aspects of sentence comprehension: i) a general structure mapping capability and ii) the online integration of semantic representations onto structural constraints.
Published: 2006
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158. Global integration of local color differences in transparency perception: An fMRI study

Author: Chantal Delon-Martin, Michel Dojat, Mathilde Pachot-Clouard, Kenneth Knoblauch, Christoph Segebarth, Loÿs Piettre, Neuroimagerie Fonctionnelle et Metabolique, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Cerveau et vision, Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-IFR19-Institut National de la Santé et de la Recherche Médicale (INSERM), and Knoblauch, Kenneth
Subjects: Male, genetic structures, Physiology, Computer science, MESH: Color Perception, MESH: Magnetic Resonance Imaging, 0302 clinical medicine, Local color, Image Processing, Computer-Assisted, Attention, MESH: Brain Mapping, media_common, Brain Mapping, Color constancy, 05 social sciences, fMRI, Brain, Magnetic Resonance Imaging, MESH: Image Processing, Computer-Assisted, Sensory Systems, medicine.anatomical_structure, MESH: Photic Stimulation, Pattern Recognition, Visual, [SDV.MHEP.OS] Life Sciences [q-bio]/Human health and pathology/Sensory Organs, Female, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Parahippocampal gyrus, Color Perception, MESH: Oxygen, Coherence (physics), Adult, Human vision, Color vision, media_common.quotation_subject, Color, Standard illuminant, MESH: Pattern Recognition, Visual, [SDV.IB.MN]Life Sciences [q-bio]/Bioengineering/Nuclear medicine, Transparency, 050105 experimental psychology, Article, [SDV.IB.MN] Life Sciences [q-bio]/Bioengineering/Nuclear medicine, 03 medical and health sciences, MESH: Brain, Perception, medicine, Humans, 0501 psychology and cognitive sciences, MESH: Form Perception, [SDV.NEU] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Chromatic scale, [SDV.MHEP.OS]Life Sciences [q-bio]/Human health and pathology/Sensory Organs, MESH: Color, Communication, MESH: Attention, MESH: Humans, Color Vision, business.industry, Pattern recognition, MESH: Adult, MESH: Male, Form Perception, Oxygen, Artificial intelligence, business, MESH: Female, 030217 neurology & neurosurgery, Photic Stimulation
Abstract: In normal viewing, the visual system effortlessly assigns approximately constant attributes of color and shape to perceived objects. A fundamental component of this process is the compensation for illuminant variations and intervening media to recover reflectance properties of natural surfaces. We exploited the phenomenon of transparency perception to explore the cortical regions implicated in such processes, using fMRI. By manipulating the coherence of local color differences around a region in an image, we interfered with their global perceptual integration and thereby modified whether the region appeared transparent or not. We found the major cortical activation due to global integration of local color differences to be in the anterior part of the parahippocampal gyrus. Regions differentially activated by chromatic versus achromatic geometric patterns showed no significant differential response related to the coherence/incoherence of local color differences. The results link the integration of local color differences in the extraction of a transparent layer with sites activated by object-related properties of an image.
Published: 2006
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159. The ventral premotor cortex (vPM) and resistance to interference

Author: Sophie Garcia, François Sellal, Muriel Boucart, George A. Michael, Damien Fernandez, Croissance cellulaire, réparation et régénération tissulaires (CRRET), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Résistance des plantes aux bio-agresseurs (UMR RPB), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université Montpellier 2 - Sciences et Techniques (UM2), Electronic Engineering Department, Universitat Politècnica de Catalunya [Barcelona] (UPC), Laboratoire de Phytopathologie Tropicale, Service de Neurologie [Strasbourg], CHU Strasbourg-Hopital Civil, Institut de Biologie du Développement de Marseille (IBDM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Neurosciences Fonctionnelles et Pathologies (LNFP), Université de Lille, Droit et Santé-Centre National de la Recherche Scientifique (CNRS), and Université Montpellier 2 - Sciences et Techniques (UM2)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)
Subjects: Male, Cognitive model, Time Factors, MESH: Brain Diseases, Frontal operculum, Interference (genetic), Task (project management), Behavioral Neuroscience, Circumscribed lesion, 0302 clinical medicine, Attention, MESH: Brain Mapping, Brain Diseases, Brain Mapping, 05 social sciences, Motor Cortex, MESH: Case-Control Studies, medicine.anatomical_structure, MESH: Photic Stimulation, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Cues, medicine.symptom, Psychology, Adult, MESH: Space Perception, MESH: Orientation, Models, Biological, behavioral disciplines and activities, MESH: Motor Cortex, 050105 experimental psychology, Premotor cortex, Lesion, 03 medical and health sciences, Orientation, Reaction Time, medicine, Humans, Visual attention, 0501 psychology and cognitive sciences, MESH: Attention, MESH: Humans, MESH: Time Factors, MESH: Models, Biological, MESH: Adult, MESH: Male, MESH: Reaction Time, Case-Control Studies, Space Perception, Neuroscience, Photic Stimulation, 030217 neurology & neurosurgery, MESH: Cues
Abstract: International audience; The authors tested a patient suffering from a circumscribed lesion of the right frontal operculum (FO) in 3 experiments of visual attention involving spatial orienting, maintenance of task-relevant priorities, and control of interference from new and old task-irrelevant items. The authors found that spatial orienting and active maintenance of priorities were intact, but there were difficulties in controlling interference from new and old irrelevant items. These results suggest that the FO is necessary for the direct control of interference, but its lesion alone is not enough to disturb spatial orienting processes or active maintenance of task priorities. The authors discuss the results in light of a hybrid cognitive model of attention.
Published: 2006
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160. A model for integrating elementary neural functions into delayed-response behavior

Author: Thomas Gisiger, Michel Kerszberg, Récepteurs et Cognition (RC), Collège de France (CdF (institution))-Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Modélisation dynamique des systèmes intégrés, Systématique, adaptation, évolution (SAE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Collège de France (CdF (institution))-Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS)
Subjects: Brain activity and meditation, Computer science, Basal Ganglia, MESH: Basal Ganglia, 0302 clinical medicine, Prospective memory, Psychology, MESH: Animals, Prefrontal cortex, lcsh:QH301-705.5, MESH: Haplorhini, MESH: Brain Mapping, 0303 health sciences, Brain Mapping, MESH: Electrophysiology, Artificial neural network, Animal Behavior, Ecology, Brain, Haplorhini, [SDV.BIBS]Life Sciences [q-bio]/Quantitative Methods [q-bio.QM], Electrophysiology, Memory, Short-Term, Computational Theory and Mathematics, Modeling and Simulation, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Bioinformatics - Computational Biology, Algorithms, Research Article, Primates, Elementary cognitive task, Models, Neurological, Prefrontal Cortex, MESH: Algorithms, MESH: Memory, Short-Term, 03 medical and health sciences, Cellular and Molecular Neuroscience, MESH: Brain, MESH: Computer Simulation, MESH: Models, Neurological, None, Genetics, Animals, Humans, Learning, Computer Simulation, Set (psychology), Molecular Biology, Ecology, Evolution, Behavior and Systematics, 030304 developmental biology, MESH: Humans, Working memory, Network dynamics, lcsh:Biology (General), MESH: Nerve Net, MESH: Prefrontal Cortex, MESH: Learning, Nerve Net, Neuroscience, 030217 neurology & neurosurgery
Abstract: It is well established that various cortical regions can implement a wide array of neural processes, yet the mechanisms which integrate these processes into behavior-producing, brain-scale activity remain elusive. We propose that an important role in this respect might be played by executive structures controlling the traffic of information between the cortical regions involved. To illustrate this hypothesis, we present a neural network model comprising a set of interconnected structures harboring stimulus-related activity (visual representation, working memory, and planning), and a group of executive units with task-related activity patterns that manage the information flowing between them. The resulting dynamics allows the network to perform the dual task of either retaining an image during a delay (delayed-matching to sample task), or recalling from this image another one that has been associated with it during training (delayed-pair association task). The model reproduces behavioral and electrophysiological data gathered on the inferior temporal and prefrontal cortices of primates performing these same tasks. It also makes predictions on how neural activity coding for the recall of the image associated with the sample emerges and becomes prospective during the training phase. The network dynamics proves to be very stable against perturbations, and it exhibits signs of scale-invariant organization and cooperativity. The present network represents a possible neural implementation for active, top-down, prospective memory retrieval in primates. The model suggests that brain activity leading to performance of cognitive tasks might be organized in modular fashion, simple neural functions becoming integrated into more complex behavior by executive structures harbored in prefrontal cortex and/or basal ganglia., Synopsis Before we do anything, our brain must construct neural representations of the operations required. Imaging and recording techniques are indeed providing ever more detailed insight into how different regions of the brain contribute to behavior. However, it has remained elusive exactly how these various regions then come to cooperate with each other, thus organizing the brain-scale activity patterns needed for even the simplest planned tasks. In the present work, the authors propose a neural network model built around the hypothesis of a modular organization of brain activity, where relatively autonomous basic neural functions useful at a given moment are recruited and integrated into actual behavior. At the heart of the model are regulating structures that restrain information from flowing freely between the different cortical areas involved, releasing it instead in a controlled fashion able to produce the appropriate response. The dynamics of the network, simulated on a computer, enables it to pass simple cognitive tests while reproducing data gathered on primates carrying out these same tasks. This suggests that the model might constitute an appropriate framework for studying the neural basis of more general behavior.
Published: 2006
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161. Identification of large-scale networks in the brain using fMRI

Author: Julien Doyon, Mélanie Pélégrini-Issac, Saâd Jbabdi, Habib Benali, Vincent Perlbarg, Jean-Luc Anton, Pierre Bellec, Laboratoire d'Imagerie Fonctionnelle (LIF), Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR14-IFR49-Institut National de la Santé et de la Recherche Médicale (INSERM), Radiologie et imagerie médicale, Assistance Publique - Hôpitaux de Marseille (APHM)- Hôpital de la Timone [CHU - APHM] (TIMONE), Department of Psychology, University of Montreal, and Saidi, Vanessa
Subjects: Male, Computer science, Statistics as Topic, MESH: Nerve N, computer.software_genre, MESH: Magnetic Resonance Imaging, Mental Processes, 0302 clinical medicine, Image Processing, Computer-Assisted, MESH: Mathematical Computing, Mathematical Computing, Default mode network, MESH: Brain Mapping, MESH: Mental Processes, Cerebral Cortex, Brain Mapping, 0303 health sciences, Fourier Analysis, medicine.diagnostic_test, Artificial neural network, Functional connectivity, Cognition, Magnetic Resonance Imaging, MESH: Image Processing, Computer-Assisted, Neurology, [SDV.IB]Life Sciences [q-bio]/Bioengineering, Data mining, Adult, Cognitive Neuroscience, Image processing, MESH: Imaging, Three-Dimensional, Serial Learning, Stimulus (physiology), 03 medical and health sciences, Imaging, Three-Dimensional, MESH: Computer Simulation, Orientation, Reaction Time, medicine, Humans, Computer Simulation, Dominance, Cerebral, 030304 developmental biology, [SDV.IB] Life Sciences [q-bio]/Bioengineering, MESH: Humans, business.industry, Reproducibility of Results, Pattern recognition, MESH: Adult, MESH: Dominance, Cerebral, MESH: Male, MESH: Cerebral Cortex, Neural Networks, Computer, Artificial intelligence, Nerve Net, business, Functional magnetic resonance imaging, computer, Psychomotor Performance, Software, 030217 neurology & neurosurgery, MESH: Fourier Analysis
Abstract: Cognition is thought to result from interactions within large-scale networks of brain regions. Here, we propose a method to identify these large-scale networks using functional magnetic resonance imaging (fMRI). Regions belonging to such networks are defined as sets of strongly interacting regions, each of which showing a homogeneous temporal activity. Our method of large-scale network identification (LSNI) proceeds by first detecting functionally homogeneous regions. The networks of functional interconnections are then found by comparing the correlations among these regions against a model of the correlations in the noise. To test the LSNI method, we first evaluated its specificity and sensitivity on synthetic data sets. Then, the method was applied to four real data sets with a block-designed motor task. The LSNI method correctly recovered the regions whose temporal activity was locked to the stimulus. In addition, it detected two other main networks highly reproducible across subjects, whose activity was dominated by slow fluctuations (0-0.1 Hz). One was located in medial and dorsal regions, and mostly overlapped the "default" network of the brain at rest [Greicius, M.D., Krasnow, B., Reiss, A.L., Menon, V., 2003. Functional connectivity in the resting brain: a network analysis of the default mode hypothesis. Proceedings of the National Academy of Sciences of the U.S.A. 100, 253-258]; the other was composed of lateral frontal and posterior parietal regions. The LSNI method we propose allows to detect in an exploratory and systematic way all the regions and large-scale networks activated in the working brain.
Published: 2006
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162. Pretargeting for the implantation of stimulation electrodes into the subthalamic nucleus: a comparative study of magnetic resonance imaging and ventriculography

Author: Alim-Louis Benabid, Jean-Francois LeBas, Sorin Breit, Jo¨rg Schulz, Pierre Pollak, Adnan Koudsie, Abdelhamid Benazzouz, Neurosciences précliniques, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Service central de radiologie et d'imagerie médicale, CHU Grenoble-Hôpital Michallon, Département de neurologie, Université Joseph Fourier - Grenoble 1 (UJF)-CHU Grenoble, Issartel, Jean-Paul, Service de médecine interne [CHU Saint-Antoine], Université Pierre et Marie Curie - Paris 6 (UPMC)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Saint-Antoine [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU), Département de neurochirurgie, Deutscher Wetterdienst [Offenbach] (DWD), Physiologie et physiopathologie de la signalisation cellulaire (PPSC), Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-CHU Bordeaux [Bordeaux]-Centre National de la Recherche Scientifique (CNRS), Collaboration, Service de médecine interne [Saint-Antoine], Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-CHU Bordeaux [Bordeaux]-Centre National de la Recherche Scientifique (CNRS), and Serduc, Raphael
Subjects: medicine.medical_treatment, Deep Brain Stimulation, Stimulation, 030218 nuclear medicine & medical imaging, MESH: Magnetic Resonance Imaging, Stereotaxic Techniques, 0302 clinical medicine, Posterior commissure, Microstimulation, Medicine, MESH: Brain Mapping, Pretargeting, Brain Mapping, medicine.diagnostic_test, MESH: Cerebral Ventriculography, Parkinson Disease, MESH: Follow-Up Studies, Commissure, Magnetic Resonance Imaging, Electrodes, Implanted, Subthalamic nucleus, Electrode, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Tomography, MESH: Tomography, X-Ray Computed, Deep brain stimulation, MESH: Stereotaxic Techniques, Anterior commissure, 03 medical and health sciences, Subthalamic Nucleus, [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology, Humans, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, [SDV.NEU] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Cerebral Ventriculography, MESH: Subthalamic Nucleus, MESH: Humans, business.industry, Magnetic resonance imaging, ddc:616.8, Surgery, MESH: Electrodes, Implanted, Neurology (clinical), MESH: Deep Brain Stimulation, Nuclear medicine, business, Tomography, X-Ray Computed, Neuroscience, 030217 neurology & neurosurgery, MESH: Parkinson Disease, Follow-Up Studies
Abstract: OBJECTIVE: The optimal imaging modality for preoperative targeting of the subthalamic nucleus (STN) for high-frequency stimulation is controversially discussed. Commonly used methods were stereotactic magnetic resonance imaging (MRI), stereotactic ventriculography, and fusion between MRI and stereotactic computer tomography. All of these techniques not only have their own advantages but also specific limitations and drawbacks. The purpose of this study was to evaluate the accuracy of the preoperative MRI targeting as compared with ventriculography in terms of both the STN target as well as the internal landmarks. METHODS: Thirty patients with Parkinson's disease who underwent bilateral surgery for STN-high-frequency stimulation received both stereotactic ventriculography and stereotactic MRI. The theoretical target was determined by each of these two imaging modalities. The final electrode placement was performed after extensive electrophysiological evaluation using microrecording and microstimulation. The real target was assumed to be given by the electrode contact with the best clinical result assessed by the United Parkinson's Disease Rating Scale in the postoperative follow-up. In addition, the coordinates of the two landmarks, anterior commissure and posterior commissure, were determined using both imaging methods. RESULTS: The mean targeting error was 4.1 ± 1.7 mm (mean ± standard deviation) for MRI and 2.4 ± 1.1 mm for ventriculography (P < 0.0001). The mean target mismatch between the two imaging methods was 2.9 ± 1.2 mm. The length of the anterior commissure-posterior commissure distance differed significantly (P < 0.0001) between MRI (27.6 ± 1.6 mm) and ventriculography (25.0 ± 1.3 mm). The mismatch was mainly induced by an anterior diplacement of the anterior commissure by 1.9 ± 2.2 mm (P < 0.0001) in MRI determination, as compared with ventriculography. CONCLUSION: Our findings show that the indirect targeting of the STN using coordinates based on radiological landmarks is more accurate than the direct targeting using anatomic visualization of the target structure. Regardless of the imaging procedure, electrophysiological mapping is required for optimal electrode placement, although in 20% of cases, the target determined by MRI falls out of the radius explored by electrophysiology.
Published: 2006
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163. Functional role of the basal ganglia in the planning and execution of actions

Author: Michael Petrides, Oury Monchi, Julien Doyon, Antonio P. Strafella, Keith J. Worsley, Unité de Neuroimagerie Fonctionnelle [Montréal] (UNF-CRIUGM), Université de Montréal (UdeM)-Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal (CRIUGM), Department of Radiology, University of Montreal, Montreal Neurological Institute and Hospital, McGill University = Université McGill [Montréal, Canada], Department of Psychology, and Saidi, Vanessa
Subjects: Adult, Male, Adolescent, Caudate nucleus, MESH: Mental Recall, Striatum, Neuropsychological Tests, Basal Ganglia, MESH: Magnetic Resonance Imaging, MESH: Basal Ganglia, Basal ganglia, Image Processing, Computer-Assisted, medicine, Humans, Attention, MESH: Caudate Nucleus, Problem Solving, MESH: Brain Mapping, MESH: Adolescent, [SDV.IB] Life Sciences [q-bio]/Bioengineering, Brain Mapping, MESH: Attention, MESH: Humans, medicine.diagnostic_test, Putamen, MESH: Adult, MESH: Neuropsychological Tests, Executive functions, Magnetic Resonance Imaging, MESH: Image Processing, Computer-Assisted, MESH: Male, Oxygen, Subthalamic nucleus, MESH: Photic Stimulation, Neurology, Mental Recall, Female, [SDV.IB]Life Sciences [q-bio]/Bioengineering, Neurology (clinical), Caudate Nucleus, Psychology, Functional magnetic resonance imaging, Motor learning, Neuroscience, MESH: Female, Photic Stimulation, MESH: Oxygen, MESH: Problem Solving
Abstract: Objective: Recent studies of functional brain imaging have shown the involvement of the basal ganglia in executive processes such as planning and set-shifting. However, the specific contributions of the striatum in those processes remain unknown. This study aimed to test the hypothesis that the caudate nucleus is primarily involved in the preparation of a novel action and not in set-shifting per se. Methods: In the present event-related functional magnetic resonance imaging (fMRI) study, a new task was developed that permitted, for the first time, to distinguish between shifts in classification when the rule is implicitly given by the task from shifts that require cognitive comparison and planning. Results: Significantly increased activity in the caudate nucleus and the putamen was observed only in conditions in which cognitive planning was required to perform a set-shift, whereas significant activation was seen in the subthalamic nucleus (another region of the basal ganglia) in all shifting conditions whether or not planning was required. Interpretation: We suggest that the caudate nucleus and the putamen are particularly important, respectively, in the planning and the execution of a self-generated novel action, whereas the subthalamic nucleus may be required when a new motor program is solicited independently of the choice of strategy. Ann Neurol 2006;59:257–264 Abnormalities of the basal ganglia (BG) have been described in many neurological disorders such as Parkinson’s disease, and thus it is important to gain a greater understanding of the functional role of the different nuclei of the BG in the healthy brain in order to reveal the neural origins of the cognitive and motor deficits observed in those disorders. Traditionally thought to be associated with the control of movement 1–3 and motor learning, 4,5 BG has been shown by neuropsychological studies in patients with Parkinson’s and Huntington’s disease to contribute to a variety of executive functions, including planning and set-shifting (ie, the ability to alter our mode of response in the face of changing circumstances). 6– 9 Among the different BG nuclei, the caudate nucleus has been shown to play a greater role in executive processes, 10 –14 whereas other structures such as the putamen and subthalamic nucleus have traditionally been associated with more motor-related activities. However, there is evidence that the role of the putamen may not be directly linked to the movement itself, but rather to the condition under which it is made, 15 whereas the subthalamic nucleus may exert a specific influence on the BG output related to the control of movement. 3,16,17 Hence, whereas the evidence accumulated to date suggests that the various nuclei of the BG may have different functional roles, their distinct contribution to the planning and execution of action remains unknown.
Published: 2006
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164. Children recruit distinct neural systems for implicit emotional face processing

Author: Margot J. Taylor, Nancy J. Lobaugh, Erin Gibson, Marlot, Catherine, Centre de recherche cerveau et cognition (CERCO), Institut des sciences du cerveau de Toulouse. (ISCT), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Male, MESH: Facial Expression, Emotions, Functional Laterality, Developmental psychology, MESH: Magnetic Resonance Imaging, Gyrus, MESH: Child, Neural Pathways, Image Processing, Computer-Assisted, Child, Evoked Potentials, MESH: Brain Mapping, media_common, Brain Mapping, medicine.diagnostic_test, General Neuroscience, Brain, Cognition, MESH: Comparative Study, MESH: Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Sadness, Facial Expression, MESH: Evoked Potentials, medicine.anatomical_structure, Pattern Recognition, Visual, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Female, Psychology, Parahippocampal gyrus, MESH: Oxygen, psychological phenomena and processes, media_common.quotation_subject, MESH: Pattern Recognition, Visual, Amygdala, behavioral disciplines and activities, MESH: Laterality, MESH: Brain, medicine, Reaction Time, Humans, [SDV.NEU] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], MESH: Emotions, MESH: Humans, MESH: Neural Pathways, MESH: Reacti, Disgust, MESH: Male, Oxygen, nervous system, Functional magnetic resonance imaging, Insula, MESH: Female
Abstract: The ability to properly distinguish facial emotions has a protracted development, not maturing until well into adolescence. Emotional faces activate emotion-specific neural networks in adults; whether these networks are operational in children is not known. Using an implicit face-processing task in 10-year-old children, we determined that the emotions of fear, disgust and sadness recruited distinct neural systems. These systems included a number of regions typically associated with processing emotions in adults, namely the amygdala and parahippocampal gyrus, insula and cingulate gyrus, as well as the fusiform and superior temporal gyri. Thus, in spite of immature behavioral responses to emotional faces in explicit tasks, neural networks for emotion-specific processing are present in young children.
Published: 2006

165. Intracerebral dynamics of saccade generation in the human frontal eye field and supplementary eye field

Author: Philippe Kahane, Jean-Philippe Lachaux, Dominique Hoffmann, Alain Berthoz, Lorella Minotti, Deransart, Colin, Biologie et pathologie digestive, Institut Louis Bugnard-Institut National de la Santé et de la Recherche Médicale (INSERM), Neurosciences cognitives et imagerie cérébrale (NCIC), Centre National de la Recherche Scientifique (CNRS), Neurosciences précliniques, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Département de neurologie, Université Joseph Fourier - Grenoble 1 (UJF)-CHU Grenoble, Laboratoire de Physiologie de la Perception et de l'Action (LPPA), Collège de France (CdF (institution))-Centre National de la Recherche Scientifique (CNRS), and Collaboration
Subjects: Supplementary eye field, genetic structures, MESH: Frontal Lobe, Electroencephalography, MESH: Signal Processing, Computer-Assisted, 0302 clinical medicine, Oculomotor Nerve, Neural Pathways, Evoked Potentials, MESH: Brain Mapping, Cerebral Cortex, Brain Mapping, 0303 health sciences, Fourier Analysis, medicine.diagnostic_test, MESH: Electric Stimulation, Signal Processing, Computer-Assisted, Time resolution, Electrodes, Implanted, Frontal Lobe, MESH: Evoked Potentials, Neurology, Saccade, Visual Perception, MESH: Saccades, Psychology, Cognitive Neuroscience, MESH: Orientation, 03 medical and health sciences, Orientation, MESH: Electroencephalography, Reaction Time, Saccades, medicine, Humans, Dominance, Cerebral, 030304 developmental biology, MESH: Oculomotor Nerve, MESH: Humans, MESH: Visual Perception, MESH: Neural Pathways, Eye movement, MESH: Dominance, Cerebral, Electric Stimulation, Saccadic masking, MESH: Cerebral Cortex, MESH: Reaction Time, Functional imaging, MESH: Epilepsies, Partial, Temporal resolution, MESH: Electrodes, Implanted, Epilepsies, Partial, Neuroscience, 030217 neurology & neurosurgery, MESH: Fourier Analysis
Abstract: International audience; Recent functional imaging and electrical stimulation studies have localized in humans two frontal regions critical for the production of saccadic and anti-saccadic eye movements: the frontal and supplementary eye fields (FEF and SEF, respectively). We investigated the time course of their activations during the generation of pro- and anti-saccades from direct intracranial EEG recordings of three human epileptic patients. We found the preparation and the production of the saccades to be coincident with focal and transient increases of EEG power above 60 Hz. Those were produced in very specific brain sites distributed in the FEF and the SEF (as identified by previous human studies at a coarser time resolution). Furthermore, the spatio-temporal resolution of those recordings turned out to be sufficient to discriminate anatomically between several types of neural responses, determined either by the visual or by the motor components of the saccade tasks, and within this second category of responses, between some associated with the preparation of the saccades and others associated with their execution. Altogether, this study provides the first evidence of high-frequency neural responses in the generation of saccades in humans, and provides a firm basis for other studies detailing further the functional organization of the human oculomotor system at this level of spatial and temporal resolution.
Published: 2006
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166. Rapamycin inhibits growth and survival of D-816-V-mutated c-kit mast cells

Author: Yves Lepelletier, Olivier Lortholary, Guy Laurent, Martine Humbert, Olivier Hermine, Jean Pierre Zappulla, Antoine Ribadeau-Dumas, Marion Gabillot-Carré, Nadine Ben Hamouda, Paulo de Sepuvelda, Christian Recher, Emmanuel Morelon, Christine Bodemer, François Machavoine, Cédric Baude, Aurélie Hermant, Patrice Dubreuil, Jacques Vargaftig, Michel Arock, Sébastien Letard, Michel Dy, Roland S. Liblau, Ying Yang, Cytokines, hématopoïèse et réponse immune (CHRI), Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre de Physiopathologie Toulouse Purpan ex IFR 30 et IFR 150 (CPTP), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'immunologie, Hôpital de Rangueil, CHU Toulouse [Toulouse]-CHU Toulouse [Toulouse], Cancérologie, Université de la Méditerranée - Aix-Marseille 2-Institut National de la Santé et de la Recherche Médicale (INSERM), Service de dermatologie [CHU Necker], Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-CHU Necker - Enfants Malades [AP-HP], Centre d'infectiologie Necker-Pasteur [CHU Necker], CHU Necker - Enfants Malades [AP-HP], Laboratoire de Biologie et de Pharmacologie Appliquée (LBPA), École normale supérieure - Cachan (ENS Cachan)-Centre National de la Recherche Scientifique (CNRS), Service d'immuno-hématologie pédiatrique [CHU Necker], Centre de Physiopathologie Toulouse Purpan (CPTP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Cancérologie (Inserm U599/IPC), Université de la Méditerranée - Aix-Marseille 2-Institut Paoli-Calmettes, Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Institut National de la Santé et de la Recherche Médicale (INSERM), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Necker - Enfants Malades [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Institut Pasteur [Paris]-CHU Necker - Enfants Malades [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Département Immunologie [CHU Toulouse], Institut Fédératif de Biologie (IFB), Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Pôle Biologie [CHU Toulouse], Centre Hospitalier Universitaire de Toulouse (CHU Toulouse), Institut Pasteur [Paris] (IP)-CHU Necker - Enfants Malades [AP-HP], Slama, Catherine, Cytokines, hématopoïèse et réponse immune ( CHRI ), Université Paris Descartes - Paris 5 ( UPD5 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Centre de Physiopathologie Toulouse Purpan (ex IFR 30 et IFR 150), Université Toulouse III - Paul Sabatier ( UPS ), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-IFR30-IFR150-Institut National de la Santé et de la Recherche Médicale ( INSERM ), Université de la Méditerranée - Aix-Marseille 2-Institut National de la Santé et de la Recherche Médicale ( INSERM ), Assistance publique - Hôpitaux de Paris (AP-HP)-CHU Necker - Enfants Malades [AP-HP], Laboratoire de Biologie et de Pharmacologie Appliquée ( LBPA ), École normale supérieure - Cachan ( ENS Cachan ) -Centre National de la Recherche Scientifique ( CNRS ), and Université Paris Descartes - Paris 5 (UPD5) - Institut National de la Santé et de la Recherche Médicale (INSERM) - Centre National de la Recherche Scientifique (CNRS)
Subjects: MESH: Signal Transduction, MESH : Brain Mapping, Apoptosis, medicine.disease_cause, Biochemistry, MESH: Magnetic Resonance Imaging, MESH : Auditory Perception, Mice, 0302 clinical medicine, MESH : Tumor Cells, Cultured, MESH : Neural Pathways, MESH : Cell Proliferation, Tumor Cells, Cultured, [ SDV.IMM ] Life Sciences [q-bio]/Immunology, MESH: Animals, Mast Cells, Systemic mastocytosis, MESH: Mastocytosis, Systemic, MESH: Brain Mapping, MESH : Cell Survival, 0303 health sciences, Mutation, MESH: Music, TOR Serine-Threonine Kinases, MESH : Music, MESH : Mastocytosis, Systemic, MESH: Mast Cells, Hematology, MESH : Mice, Transgenic, MESH: Positron-Emission Tomography, 3. Good health, MESH: Proto-Oncogene Proteins c-kit, Proto-Oncogene Proteins c-kit, MESH: Cell Survival, Phosphorylation, [SDV.IMM]Life Sciences [q-bio]/Immunology, MESH : Mast Cells, MESH : Pharmacogenetics, Tyrosine kinase, MESH : Time Factors, medicine.drug, Signal Transduction, Cell Survival, MESH: Mice, Transgenic, Immunology, Mutation, Missense, MESH: Acoustic Stimulation, MESH: Pharmacogenetics, Mice, Transgenic, MESH : Protein Kinases, Biology, MESH : Proto-Oncogene Proteins c-kit, MESH : Emotions, 03 medical and health sciences, MESH: Auditory Perception, MESH: Brain, Mastocytosis, Systemic, MESH: Models, Neurological, MESH : Magnetic Resonance Imaging, MESH: Cell Proliferation, MESH : Mice, medicine, MESH : Models, Neurological, Animals, Humans, MESH: Tumor Cells, Cultured, MESH: Mice, MESH: Protein Kinases, PI3K/AKT/mTOR pathway, 030304 developmental biology, Cell Proliferation, MESH: Emotions, MESH : Signal Transduction, Sirolimus, MESH: Mutation, Missense, MESH: Humans, MESH : Sirolimus, MESH: Apoptosis, MESH: Neural Pathways, MESH : Humans, RPTOR, MESH: Time Factors, MESH : Positron-Emission Tomography, Cell Biology, MESH : Acoustic Stimulation, medicine.disease, MESH : Brain, Pharmacogenetics, Cancer research, MESH : Animals, MESH: Sirolimus, Protein Kinases, MESH : Apoptosis, MESH : Mutation, Missense, 030215 immunology
Abstract: International audience; Two classes of oncogenic mutations of the c-kit tyrosine kinase have been described: the juxtamembrane domain V560G mutation, which is preferentially found in gastrointestinal stromal tumors (GISTs), and the kinase domain D816V mutation, which is highly representative of systemic mastocytosis (SM). Here we show that both mutations constitutively activate the mammalian target of rapamycin (mTOR) signaling pathway. Surprisingly, the mTOR inhibitor rapamycin induces only apoptosis in HMC-1 cells bearing the D816V but not the V560G mutation. In support of this unexpected selectivity, rapamycin inhibits the phosphorylation of 4E-BP1, a downstream substrate of the mTOR pathway, but only in D816V HMC-1 cells. Importantly, D816V mast cells isolated from SM patients or from transgenic mice are sensitive to rapamycin whereas normal human or mouse mast cells are not. Thus, rapamycin inhibition appears specific to the D816V mutation. At present there is no effective cure for SM patients with the D816V mutation. The data presented here provide a rationale to test whether rapamycin could be a possible treatment for SM and other hematologic malignancies with the D816V mutation.
Published: 2006
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167. Syntax production in bilinguals

Author: Christophe Pallier, Narly Golestani, Stanislas Dehaene, Sébastien Mériaux, Denis Le Bihan, F-Xavier Alario, Laboratoire de psychologie cognitive (LPC), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Service Hospitalier Frédéric Joliot (SHFJ), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Service NEUROSPIN (NEUROSPIN), IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Human Brain Research Center [Kyoto] (HBRC), Kyoto University [Kyoto], National Institutes of Health [Bethesda] (NIH), Chaire Psychologie cognitive expérimentale, Collège de France (CdF (institution)), Neuroimagerie cognitive (LCogn), Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Santé et de la Recherche Médicale (INSERM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Kyoto University, and Collège de France - Chaire Psychologie cognitive expérimentale
Subjects: Male, Speech production, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Multilingualism, MESH: Frontal Lobe, Psycholinguistics, MESH: Semantics, MESH: Magnetic Resonance Imaging, Behavioral Neuroscience, 0302 clinical medicine, Image Processing, Computer-Assisted, MESH: Brain Mapping, Brain Mapping, Supplementary motor area, 05 social sciences, Motor Cortex, Language acquisition, Magnetic Resonance Imaging, MESH: Image Processing, Computer-Assisted, Linguistics, Frontal Lobe, Semantics, medicine.anatomical_structure, Female, Psychology, Sentence, MESH: Oxygen, Adult, Cognitive Neuroscience, MESH: Multilingualism, Posterior parietal cortex, Experimental and Cognitive Psychology, MESH: Imaging, Three-Dimensional, MESH: Reading, MESH: Motor Cortex, 050105 experimental psychology, MESH: Psycholinguistics, 03 medical and health sciences, Imaging, Three-Dimensional, medicine, Humans, 0501 psychology and cognitive sciences, Dominance, Cerebral, MESH: Verbal Behavior, MESH: Humans, Language production, Verbal Behavior, MESH: Adult, MESH: Dominance, Cerebral, Syntax, MESH: Male, Oxygen, Reading, MESH: Female, 030217 neurology & neurosurgery
Abstract: International audience; We used fMRI to examine the functional correlates of syntactical processing in the first (L1) and second (L2) languages of non-proficient, late bilinguals. Subjects either covertly read words or produced sentences from them. Syntactical production during sentence production activated regions including left inferior frontal (LIFG) gyrus and the supplementary motor area in both languages. Analyses performed on the LIFG activation identified on a subject-by-subject basis revealed greater activation in L2 compared to L1 during sentence production and during word reading, consistent with previous work suggesting that greater cognitive effort may be subserved by less well-tuned neural representations that require greater neuronal activity. Remarkably, there was a greater separation in the LIFG activations in L1 versus L2 in less compared to more proficient bilinguals during syntax production, suggesting a functional reorganisation of regions involved in syntactical production as a function of syntactical proficiency.
Published: 2006
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168. New concepts in surgery of WHO grade II gliomas: functional brain mapping, connectionism and plasticity--a review

Author: Hugues Duffau, Saidi, Vanessa, Laboratoire d'Imagerie Fonctionnelle (LIF), and Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR14-IFR49-Institut National de la Santé et de la Recherche Médicale (INSERM)
Subjects: Diagnostic Imaging, Cancer Research, medicine.medical_specialty, Neurology, Eloquent Brain Areas, MESH: Monitoring, Intraoperative, World Health Organization, Brain mapping, Neurosurgical Procedures, MESH: World Health Organization, White matter, MESH: Glioma, 03 medical and health sciences, 0302 clinical medicine, Glioma, Monitoring, Intraoperative, Neuroplasticity, Neural Pathways, medicine, Humans, Neuropsychological assessment, MESH: Neuronal Plasticity, MESH: Brain Mapping, [SDV.IB] Life Sciences [q-bio]/Bioengineering, Brain Mapping, Neuronal Plasticity, MESH: Humans, medicine.diagnostic_test, business.industry, Brain Neoplasms, MESH: Diagnostic Imaging, MESH: Neural Pathways, MESH: Neurosurgical Procedures, Perioperative, medicine.disease, 3. Good health, Surgery, MESH: Cognition Disorders, medicine.anatomical_structure, Oncology, 030220 oncology & carcinogenesis, MESH: Brain Neoplasms, [SDV.IB]Life Sciences [q-bio]/Bioengineering, Neurology (clinical), business, Cognition Disorders, 030217 neurology & neurosurgery
Abstract: Despite a recent literature supporting the impact of surgery on the natural history of low-grade glioma (LGG), the indications of resection still remain a matter of debate, especially because of the frequent location of these tumors within eloquent brain areas – thus with a risk to induce a permanent postoperative deficit. Therefore, since the antagonist nature of this surgery is to perform the most extensive glioma removal possible, while preserving the function and the quality of life, new concepts were recently applied to LGG resection in order to optimize the␣benefit/risk ratio of the surgery. First, due to the development of functional mapping methods, namely perioperative neurofunctional imaging and intrasurgical direct electrical stimulation, the study of cortical functional organization is currently possible for each patient – in addition to an extensive neuropsychological assessment. Such knowledge is essential because of the inter-individual anatomo-functional variability, increased in tumors due to cerebral plasticity phenomena. Thus, brain mapping enables to envision and perform a resection according to individual functional boundaries. Second, since LGG invades not only cortical but also subcortical structures, and shows an infiltrative progression along the white matter tracts, new techniques of anatomical tracking and functional mapping of the subcortical white matter pathways were also used with the goal to study the individual effective connectivity – which needs imperatively to be preserved during the resection. Third, the better understanding of brain plasticity mechanisms, induced both by the slow-growing LGG and by the surgery itself, were equally studied in each patient and applied to the surgical strategy by incorporating individual dynamic potential of reorganization into the operative planning. The integration of these new concepts of individual functional mapping, connectivity and plastic potential to the surgery of LGG has allowed an extent of surgical indications, an optimization of the quality of resection (neuro-oncological benefit), and a minimization of the risk of sequelae (benefit on the quality of life). In addition, such a strategy has also fundamental applications, since it represents a new door to the connectionism and cerebral plasticity.
Published: 2006
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169. In vivo profiling of focal cortical dysplasia on high-resolution MRI with computational models

Author: Neda Bernasconi, Andrea Bernasconi, Olivier Colliot, V. Naessens, Samson B. Antel, McConnell Brain Imaging Centre (MNI), Montreal Neurological Institute and Hospital, McGill University = Université McGill [Montréal, Canada]-McGill University = Université McGill [Montréal, Canada], and Colliot, Olivier
Subjects: Male, Pathology, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, [SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology, [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, MESH: Videotape Recording, High resolution, 030218 nuclear medicine & medical imaging, MESH: Magnetic Resonance Imaging, [INFO.INFO-CV] Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], 0302 clinical medicine, MESH: Mathematical Computing, Mathematical Computing, MESH: Brain Mapping, Cerebral Cortex, Brain Mapping, medicine.diagnostic_test, Electroencephalography, Magnetic Resonance Imaging, medicine.anatomical_structure, [INFO.INFO-TI] Computer Science [cs]/Image Processing [eess.IV], Neurology, MESH: Epilepsy, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], Female, medicine.symptom, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, Adult, MESH: Preoperative Care, medicine.medical_specialty, Models, Neurological, MESH: Imaging, Three-Dimensional, Nervous System Malformations, MESH: Nervous System Malformations, Central nervous system disease, Lesion, White matter, 03 medical and health sciences, Imaging, Three-Dimensional, In vivo, MESH: Models, Neurological, Image Interpretation, Computer-Assisted, Preoperative Care, MESH: Electroencephalography, medicine, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Humans, [SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processing, Epilepsy, MESH: Humans, business.industry, [SDV.NEU.NB] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology, Videotape Recording, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], Magnetic resonance imaging, MESH: Adult, Cortical dysplasia, medicine.disease, MESH: Male, MESH: Cerebral Cortex, [SDV.IB.IMA] Life Sciences [q-bio]/Bioengineering/Imaging, Dysplasia, Neurology (clinical), business, Nuclear medicine, MESH: Female, MESH: Image Interpretation, Computer-Assisted, 030217 neurology & neurosurgery
Abstract: International audience; On MRI, focal cortical dysplasia (FCD) is characterized by a combination of increased cortical thickness, hyperintense signal within the dysplastic lesion, and blurred transition between gray and white matter (GM-WM). The visual identification of these abnormal characteristics may be difficult, and it is unclear to what degree these features occur among different FCD lesions. Our purpose was to investigate the pattern of occurrence of abnormal MRI characteristics in FCD by using a set of computational models and to generate quantitative lesion profiling. A set of voxel-wise operators was applied to high-resolution 3D T1-weighted MRI in 23 patients with histologically proven FCD and 39 healthy controls, creating maps of GM thickness, maps of relative intensity highlighting areas with hyperintense signal, and maps of gradient magnitude modeling the GM-WM transition. All FCD lesions were segmented manually on the T1-weighted MRI. FCD volumes ranged from 734 mm3 to 80,726 mm3 (mean, 8,629 mm3 +/- 16,238). The manually segmented FCD lesions were used to estimate features in the lesional area and to determine possible local variations of each feature by means of a histogram. In 78% of the patients, FCD lesions were characterized by simultaneous GM thickening, hyperintense signal, and blurring of the GM-WM transition. Moreover, in all patients, the FCD lesion had at least two of these three characteristics. The three features occurred regardless of the lesion volume, and they characterized not only large FCD lesions, but also subtle ones that had been overlooked by conventional radiologic inspection before surgery.
Published: 2006

170. What is the relationship between phonological short-term memory and speech processing?

Author: Sophie K. Scott, Charlotte Jacquemot, Département d'Etudes Cognitives - ENS Paris (DEC), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Institut Mondor de Recherche Biomédicale (IMRB), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Institute of Cognitive Neuroscience, University College of London [London] (UCL), Laboratoire de sciences cognitives et psycholinguistique (LSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS), Institute of Cognitive Neuroscience (ICN), and École normale supérieure - Paris (ENS-PSL)
Subjects: Speech production, MESH: Comprehension, Sign Language, 0302 clinical medicine, MESH: Serial Learning, Attention, MESH: Brain Mapping, Language, Cerebral Cortex, Brain Mapping, MESH: Speech, 05 social sciences, [SDV.NEU.SC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Cognitive Sciences, Cognition, Phonology, Verbal Learning, Language acquisition, Neuropsychology and Physiological Psychology, Memory, Short-Term, MESH: Language, [SCCO.PSYC]Cognitive science/Psychology, Speech Perception, Psychology, Comprehension, Cognitive psychology, Speech perception, Cognitive Neuroscience, MESH: Phonetics, Short-term memory, Experimental and Cognitive Psychology, Serial Learning, 050105 experimental psychology, MESH: Memory, Short-Term, 03 medical and health sciences, Phonetics, Humans, Speech, 0501 psychology and cognitive sciences, Dominance, Cerebral, MESH: Sign Language, MESH: Attention, MESH: Humans, Working memory, [SCCO.NEUR]Cognitive science/Neuroscience, MESH: Speech Perception, MESH: Dominance, Cerebral, [SCCO.LING]Cognitive science/Linguistics, Speech processing, MESH: Verbal Learning, MESH: Cerebral Cortex, MESH: Nerve Net, Practice, Psychological, Nerve Net, 030217 neurology & neurosurgery, MESH: Practice (Psychology)
Abstract: International audience; Traditionally, models of speech comprehension and production do not depend on concepts and processes from the phonological short-term memory (pSTM) literature. Likewise, in working memory research, pSTM is considered to be a language-independent system that facilitates language acquisition rather than speech processing per se. We discuss couplings between pSTM, speech perception and speech production, and we propose that pSTM arises from the cycling of information between two phonological buffers, one involved in speech perception and one in speech production. We discuss the specific role of these processes in speech processing, and argue that models of speech perception and production, and our understanding of their neural bases, will benefit from incorporating them.
Published: 2006
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171. Diffusion tensor imaging in medial temporal lobe epilepsy with hippocampal sclerosis

Author: Stéphane Lehéricy, Sophie Dupont, Michel Baulac, Claude Adam, Jacques Chiras, Didier Dormont, Lionel Thivard, Alexandre Krainik, Cortex et Epilepsie [Paris], CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC), Service de Neurologie [CHU Pitié-Salpêtrière], IFR70-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Service de Neuroradiologie [CHU Pitié-Salpêtrière], Center for Magnetic Resonance Research [Minneapolis] (CMRR), University of Minnesota Medical School, University of Minnesota System-University of Minnesota System, Service d'Imagerie par Résonance Magnétique (IRM), CHU Grenoble, Neuroimagerie Fonctionnelle et Metabolique, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Neurosciences cognitives et imagerie cérébrale (NCIC), Centre National de la Recherche Scientifique (CNRS), Collaboration, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Dojat, Michel, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC), Service de neurologie 1 [CHU Pitié-Salpétrière], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU), and Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)
Subjects: Adult, Male, MESH: Hippocampus, Cognitive Neuroscience, MESH: Age of Onset, Hippocampus, MESH: Diffusion Magnetic Resonance Imaging, Statistical parametric mapping, Brain mapping, Seizures, Febrile, 030218 nuclear medicine & medical imaging, Temporal lobe, 03 medical and health sciences, Epilepsy, 0302 clinical medicine, Image Processing, Computer-Assisted, medicine, Humans, Ictal, Age of Onset, MESH: Brain Mapping, Brain Mapping, Hippocampal sclerosis, Sclerosis, MESH: Middle Aged, MESH: Humans, MESH: Adult, Middle Aged, medicine.disease, MESH: Image Processing, Computer-Assisted, MESH: Male, MESH: Seizures, Febrile, Diffusion Magnetic Resonance Imaging, Epilepsy, Temporal Lobe, Neurology, MESH: Epilepsy, Temporal Lobe, MESH: Anisotropy, Anisotropy, Female, Epilepsy, Tonic-Clonic, MESH: Sclerosis, Psychology, Neuroscience, MESH: Female, 030217 neurology & neurosurgery, MESH: Epilepsy, Tonic-Clonic, Diffusion MRI
Abstract: International audience; Interictal diffusion imaging studies in patients with medial temporal lobe epilepsy (MTLE) accompanied by hippocampal sclerosis (HS) have shown an increased diffusivity in the epileptogenic hippocampus. In this study, we wanted to explore the whole brain in order to determine if MTLE could have an impact on the organization and the architecture of a large cerebral network and to identify clinical factors that could mediate diffusion abnormalities. Diffusion tensor imaging (DTI) and statistical parametric mapping of the entire brain were performed in 35 well-defined MTLE patients and in 36 healthy volunteers. SPM analyses identified three abnormal areas: an increased diffusivity was detected in the epileptic hippocampus and the ipsilateral temporal structures associated with a decreased anisotropy along the temporal lobe, a decreased diffusivity was found in the contralateral non-sclerotic hippocampus, the amygdala, and the temporal pole, and finally, a decreased anisotropy was noted ipsilaterally in posterior extratemporal regions. Duration of epilepsy, age at onset, and the frequency of generalized tonic-clonic seizures or partial complex seizures did not correlate with the presence of diffusion abnormalities. Region of interest analysis in the hippocampus/parahippocampus demonstrated a correlation between lower ipsilateral diffusivity values and occurrence of epigastric aura and between higher anisotropy values in both hemispheres and history of febrile seizures. In conclusion, this study showed that diffusion abnormalities are not restricted to the pathologic hippocampus and involve a larger network. This pattern may indirectly reflect the epileptogenic network and may be interpreted as a cause or a consequence of epilepsy.
Published: 2005
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172. Statistical analysis of 168 bilateral subthalamic nucleus implantations by means of the probabilistic functional atlas

Author: Alim-Louis Benabid, Pierre Pollak, Wieslaw L. Nowinski, Dmitry Belov, Biomedical Imaging Lab, Agency for Science, Technology and Research, Département de neurologie, Université Joseph Fourier - Grenoble 1 (UJF)-CHU Grenoble, Neurosciences précliniques, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Département de neurochirurgie, and Issartel, Jean-Paul
Subjects: medicine.medical_specialty, MESH: Probability, Deep Brain Stimulation, MESH: Depressive Disorder, Major, MESH: Electric Stimulation Therapy, MESH: Stereotaxic Techniques, Probability density function, Standard deviation, Functional Laterality, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, Animal data, MESH: Brain, 0302 clinical medicine, Subthalamic Nucleus, Medicine, Humans, MESH: Functional Laterality, MESH: Brain Mapping, MESH: Numerical Analysis, Computer-Assisted, Probability, MESH: Subthalamic Nucleus, Brain Mapping, MESH: Humans, business.industry, Brain atlas, Probabilistic logic, Pattern recognition, Numerical Analysis, Computer-Assisted, MESH: Neurosurgical Procedures, Surgery, Subthalamic nucleus, Feature (computer vision), Probability distribution, Neurology (clinical), Artificial intelligence, MESH: Deep Brain Stimulation, business, 030217 neurology & neurosurgery
Abstract: OBJECTIVE: Statistical analysis of patients previously operated on may improve our methods of performing subsequent surgical procedures. In this article, we introduce a method for studying the functional properties of cerebral structures from electrophysiological and neuroimaging data by using the probabilistic functional atlas (PFA). The PFA provides a spatial distribution of the clinically most effective contacts normalized to a common space. This distribution is converted into a probability function for a given point in space to be inside an effective contact. The PFA was used to analyze spatial properties of the functional subthalamic nucleus (STN), defined as the spatial volume corresponding to the distribution of effective contacts. These results may potentially be useful in planning subthalamic implantation of electrodes. METHODS: In all, 168 bilateral subthalamic stimulations were examined. An algorithm was developed for converting these data into the PFA. The PFA for the STN (here called “atlas”) was calculated with 0.25-mm3 resolution, and several features characterizing the left and right STN were studied. The analysis was performed with and without lateral compensation against the width of the third ventricle. The key feature introduced here used for analysis of the functional STN is a (probabilistic) functional volume of structure (defined for a given probability as the volume of a region whose every point has a probability equal to or greater than this given probability). RESULTS: The analysis has been performed for two situations: with and without lateral compensation against the width of the third ventricle. Without lateral compensation, the differences between the mean values and standard deviations of their barycenter coordinates for the left and right functional STNs are 0.31 and 0.18 mm, respectively. The left STN and right STN exhibit differences in functional volume size and probability distribution. The entire functional volume is 240 mm3 for the left and 229 mm3 for the right STN. A more prominent difference exists in the region of high probabilities (0.7 or higher), called “hot STN.” The volume of the left hot STN is 5.52 mm3, whereas that of the right is 3.92 mm3. The left hot STN is 1.41 times bigger and 20% more dense than the right hot STN. For a given probability, the corresponding functional volume for the left hot STN is up to 43 times larger than that for the right STN. Practically speaking, lateral compensation does not change these results qualitatively. Quantitatively, differentiation between the left and right STNs is lower. For instance, for a given probability, the corresponding functional volume for the left hot STN is only up to 11 times larger than that for the right one. In either situation (i.e., with and without lateral compensation), the size of the hot STN in relation to the whole STN remains very small (1–2%). In addition, statistical analysis shows that in either situation, the means of the left and right functional STNs are significantly different. CONCLUSION: PFA-based planning may be superior to the current practice of using anatomic atlases that provide delineation of the target structure only, because it is more precise and provides a unique target point in the stereotactic space. This best stereotactic target is the point in the individualized atlas with the highest probability, meaning the highest probability of having the best target on the basis of the patients previously operated on. This best target is located in the hot STN, the size of which determines the precision of targeting. Because the size of the hot STN in comparison to the whole STN remains very small (1–2%) independent of whether or not lateral compensation is applied, target planning and execution have to be performed with high precision. The methodology presented, based on the PFA and on the functional volume, is general and can be applied to other structures and data sets. As numerous centers keep gathering large amounts of electrophysiological human and animal data, this work may facilitate opening new avenues in exploiting these data.
Published: 2005
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173. Subcortical loops through the basal ganglia

Author: John G. McHaffie, Peter Redgrave, Véronique Coizet, Terrence R. Stanford, Barry E. Stein, Department of Neurobiology and Anatomy, Wake Forest University, Department of Psychology [Sheffield], University of Sheffield [Sheffield], and Savasta, Marc
Subjects: Cholera Toxin, Central nervous system, MESH: Substantia Nigra, Brain mapping, Basal Ganglia, Midbrain, MESH: Basal Ganglia, Neural Pathways, Basal ganglia, medicine, [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology, Animals, Humans, MESH: Animals, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, MESH: Brain Mapping, MESH: Cholera Toxin, Cerebral Cortex, Brain Mapping, Neocortex, MESH: Humans, General Neuroscience, Superior colliculus, MESH: Neural Pathways, Anatomy, MESH: Cerebral Cortex, Substantia Nigra, medicine.anatomical_structure, MESH: Nerve Net, Cerebral cortex, Brainstem, Nerve Net, Psychology, Neuroscience
Abstract: International audience; Parallel, largely segregated, closed-loop projections are an important component of cortical-basal ganglia-cortical connectional architecture. Here, we present the hypothesis that such loops involving the neocortex are neither novel nor the first evolutionary example of closed-loop architecture involving the basal ganglia. Specifically, we propose that a phylogenetically older, closed-loop series of subcortical connections exists between the basal ganglia and brainstem sensorimotor structures, a good example of which is the midbrain superior colliculus. Insofar as this organization represents a general feature of brain architecture, cortical and subcortical inputs to the basal ganglia might act independently, co-operatively or competitively to influence the mechanisms of action selection.
Published: 2005
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174. Regional impairment of cerebrovascular reactivity and BOLD signal in adults after stroke

Author: D. Yves von Cramon, Stefan Zysset, Margret Hund-Georgiadis, Alexandre Krainik, Service d'Imagerie par Résonance Magnétique (IRM), CHU Grenoble, Neuroimagerie Fonctionnelle et Metabolique, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Max Planck Institute for Human Cognitive and Brain Sciences [Leipzig] (IMPNSC), Max-Planck-Gesellschaft, Daycare Clinic of Cognitive Neurology, Universität Leipzig [Leipzig], Collaboration, and Dojat, Michel
Subjects: Male, Pathology, Time Factors, genetic structures, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, MESH: Neurons, MESH: Frontal Lobe, MESH: Regression Analysis, 030218 nuclear medicine & medical imaging, Brain Ischemia, MESH: Magnetic Resonance Imaging, MESH: Hyperventilation, 0302 clinical medicine, Cerebellum, Ischaemic stroke, Image Processing, Computer-Assisted, Hyperventilation, Stroke, MESH: Brain Mapping, Neurons, MESH: Aged, Brain Mapping, MESH: Middle Aged, medicine.diagnostic_test, Cerebral infarction, Motor Cortex, MESH: Brain Ischemia, Middle Aged, Magnetic Resonance Imaging, MESH: Image Processing, Computer-Assisted, MESH: Case-Control Studies, Frontal Lobe, Cardiology, Regression Analysis, Female, Cardiology and Cardiovascular Medicine, psychological phenomena and processes, MESH: Oxygen, Adult, medicine.medical_specialty, behavioral disciplines and activities, MESH: Motor Cortex, MESH: Stroke, Central nervous system disease, 03 medical and health sciences, MESH: Software, Cerebrovascular reactivity, Internal medicine, medicine, [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology, Bold fmri, Humans, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Motor activity, Aged, Advanced and Specialized Nursing, MESH: Humans, business.industry, MESH: Time Factors, MESH: Adult, medicine.disease, MESH: Male, MESH: Cerebellum, Oxygen, [SDV.IB.IMA] Life Sciences [q-bio]/Bioengineering/Imaging, nervous system, Case-Control Studies, Neurology (clinical), business, Functional magnetic resonance imaging, MESH: Female, 030217 neurology & neurosurgery, Software
Abstract: Background and Purpose— Comparative studies across populations using functional magnetic resonance imaging (fMRI) rely on a similar relationship between blood oxygen level-dependent (BOLD) signal and neural activity. However, in elderly and patients with cerebrovascular disease, impaired cerebrovascular dynamics and neurovascular coupling may explain differences in BOLD contrast across populations and brain regions. The purpose of the study was to determine whether poststroke patients have regional heterogeneities of cerebrovascular reactivity (CVR) and their potential influence on voxel-wise motor-related BOLD signal. Methods— Using fMRI, 8 fully recovered patients from stroke in the frontal lobe without cortical lesion in the regions of interest located in the primary sensorimotor cortex (SMC), supplementary motor area (SMA), and cerebellum (CRB) were compared with 8 healthy subjects. Motor-related BOLD signal changes (%SC) were evaluated during simple unimanual and bimanual tasks, and CVR was evaluated during hyperventilation (HV). Analyses were performed using Lipsia software in SMC, SMA, and CRB. Results— In controls, amplitudes of BOLD signal were symmetrical in all regions of interest during all motor tasks and HV. In patients, %SC was decreased in SMC and SMA of the lesioned hemisphere despite their apparent anatomical integrity for all tasks. Impaired CVR was a predictor of impaired motor-related BOLD response in the SMC during contralateral movements (β=−1.87; R =−0.75; P =0.03). Conclusions— These preliminary findings suggest that CVR heterogeneities may account for task-related BOLD signal changes in patients after stroke.
Published: 2005
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175. Subliminal convergence of Kanji and Kana words: further evidence for functional parcellation of the posterior temporal cortex in visual word perception

Author: Denis Le Bihan, Kimihiro Nakamura, Sid Kouider, Stanislas Dehaene, Antoinette Jobert, Research Institute for Applied Mechanics, Kyushu University, Kyushu University [Fukuoka], Human Brain Research Center [Kyoto] (HBRC), Kyoto University [Kyoto], Service Hospitalier Frédéric Joliot (SHFJ), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Neuroimagerie cognitive (LCogn), Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institutions et Dynamiques Historiques de l'Economie (IDHE), École normale supérieure - Cachan (ENS Cachan)-Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris 8 Vincennes-Saint-Denis (UP8)-Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS), Service NEUROSPIN (NEUROSPIN), IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Kyushu University, Kyoto University, Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Adult, Kanji, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Cognitive Neuroscience, education, Subliminal Stimulation, MESH: Reading, behavioral disciplines and activities, 050105 experimental psychology, MESH: Magnetic Resonance Imaging, 03 medical and health sciences, 0302 clinical medicine, Reference Values, Reaction Time, medicine, Humans, MESH: Temporal Lobe, 0501 psychology and cognitive sciences, Visual Word, Visual word form area, MESH: Brain Mapping, Language, Temporal cortex, Brain Mapping, MESH: Verbal Behavior, MESH: Humans, medicine.diagnostic_test, Verbal Behavior, 05 social sciences, Subliminal stimuli, MESH: Subliminal Stimulation, MESH: Reference Values, MESH: Adult, Kana, Magnetic Resonance Imaging, Temporal Lobe, MESH: Reaction Time, Reading, MESH: Language, Psychology, Functional magnetic resonance imaging, Priming (psychology), 030217 neurology & neurosurgery, Cognitive psychology
Abstract: Recent evidence has suggested that the human occipito-temporal region comprises several subregions, each sensitive to a distinct processing level of visual words. To further explore the functional architecture of visual word recognition, we employed a subliminal priming method with functional magnetic resonance imaging (fMRI) during semantic judgments of words presented in two different Japanese scripts, Kanji and Kana. Each target word was preceded by a subliminal presentation of either the same or a different word, and in the same or a different script. Behaviorally, word repetition produced significant priming regardless of whether the words were presented in the same or different script. At the neural level, this cross-script priming was associated with repetition suppression in the left inferior temporal cortex anterior and dorsal to the visual word form area hypothesized for alphabetical writing systems, suggesting that cross-script convergence occurred at a semantic level. fMRI also evidenced a shared visual occipito-temporal activation for words in the two scripts, with slightly more mesial and right-predominant activation for Kanji and with greater occipital activation for Kana. These results thus allow us to separate script-specific and script-independent regions in the posterior temporal lobe, while demonstrating that both can be activated subliminally.
Published: 2005
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176. Condition-dependent functional connectivity: syntax networks in bilinguals

Author: Denis Le Bihan, Christophe Pallier, Silke Dodel, Vincent ElKouby, Jean-Baptiste Poline, Narly Golestani, Neuroimagerie cognitive (LCogn), Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Santé et de la Recherche Médicale (INSERM), Service Hospitalier Frédéric Joliot (SHFJ), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Service NEUROSPIN (NEUROSPIN), IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Human Brain Research Center [Kyoto] (HBRC), Kyoto University [Kyoto], Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Kyoto University
Subjects: Computer science, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Concept Formation, MESH: Language Tests, MESH: Multilingualism, Models, Neurological, MESH: Psychophysiology, Multilingualism, Brain mapping, 050105 experimental psychology, General Biochemistry, Genetics and Molecular Biology, MESH: Magnetic Resonance Imaging, 03 medical and health sciences, MESH: Brain, 0302 clinical medicine, MESH: Models, Neurological, Image Processing, Computer-Assisted, Humans, 0501 psychology and cognitive sciences, MESH: Brain Mapping, Brain Mapping, Language Tests, MESH: Humans, Syntax (programming languages), Language production, 05 social sciences, Psychophysiological Interaction, Brain, MESH: Concept Formation, Magnetic Resonance Imaging, MESH: Image Processing, Computer-Assisted, Functional imaging, MESH: France, Variation (linguistics), France, General Agricultural and Biological Sciences, 030217 neurology & neurosurgery, Sentence, Psychophysiology, Research Article, Cognitive psychology
Abstract: This paper introduces a method to study the variation of brain functional connectivity networks with respect to experimental conditions in fMRI data. It is related to the psychophysiological interaction technique introduced by Friston et al . and extends to networks of correlation modulation (CM networks). Extended networks containing several dozens of nodes are determined in which the links correspond to consistent correlation modulation across subjects. In addition, we assess inter-subject variability and determine networks in which the condition-dependent functional interactions can be explained by a subject-dependent variable. We applied the technique to data from a study on syntactical production in bilinguals and analysed functional interactions differentially across tasks (word reading or sentence production) and across languages. We find an extended network of consistent functional interaction modulation across tasks, whereas the network comparing languages shows fewer links. Interestingly, there is evidence for a specific network in which the differences in functional interaction across subjects can be explained by differences in the subjects' syntactical proficiency. Specifically, we find that regions, including ones that have previously been shown to be involved in syntax and in language production, such as the left inferior frontal gyrus, putamen, insula, precentral gyrus, as well as the supplementary motor area, are more functionally linked during sentence production in the second, compared with the first, language in syntactically more proficient bilinguals than in syntactically less proficient ones. Our approach extends conventional activation analyses to the notion of networks, emphasizing functional interactions between regions independently of whether or not they are activated. On the one hand, it gives rise to testable hypotheses and allows an interpretation of the results in terms of the previous literature, and on the other hand, it provides a basis for studying the structure of functional interactions as a whole, and hence represents a further step towards the notion of large-scale networks in functional imaging.
Published: 2005
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177. Disorganized somatotopy in the putamen of patients with focal hand dystonia

Author: M. Vidailhet, Christine Delmaire, Sophie Sangla, Sabine Meunier, Line Garnero, Emmanuel Gerardin, S. Tezenas du Montcel, Stéphane Lehéricy, J.-F. Mangin, Alexandre Krainik, Neuro-anatomie fonctionnelle du comportement et de ses troubles, Université Pierre et Marie Curie - Paris 6 ( UPMC ) -IFR70-Institut National de la Santé et de la Recherche Médicale ( INSERM ), Departement de neuroradiologie, CHU La Tronche, Neuroimagerie Fonctionnelle et Metabolique, Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ), Grenoble Institut des Neurosciences ( GIN ), Institut National de la Santé et de la Recherche Médicale ( INSERM ) -CHU Grenoble-Université Joseph Fourier - Grenoble 1 ( UJF ), Département de neuro-radiologie, Université Joseph Fourier - Grenoble 1 ( UJF ) -CHU Grenoble, Service de biostatistiques et information médicale [CHU Pitié-Salpêtrière], Assistance publique - Hôpitaux de Paris (AP-HP)-CHU Pitié-Salpêtrière [APHP], Génétique épidémiologique et structures des populations humaines ( Inserm U535 ), Epidémiologie, sciences sociales, santé publique ( IFR 69 ), Université Panthéon-Sorbonne ( UP1 ) -Université Paris-Sud - Paris 11 ( UP11 ) -École des hautes études en sciences sociales ( EHESS ) -Assistance publique - Hôpitaux de Paris (AP-HP)-Université Paris Descartes - Paris 5 ( UPD5 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Panthéon-Sorbonne ( UP1 ) -Université Paris-Sud - Paris 11 ( UP11 ) -École des hautes études en sciences sociales ( EHESS ) -Assistance publique - Hôpitaux de Paris (AP-HP)-Université Paris Descartes - Paris 5 ( UPD5 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ), Institut Européen des membranes ( IEM ), Centre National de la Recherche Scientifique ( CNRS ) -Ecole Nationale Supérieure de Chimie de Montpellier ( ENSCM ) -Université Montpellier 2 - Sciences et Techniques ( UM2 ) -Université de Montpellier ( UM ), Physiologie et physiopathologie de la motricité chez l'homme, Neurobiologie des processus adaptatifs ( NPA ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Centre de Recherche en Neurobiologie cellulaire et moléculaire, Faculté de Médecine de Liège, Department of Physiology, Transnationale Universiteit Limburg/Limburgs, Center for Cellular and Molecular Neuroscience, Université de Liège, Laboratoire de Physique de l'Université de Bourgogne ( LPUB ), Université de Bourgogne ( UB ) -Centre National de la Recherche Scientifique ( CNRS ), Center for Neuroscience and Behavioral Medicine, Children's National Medical Center, Service de neurologie 1 [CHU Pitié-Salpétrière], Neurosciences cognitives et imagerie cérébrale ( NCIC ), Centre National de la Recherche Scientifique ( CNRS ), Service de neurologie [Univ. Paris VI], Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Assistance publique - Hôpitaux de Paris (AP-HP)-CHU Saint-Antoine [APHP], Neurologie et thérapeutique expérimentale, Service de neuro-radiologie [CHU Pitié-Salpêtrière], Centre de Neuro-Imagerie de Recherche ( CENIR ), Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR70-Institut National de la Santé et de la Recherche Médicale (INSERM), Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Grenoble Institut des Neurosciences (GIN), Université Joseph Fourier - Grenoble 1 (UJF)-CHU Grenoble, CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Génétique épidémiologique et structures des populations humaines (Inserm U535), Epidémiologie, sciences sociales, santé publique (IFR 69), Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris-Sud - Paris 11 (UP11)-École des hautes études en sciences sociales (EHESS)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris-Sud - Paris 11 (UP11)-École des hautes études en sciences sociales (EHESS)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut Européen des membranes (IEM), Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Neurobiologie des processus adaptatifs (NPA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique de l'Université de Bourgogne (LPUB), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Neurosciences cognitives et imagerie cérébrale (NCIC), Centre National de la Recherche Scientifique (CNRS), CHU Saint-Antoine [AP-HP], Center for NeuroImaging Research-Human MRI Neuroimaging core facility for clinical research [ICM Paris] (CENIR), Institut du Cerveau = Paris Brain Institute (ICM), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Département de Biostatistique, Santé Publique et Information Médicale [CHU Pitié-Salpêtrière] (BIOSPIM ), Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM), Service de Neurologie [CHU Pitié-Salpêtrière], IFR70-CHU Pitié-Salpêtrière [AP-HP], Service de neurologie [Saint-Antoine], Université Pierre et Marie Curie - Paris 6 (UPMC)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Saint-Antoine [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR70-Université Pierre et Marie Curie - Paris 6 (UPMC), Service de Neuroradiologie [CHU Pitié-Salpêtrière], Centre de Neuro-Imagerie de Recherche (CENIR), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), CHU Grenoble-Université Joseph Fourier - Grenoble 1 (UJF), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Service de neurologie [CHU Saint-Antoine], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Institut du Cerveau et de la Moëlle Epinière = Brain and Spine Institute (ICM), Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], and Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Male, MESH : Lip, MESH : Brain Mapping, MESH : Aged, Striatum, Neurological disorder, Brain mapping, Functional Laterality, MESH: Magnetic Resonance Imaging, MESH: Putamen, 0302 clinical medicine, MESH : Neural Pathways, Neural Pathways, MESH : Female, MESH: Arm, MESH: Brain Mapping, Dystonia, Cerebral Cortex, MESH: Aged, 0303 health sciences, Brain Mapping, MESH: Middle Aged, Putamen, Anatomy, MESH: Lip, MESH : Hand, Middle Aged, MESH : Adult, Magnetic Resonance Imaging, MESH: Predictive Value of Tests, medicine.anatomical_structure, Cerebral cortex, Dystonic Disorders, Arm, MESH : Cerebral Cortex, Female, Adult, MESH : Male, MESH : Arm, MESH: Hand, Central nervous system disease, 03 medical and health sciences, MESH : Dystonic Disorders, Predictive Value of Tests, MESH : Magnetic Resonance Imaging, medicine, Humans, MESH : Middle Aged, MESH: Functional Laterality, MESH : Predictive Value of Tests, MESH : Functional Laterality, 030304 developmental biology, Aged, MESH: Humans, [SDV.BA.MVSA]Life Sciences [q-bio]/Animal biology/Veterinary medicine and animal Health, business.industry, MESH: Neural Pathways, MESH : Humans, MESH: Dystonic Disorders, MESH: Adult, medicine.disease, Hand, Lip, MESH: Male, MESH: Cerebral Cortex, nervous system, MESH : Putamen, Neurology (clinical), [ SDV.BA.MVSA ] Life Sciences [q-bio]/Animal biology/Veterinary medicine and animal Health, business, MESH: Female, 030217 neurology & neurosurgery, Dystonic disorder
Abstract: International audience; OBJECTIVE: To explore the selectivity of neuronal somatotopic representation in the striatum of patients with unilateral task-specific dystonia of the right arm. MATERIALS AND METHODS: The authors used fMRI in 14 right-handed dystonic subjects to examine putaminal organization. Subjects performed flexion/extension of the right and left fingers and toes, and contraction of the lips. RESULTS: Compared to healthy volunteer subjects, dystonic subjects had altered somatotopic organization in the left putamen, contralateral to the affected hand. Disease severity correlated with underactivation and decreased distance between right hand and lip representations. In the right putamen, ipsilateral to the affected hand, the somatotopic organization was not altered but disease severity also correlated with reduced distances between limbs. CONCLUSION: In dystonia there may be a dedifferentiation of the normally segregated cortico-subcortical sensorimotor maps in the putamen, which may contribute to the loss of functional selectivity of muscle activity observed in these dystonic subjects.
Published: 2005
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178. Assessment of the early organization and maturation of infants' cerebral white matter fiber bundles: a feasibility study using quantitative diffusion tensor imaging and tractography

Author: Y. Cointepas, Ghislaine Dehaene-Lambertz, D. Le Bihan, Jessica Dubois, Lucie Hertz-Pannier, Service Hospitalier Frédéric Joliot (SHFJ), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), IFR49 - Neurospin - CEA, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Épilepsie de l'enfant et plasticité cérébrale (Inserm U663), Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM), CHU Necker - Enfants Malades [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Neuroimagerie cognitive (LCogn), Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Santé et de la Recherche Médicale (INSERM), Le Bihan, Denis, Département de radiothérapie, CRLCC Val d'Aurelle - Paul Lamarque, Institut de recherche en cancérologie de Montpellier (IRCM - U896 Inserm - UM1), Université Montpellier 1 (UM1)-CRLCC Val d'Aurelle - Paul Lamarque-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM), Institut d'imagerie neurofonctionnelle (IIN), Institut National de la Santé et de la Recherche Médicale (INSERM)-Ecole Nationale Supérieure des Télécommunications (ENST)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École des hautes études en sciences sociales (EHESS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Traitement et Communication de l'Information (LTCI), Télécom ParisTech-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS), Service NEUROSPIN (NEUROSPIN), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, IFR de Neuroimagerie Fonctionnelle (IFR 49), Human Brain Research Center [Kyoto] (HBRC), and Kyoto University [Kyoto]
Subjects: Male, Spinothalamic Tracts, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Pyramidal Tracts, MESH: Pyramidal Tracts, Corpus callosum, Brain mapping, Nerve Fibers, Myelinated, 030218 nuclear medicine & medical imaging, 0302 clinical medicine, MESH: Spinothalamic Tracts, Reference Values, Neural Pathways, Image Processing, Computer-Assisted, Cingulum (brain), MESH: Brain Mapping, Cerebral Cortex, Brain Mapping, MESH: Reference Values, Age Factors, Brain, MESH: Image Processing, Computer-Assisted, MESH: Infant, MESH: Nerve Fibers, Myelinated, medicine.anatomical_structure, Neurology, Female, Psychology, Algorithms, Tractography, Cognitive Neuroscience, MESH: Algorithms, MESH: Imaging, Three-Dimensional, MESH: Diffusion Magnetic Resonance Imaging, White matter, MESH: Brain, 03 medical and health sciences, Imaging, Three-Dimensional, Fractional anisotropy, medicine, Humans, MESH: Infant Behavior, Dominance, Cerebral, MESH: Age Factors, MESH: Humans, Pyramidal tracts, MESH: Neural Pathways, Infant, MESH: Dominance, Cerebral, MESH: Cerebral Cortex, MESH: Male, [SDV.IB.IMA] Life Sciences [q-bio]/Bioengineering/Imaging, Diffusion Magnetic Resonance Imaging, Infant Behavior, MESH: Anisotropy, Anisotropy, MESH: Female, Neuroscience, 030217 neurology & neurosurgery, Diffusion MRI
Abstract: International audience; The human infant is particularly immature at birth and brain maturation, with the myelination of white matter fibers, is protracted until adulthood. Diffusion tensor imaging offers the possibility to describe non invasively the fascicles spatial organization at an early stage and to follow the cerebral maturation with quantitative parameters that might be correlated with behavioral development. Here, we assessed the feasibility to study the organization and maturation of major white matter bundles in eighteen 1- to 4-month-old healthy infants, using a specific acquisition protocol customized to the immature brain (with 15 orientations of the diffusion gradients and a 700 s mm(-2)b factor). We were able to track most of the main fascicles described at later ages despite the low anisotropy of the infant white matter, using the FACT algorithm. This mapping allows us to propose a new method of quantification based on reconstructed tracts, split between specific regions, which should be more sensitive to specific changes in a bundle than the conventional approach, based on regions-of-interest. We observed variations in fractional anisotropy and mean diffusivity over the considered developmental period in most bundles (corpus callosum, cerebellar peduncles, cortico-spinal tract, spino-thalamic tract, capsules, radiations, longitudinal and uncinate fascicles, cingulum). The results are in good agreement with the known stages of white matter maturation and myelination, and the proposed approach might provide important insights on brain development.
Published: 2005
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179. Intact hemispheric specialization for spatial and shape working memory in schizophrenia

Author: Stephan Heckers, Stéphanie Dubal, Kristen A. Lindgren, Philip S. Holzman, Dara S. Manoach, Donald C. Goff, Michael J. Coleman, Nathan S. White, Vulnérabilité Adaptation et Psychopathologie (VAP), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Male, MESH: Magnetic Resonance Imaging, Discrimination Learning, 0302 clinical medicine, Reference Values, Attention, Prefrontal cortex, MESH: Brain Mapping, Brain Mapping, MESH: Middle Aged, 05 social sciences, MESH: Reference Values, Cognition, Middle Aged, Magnetic Resonance Imaging, Psychiatry and Mental health, medicine.anatomical_structure, Memory, Short-Term, Pattern Recognition, Visual, Schizophrenia, Laterality, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Female, Schizophrenic Psychology, Psychology, MESH: Schizophrenic Psychology, Adult, Ventrolateral prefrontal cortex, MESH: Orientation, Prefrontal Cortex, MESH: Pattern Recognition, Visual, MESH: Imaging, Three-Dimensional, 050105 experimental psychology, MESH: Memory, Short-Term, 03 medical and health sciences, Imaging, Three-Dimensional, Functional neuroimaging, Orientation, medicine, Humans, 0501 psychology and cognitive sciences, Dominance, Cerebral, Biological Psychiatry, MESH: Attention, MESH: Humans, Working memory, MESH: Adult, MESH: Dominance, Cerebral, medicine.disease, MESH: Discrimination Learning, MESH: Schizophrenia, MESH: Male, Functional imaging, MESH: Prefrontal Cortex, Neuroscience, MESH: Female, 030217 neurology & neurosurgery
Abstract: International audience; OBJECTIVE: Using functional MRI, we investigated whether, like healthy subjects, patients with schizophrenia show a relative hemispheric specialization in ventrolateral prefrontal cortex (PFC) for spatial and shape working memory (WM). We hypothesized that reduced specialization in schizophrenia would reflect a failure to adopt optimal domain-specific strategies and would contribute to WM deficits. METHODS: Twelve healthy subjects and 16 schizophrenia patients performed spatial and shape WM tasks and a non-WM control task. Direct comparisons of the spatial and shape WM tasks assessed specialization. RESULTS: Despite deficient WM performance, both patients and controls showed a relative hemispheric specialization in ventrolateral PFC for spatial (right) and shape (left) WM and did not differ in this regard. CONCLUSIONS: The finding of intact hemispheric specialization in ventrolateral PFC suggests that patients employ the same domain-specific strategies as healthy subjects during spatial and shape WM. Rather than reflecting a failure to adopt the optimal strategy, we hypothesize that WM deficits in schizophrenia reflect impairments of executive processes that are required for WM performance regardless of domain. These processes are associated with activity in the dorsolateral PFC, a region that has been repeatedly implicated in studies of WM.
Published: 2005
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180. Involvement of the basal ganglia in refractory epilepsy: an 18F-fluoro-L-DOPA PET study using 2 methods of analysis

Author: Bouilleret, Viviane, Semah, Franck, Biraben, Arnaud, Taussig, Delphine, Chassoux, Francine, Syrota, André, Ribeiro, Maria-João, Service Hospitalier Frédéric Joliot (SHFJ), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service de neurophysiologie clinique et d'épileptologie, Université Paris-Sud - Paris 11 (UP11)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Bicêtre, Service de neurologie [Rennes], Université de Rennes (UR), Service de Neurochirurgie, Hôpital Saint-Anne, Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Hôpital Bicêtre-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Université Paris-Sud - Paris 11 (UP11), Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)
Subjects: Adult, Male, Drug Resistance, MESH: Algorithms, Sensitivity and Specificity, MESH: Dihydroxyphenylalanine, Basal Ganglia, MESH: Basal Ganglia, MESH: Anticonvulsants, Image Interpretation, Computer-Assisted, MESH: Reproduc, Humans, MESH: Brain Mapping, Brain Mapping, Epilepsy, MESH: Middle Aged, MESH: Humans, Reproducibility of Results, MESH: Adult, Middle Aged, MESH: Male, MESH: Positron-Emission Tomography, Dihydroxyphenylalanine, Positron-Emission Tomography, MESH: Epilepsy, MESH: Drug Resistance, Anticonvulsants, Female, [SDV.IB]Life Sciences [q-bio]/Bioengineering, Radiopharmaceuticals, MESH: Image Interpretation, Computer-Assisted, MESH: Female, Algorithms, MESH: Radiopharmaceuticals
Abstract: Studies in animal models and epileptic patients have led to the suggestion that the basal ganglia (BG) are involved in seizures. PET with 6-18F-L-3,4-fluorodihydroxyphenylalanine (18F-fluoro-L-DOPA) has recently demonstrated a reduction of striatal dopamine uptake in drug-resistant epileptic patients with ring chromosome 20 (r20) using a multiple-time graphical analysis. The aim of the present study was to evaluate the involvement of dopamine in other epileptic syndromes using a multiple-time graphical analysis and the all-brain statistical parametric mapping (SPM) analysis. METHODS: Patients with drug-resistant epilepsy were divided into 3 groups: group 1, with r20 epilepsy (n = 16; mean age +/- SD, 21.5 +/- 5.4 y); group 2, with resistant generalized "absence-like" epilepsy (n = 10; mean age, 32.3 +/- 11.4 y); and group 3, with drug-resistant temporal lobe epilepsy with hippocampal sclerosis (n = 9; mean age, 35.2 +/- 10.3 y). We compared 2 strategies of analysis of the 18F-fluoro-L-DOPA uptake constant (K(i), min(-1)) in BG using a multiple-time graphical analysis using regions of interest (the gold-standard method) and an SPM analysis using a voxel-by-voxel statistical t test to avoid a priori hypotheses in the analysis. Each epileptic group was compared with a group of healthy volunteers (n = 10; mean age, 45.1 +/- 16.5 y). RESULTS: A decrease of the mean K(i) value was observed in the striatum in all groups of patients with both types of analysis. With multiple-time graphical analysis, the reduction was evident using the averaged K(i) values over both hemispheres in each BG. Unilateral decreases in each BG were detected in SPM analysis. A ratio of decrease of 18F-fluoro-L-DOPA uptake was observed in the 3 groups of patients. Only the SPM analysis showed a decrease of 18F-fluoro-L-DOPA uptake ipsilateral to the seizure side in patients with temporal lobe epilepsy. Moreover, the all-brain SPM analysis showed a decrease of 18F-fluoro-L-DOPA uptake in the substantia nigra bilaterally (P < 0.001). CONCLUSION: This result confirms the involvement of dopamine neurotransmission in seizure control related to the type of epileptic syndrome. The difference in epileptic types may depend in part on the seizure frequency.
Published: 2005

181. Role of synaptic and intrinsic membrane properties in short-term receptive field dynamics in cat area 17

Author: David A. McCormick, Lionel G. Nowak, Maria V. Sanchez-Vives, Centre de recherche cerveau et cognition (CERCO), Institut des sciences du cerveau de Toulouse. (ISCT), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Neurobiology, School of Medicine, Yale University [New Haven], Instituto de Neurociencias de Alicante- CSIC, and Universidad Miguel Hernández [Elche] (UMH)
Subjects: genetic structures, Photic Stimulation, MESH: Neurons, MESH: Afterimage, receptive field, Action Potentials, Stimulation, MESH: Synapses, Membrane Potentials, 0302 clinical medicine, MESH: Animals, MESH: Neuronal Plasticity, Scotoma, MESH: Action Potentials, MESH: Brain Mapping, MESH: Contrast Sensitivity, Visual Cortex, Membrane potential, Neurons, 0303 health sciences, Brain Mapping, Neuronal Plasticity, General Neuroscience, dynamics, Hyperpolarization (biology), Adaptation, Physiological, Afterimage, medicine.anatomical_structure, cortex, MESH: Photic Stimulation, visual, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], MESH: Cats, vision, Materials science, Behavioral/Systems/Cognitive, Stimulus (physiology), Contrast Sensitivity, 03 medical and health sciences, gain control, Neuroplasticity, medicine, MESH: Scotoma, MESH: Membrane Potentials, Animals, 030304 developmental biology, Cell Membrane, MESH: Visual Cortex, MESH: Adaptation, Physiological, Visual cortex, Receptive field, plasticity, Synapses, Cats, sense organs, Neuroscience, 030217 neurology & neurosurgery, MESH: Cell Membrane
Abstract: International audience; We examined the mechanisms through which the prolonged presentation of either a high-contrast stimulus or an artificial scotoma [equivalent to the stimulation of the receptive field (RF) surround] induces changes in the RF properties of neurons intracellularly recorded in cat primary visual cortex. Discharge and synaptic RFs were quantitatively characterized using bright and dark bars randomly flashed in various positions. Compared with the lack of stimulation (0% contrast for 15-30 s), stimulation with high-contrast sine-wave gratings (15-30 s) was followed by a strong reduction in gain and a weak but significant reduction in width of spike discharge RFs. These reductions were accompanied by a membrane potential hyperpolarization, a decrease of synaptic RF width, and varying changes of synaptic RF gain. Passive hyperpolarization by DC injection also produced significant reduction in the width and gain of discharge RF. Mimicking, in single neurons, high-contrast stimulation with high-intensity current injection also induced a membrane potential hyperpolarization, whose amplitude was correlated with discharge RF gain and width changes. Recovery from adaptation to high-contrast stimulation during the period of gray screen or scotoma presentation was associated with an increase in gain and discharge RF size. Stimulation of the RF surround with an artificial scotoma did not have any additional aftereffects over those of adaptation to a gray screen, indicating that the contraction and expansion of RF gain and size are attributable to intrinsic and synaptic mechanisms underlying adaptation and de-adaptation to strong visual stimuli.
Published: 2005
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182. The interaction between magnetization transfer and blood-oxygen-level-dependent effects

Author: Jinyuan Zhou, Peter C.M. van Zijl, Jean Francois Payen, Division of MRI Research, Department of Radiology, Johns Hopkins University School of Medicine, F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Clinique de réanimation médicale, Université Joseph Fourier - Grenoble 1 (UJF)-CHU Grenoble-Hôpital Michallon, NIH/NIBIB, Grant Number: EB02666 NIH/NINDS, Grant Number: NIH/NIBIB EB02634, NIH/NIBIB EB04130 NIH/NCRR, Grant Number: RR15241 Whitaker Foundation, and Dojat, Michel
Subjects: genetic structures, magnetization transfer, MESH: Rats, Sprague-Dawley, MESH: Carbon Dioxide, Brain mapping, 030218 nuclear medicine & medical imaging, MESH: Magnetic Resonance Imaging, Rats, Sprague-Dawley, 0302 clinical medicine, Nuclear magnetic resonance, Hypocapnia, MESH: Animals, Saturation (magnetic), MESH: Brain Mapping, Brain Mapping, Blood-oxygen-level dependent, medicine.diagnostic_test, Chemistry, fMRI, Brain, MESH: Cerebrovascular Circulation, Magnetic Resonance Imaging, Cerebrovascular Circulation, medicine.symptom, Hypercapnia, psychological phenomena and processes, MESH: Oxygen, MESH: Rats, CBV, behavioral disciplines and activities, 03 medical and health sciences, Magnetics, MESH: Brain, Image Interpretation, Computer-Assisted, medicine, [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology, Animals, Radiology, Nuclear Medicine and imaging, MESH: Magnetics, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Magnetization transfer, Magnetic resonance imaging, hypercapnia, Carbon Dioxide, medicine.disease, Rats, Oxygen, hypocapnia, nervous system, MT, Functional magnetic resonance imaging, MESH: Image Interpretation, Computer-Assisted, 030217 neurology & neurosurgery, BOLD
Abstract: International audience; Low-power off-resonance spin-echo magnetization transfer (MT) imaging experiments with a long repetition time (TR) were performed on rat brain for a range of arterial PCO2 levels. The measured magnetization transfer ratio decreased with increased arterial PCO2 levels. When performing blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI)-type data analysis in which signal intensities were normalized to the normocapnic state, the CO2-based BOLD effect was much stronger with than without saturation. This increased effect is a consequence of the fact that the MT effect reduces the signal intensity in tissue more than in blood, thereby amplifying the contribution of the intravascular BOLD signal change to the overall BOLD effect. The results offer a potential approach to measure absolute cerebral blood volume in vivo and to amplify the BOLD effects for fMRI studies.
Published: 2005
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183. Event-related P3a and P3b in response to unpredictable emotional stimuli

Author: Pascal Hot, Laetitia Silvert, Henrique Sequeira, Sylvain Delplanque, Laboratoire de psychologie sociale et de psychologie cognitive (LAPSCO), Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Laboratoire de Neurosciences Fonctionnelles et Pathologies (LNFP), Université de Lille, Droit et Santé-Centre National de la Recherche Scientifique (CNRS), and Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Male, Eye Movements, MESH: Frontal Lobe, MESH: Cognition, Evoked Potentials/physiology, Memory/physiology, Cognition, 0302 clinical medicine, MESH: Blinking, MESH: Eye Movements, Parietal Lobe, Arousal/physiology, Affect/physiology, MESH: Memory, Temporal Lobe/physiology, Evoked Potentials, Oddball paradigm, Cognition/physiology, Occipital Lobe/physiology, MESH: Brain Mapping, Brain Mapping, MESH: Parietal Lobe, General Neuroscience, 05 social sciences, Electroencephalography, MESH: Affect, MESH: Neural Inhibition, Temporal Lobe, Frontal Lobe, MESH: Evoked Potentials, Neuropsychology and Physiological Psychology, Female, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Occipital Lobe, Arousal, Psychology, Cognitive psychology, MESH: Occipital Lobe, Adult, Stimulus (physiology), Brain Mapping/instrumentation, 050105 experimental psychology, 03 medical and health sciences, P3a, Memory, Event-related potential, P3b, MESH: Electroencephalography, Humans, Nerve Net/physiology, MESH: Temporal Lobe, 0501 psychology and cognitive sciences, Valence (psychology), Parietal Lobe/physiology, MESH: Humans, Blinking, Neural Inhibition/physiology, MESH: Arousal, Neural Inhibition, MESH: Adult, Blinking/physiology, Eye Movements/physiology, Frontal Lobe/physiology, MESH: Male, Affect, MESH: Nerve Net, Nerve Net, MESH: Female, 030217 neurology & neurosurgery
Abstract: International audience; In natural situations, unpredictable events processing often interacts with the ongoing cognitive activities. In a similar manner, the insertion of deviant unpredictable stimuli into a classical oddball task evokes both the P3a and P3b event-related potentials (ERPs) components that are, respectively, thought to index reallocation of attentional resources or inhibitory process and memory updating mechanism. This study aims at characterising the influence of the emotional arousal and valence of a deviant and unpredictable non-target stimulus on these components. ERPs were recorded from 28 sites during a visual three-stimulus oddball paradigm. Unpleasant, neutral and pleasant pictures served as non-target unpredictable items and subjects were asked to realize a perceptually difficult standard/target discrimination task. A temporal principal component analysis (PCA) allowed us to show that non-target pictures elicited both a P3a and a P3b. Moreover, the P3b component was modulated by the emotional arousal and the valence of the pictures. Thus, the memory updating process may be modulated by the affective arousal and valence of unpredictable disturbing stimuli, even if the task does not require any explicit emotional categorization.
Published: 2005
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184. Recollection of vivid memories after perirhinal region stimulations: synchronization in the theta range of spatially distributed brain areas

Author: Emmanuel J. Barbeau, Michel Poncet, Patrick Chauvel, Fabrice Bartolomei, Roderick Duncan, Fabrice Wendling, Jean Régis, Centre de recherche cerveau et cognition (CERCO), Institut des sciences du cerveau de Toulouse. (ISCT), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut des sciences du cerveau de Toulouse. (ISCT), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Male, Hippocampus, Electroencephalography, Neuropsychological Tests, Functional Laterality, Stereotaxic Techniques, Behavioral Neuroscience, 0302 clinical medicine, Cortex (anatomy), Perirhinal cortex, MESH: Memory, MESH: Brain Mapping, Temporal cortex, Brain Mapping, medicine.diagnostic_test, 05 social sciences, MESH: Electric Stimulation, MESH: Neuropsychological Tests, MESH: Comparative Study, MESH: Case-Control Studies, Temporal Lobe, medicine.anatomical_structure, MESH: Photic Stimulation, MESH: Epilepsy, Temporal Lobe, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Psychology, Adult, Cognitive Neuroscience, MESH: Stereotaxic Techniques, Experimental and Cognitive Psychology, 050105 experimental psychology, MESH: Laterality, 03 medical and health sciences, Visual memory, Memory, MESH: Electroencephalography, medicine, Humans, MESH: Temporal Lobe, 0501 psychology and cognitive sciences, MESH: Humans, Recall, MESH: Adult, Electric Stimulation, MESH: Male, Epilepsy, Temporal Lobe, Brain stimulation, Case-Control Studies, Neuroscience, 030217 neurology & neurosurgery, Photic Stimulation
Abstract: Electrical stimulation of the temporal cortex in patients with epilepsy sometimes elicits experiential phenomena such as recollection of vivid memories. The neurophysiological substrate of such phenomena is poorly understood. Furthermore, the relation between the site of stimulation and the type of memory elicited has only recently started to be investigated. We investigated these issues in patient FGA who had intracerebral electrodes stereotaxically implanted in the right temporal lobe for investigation of drug-resistant epilepsy. We report the results of electrical stimulations of the perirhinal region. Two stimulations elicited experiential phenomena consisting of visual memories that belonged to FGA's past, but which were not related to any particular episode. These visual memories consisted of objects or of details of objects. These two stimulations were contrasted with other stimulations in the same subhippocampal region. Cross-correlation analysis of the depth-EEG signals filtered in frequency sub-bands revealed that experiential phenomena occurred only when the various brain structures involved in the after-discharge were synchronized in the theta range. These structures included the perirhinal region, the hippocampus, other limbic structures as well as a primary visual area. Our results suggest that recollection of vivid memory after electric stimulation of the cortex may rely on wide networks of brain areas that transiently synchronize. These results also highlight the role of the perirhinal region in human memory. Experiential phenomena are rarely obtained after brain stimulation. Replication of these results is thus required due to the small number of observations reported.
Published: 2005
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185. Involvement of the basal ganglia in refractory epilepsy: an 18F-fluoro-L-DOPA PET study using 2 methods of analysis

Author: Bouilleret, Viviane, Semah, Franck, Biraben, Arnaud, Taussig, Delphine, Chassoux, Francine, Syrota, André, Ribeiro, Maria-João, Quentin, Aurore, Service Hospitalier Frédéric Joliot (SHFJ), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service de neurophysiologie clinique et d'épileptologie, Université Paris-Sud - Paris 11 (UP11)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Bicêtre, Service de neurologie [Rennes], Université de Rennes (UR), Service de Neurochirurgie, and Hôpital Saint-Anne
Subjects: [SDV.IB] Life Sciences [q-bio]/Bioengineering, MESH: Middle Aged, MESH: Humans, MESH: Adult, MESH: Algorithms, MESH: Dihydroxyphenylalanine, MESH: Male, MESH: Positron-Emission Tomography, MESH: Basal Ganglia, MESH: Anticonvulsants, MESH: Epilepsy, MESH: Reproduc, MESH: Drug Resistance, [SDV.IB]Life Sciences [q-bio]/Bioengineering, MESH: Image Interpretation, Computer-Assisted, MESH: Female, MESH: Radiopharmaceuticals, MESH: Brain Mapping
Abstract: Studies in animal models and epileptic patients have led to the suggestion that the basal ganglia (BG) are involved in seizures. PET with 6-18F-L-3,4-fluorodihydroxyphenylalanine (18F-fluoro-L-DOPA) has recently demonstrated a reduction of striatal dopamine uptake in drug-resistant epileptic patients with ring chromosome 20 (r20) using a multiple-time graphical analysis. The aim of the present study was to evaluate the involvement of dopamine in other epileptic syndromes using a multiple-time graphical analysis and the all-brain statistical parametric mapping (SPM) analysis. METHODS: Patients with drug-resistant epilepsy were divided into 3 groups: group 1, with r20 epilepsy (n = 16; mean age +/- SD, 21.5 +/- 5.4 y); group 2, with resistant generalized "absence-like" epilepsy (n = 10; mean age, 32.3 +/- 11.4 y); and group 3, with drug-resistant temporal lobe epilepsy with hippocampal sclerosis (n = 9; mean age, 35.2 +/- 10.3 y). We compared 2 strategies of analysis of the 18F-fluoro-L-DOPA uptake constant (K(i), min(-1)) in BG using a multiple-time graphical analysis using regions of interest (the gold-standard method) and an SPM analysis using a voxel-by-voxel statistical t test to avoid a priori hypotheses in the analysis. Each epileptic group was compared with a group of healthy volunteers (n = 10; mean age, 45.1 +/- 16.5 y). RESULTS: A decrease of the mean K(i) value was observed in the striatum in all groups of patients with both types of analysis. With multiple-time graphical analysis, the reduction was evident using the averaged K(i) values over both hemispheres in each BG. Unilateral decreases in each BG were detected in SPM analysis. A ratio of decrease of 18F-fluoro-L-DOPA uptake was observed in the 3 groups of patients. Only the SPM analysis showed a decrease of 18F-fluoro-L-DOPA uptake ipsilateral to the seizure side in patients with temporal lobe epilepsy. Moreover, the all-brain SPM analysis showed a decrease of 18F-fluoro-L-DOPA uptake in the substantia nigra bilaterally (P < 0.001). CONCLUSION: This result confirms the involvement of dopamine neurotransmission in seizure control related to the type of epileptic syndrome. The difference in epileptic types may depend in part on the seizure frequency.
Published: 2005

186. Direct evidence for a parietal-frontal pathway subserving spatial awareness in humans

Author: Richard Levy, Bruno Dubois, Emmanuelle Volle, Hugues Duffau, Marika Urbanski, Michel Thiebaut de Schotten, Paolo Bartolomeo, Bartolomeo, Paolo, Neuro-anatomie fonctionnelle du comportement et de ses troubles, Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR70-Institut National de la Santé et de la Recherche Médicale (INSERM), and Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR70-Université Pierre et Marie Curie - Paris 6 (UPMC)
Subjects: Male, MESH: Awareness, Settore M-PSI/02 - PSICOBIOLOGIA E PSICOLOGIA FISIOLOGICA, Stimulation, MESH: Frontal Lobe, Brain mapping, MESH: Glioma, Superior temporal gyrus, 0302 clinical medicine, Parietal Lobe, Neural Pathways, MESH: Brain Mapping, MESH: Parietal Lobe, Brain Mapping, Multidisciplinary, Brain Neoplasms, 05 social sciences, Parietal lobe, MESH: Electric Stimulation, Glioma, Awareness, Temporal Lobe, Frontal Lobe, Frontal lobe, MESH: Brain Neoplasms, Female, Electrical brain stimulation, Adult, MESH: Space Perception, Posterior parietal cortex, Biology, 050105 experimental psychology, Temporal lobe, Perceptual Disorders, 03 medical and health sciences, [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology, MESH: Temporal Lobe, Humans, 0501 psychology and cognitive sciences, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, MESH: Perceptual Disorders, MESH: Humans, MESH: Neural Pathways, MESH: Adult, MESH: Male, Electric Stimulation, MESH: Nerve Net, MESH: Brain Ne, Space Perception, Nerve Net, Neuroscience, MESH: Female, 030217 neurology & neurosurgery
Abstract: Intraoperative electrical stimulation, which temporarily inactivates restricted regions during brain surgery, can map cognitive functions in humans with spatiotemporal resolution unmatched by other methods. Using this technique, we found that stimulation of the right inferior parietal lobule or the caudal superior temporal gyrus, but not of its rostral portion, determined rightward deviations on line bisection. However, the strongest shifts occurred with subcortical stimulation. Fiber tracking identified the stimulated site as a section of the superior occipitofrontal fasciculus, a poorly known parietal-frontal pathway. These findings suggest that parietal-frontal communication is necessary for the symmetrical processing of the visual scene.
Published: 2005
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187. A probabilistic functional atlas of the VIM nucleus constructed from pre-, intra- and postoperative electrophysiological and neuroimaging data acquired during the surgical treatment of Parkinson's disease patients

Author: A. Thirunavuukarasuu, Dmitry Belov, Alim-Louis Benabid, Wieslaw L. Nowinski, Biomedical Imaging Lab, Agency for Science, Technology and Research, Neurosciences précliniques, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Département de neurologie, Université Joseph Fourier - Grenoble 1 (UJF)-CHU Grenoble, and Issartel, Jean-Paul
Subjects: Parkinson's disease, Physics::Instrumentation and Detectors, Physics::Medical Physics, MESH: Stereotaxic Techniques, MESH: Algorithms, MESH: Imaging, Three-Dimensional, Brain mapping, 030218 nuclear medicine & medical imaging, Stereotaxic Techniques, Central nervous system disease, 03 medical and health sciences, Imaging, Three-Dimensional, 0302 clinical medicine, Degenerative disease, Thalamus, Neuroimaging, Humans, Medicine, MESH: Brain Mapping, Third Ventricle, MESH: Thalamus, Brain Mapping, MESH: Electrophysiology, MESH: Humans, Quantitative Biology::Neurons and Cognition, business.industry, Brain atlas, Probabilistic logic, Parkinson Disease, medicine.disease, Electrodes, Implanted, Electrophysiology, Radiography, Ventromedial Hypothalamic Nucleus, Stereotaxic technique, Surgery, MESH: Electrodes, Implanted, Neurology (clinical), business, Neuroscience, Algorithms, 030217 neurology & neurosurgery, MESH: Parkinson Disease, MESH: Third Ventricle, MESH: Ventromedial Hypothalamic Nucleus
Abstract: We have previously introduced a concept of a probabilistic functional atlas (PFA) to overcome limitations of the current electronic stereotactic brain atlases: anatomical nature, spatial sparseness, inconsistency and lack of population information. The PFA for the STN has already been developed. This work addresses construction of the PFA for the ventrointermediate nucleus (PFA-VIM). The PFA-VIM is constructed from pre-, intra- and postoperative electrophysiological and neuroimaging data acquired during the surgical treatment of Parkinson’s disease patients. The data contain the positions of the chronically implanted electrodes and their best contacts. For each patient, the intercommissural distance, height of the thalamus and width of the third ventricle were measured. An algorithm was developed to convert these data into the PFA-VIM, and to present them on axial, coronal and sagittal planes and in 3-D. The PFA-VIM gives a spatial distribution of the best contacts, and its probability is proportional to best contact concentration in a given location. The region with the highest probability corresponds to the best target. The PFA-VIM is calculated with 0.25-mm3 resolution from 107 best contacts in two situations: with and without lateral compensation against the width of the third ventricle. For the PFA-VIM compensated laterally, the anterior, lateral and dorsal coordinates of the mean value are (in mm) 6.24, 13.83, 1.68 for the left VIM and 6.54, –13.84, 2.10 for the right VIM. The coordinates of the mean value of the highest probability region along with the highest number of the best contacts (P) are: 6.25, 14.25, 1.75, P = 16, for the left VIM, and 6.0, –14.0, 1.00, P = 18, for the right VIM. The coordinate system origin is at the posterior commissure. For the PFA-VIM not compensated laterally, the coordinates of the mean value are 6.24, 13.99, 1.68 for the left VIM and 6.53, –14.13, 2.10 for the right VIM. The coordinates of the mean value of the highest probability region along with the highest number of the best contacts are 5.58, 13.67, 1.33, P = 14, for the left VIM, and 6.36, –14.03, 1.11, P = 17, for the right VIM. The PFA-VIM atlas overcomes several limitations of the current anatomical atlases and can improve targeting of thalamotomies and thalamic stimulations. It is dynamic and can easily be extended with new cases.
Published: 2005
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188. Distinct unimodal and multimodal regions for word processing in the left temporal cortex

Author: Denis Le Bihan, Stanislas Dehaene, Antoinette Jobert, Laurent D. Cohen, Institut de biologie et chimie des protéines [Lyon] (IBCP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Service de Neurologie [CHU Pitié-Salpêtrière], IFR70-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Institutions et Dynamiques Historiques de l'Economie (IDHE), École normale supérieure - Cachan (ENS Cachan)-Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris 8 Vincennes-Saint-Denis (UP8)-Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS), Service NEUROSPIN (NEUROSPIN), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Human Brain Research Center [Kyoto] (HBRC), Kyoto University [Kyoto], Service Hospitalier Frédéric Joliot (SHFJ), Neuroimagerie cognitive (LCogn), Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Santé et de la Recherche Médicale (INSERM), CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Kyoto University, Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Service de neurologie 1 [CHU Pitié-Salpétrière], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], and Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)
Subjects: Male, MESH: Mitral Valve Insufficiency, genetic structures, MESH: Echocardiography, Doppler, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Speech recognition, Word processing, MESH: Epidemiologic Methods, MESH: Semantics, MESH: Magnetic Resonance Imaging, MESH: Balloon Dilatation, 0302 clinical medicine, Image Processing, Computer-Assisted, Visual word form area, MESH: Brain Mapping, MESH: Treatment Outcome, Temporal cortex, Brain Mapping, 05 social sciences, Superior temporal sulcus, Magnetic Resonance Imaging, MESH: Image Processing, Computer-Assisted, Temporal Lobe, Semantics, Neurology, Pattern Recognition, Visual, Speech Perception, Female, Occipital Lobe, MESH: Image Enhancement, Psychology, psychological phenomena and processes, MESH: Oxygen, MESH: Occipital Lobe, Adult, MESH: Heart Valve Prosthesis, Cognitive Neuroscience, MESH: Phonetics, MESH: Pattern Recognition, Visual, MESH: Rheumatic Heart Disease, MESH: Imaging, Three-Dimensional, MESH: Reading, 050105 experimental psychology, Temporal lobe, 03 medical and health sciences, Stimulus modality, Imaging, Three-Dimensional, Phonetics, Humans, MESH: Temporal Lobe, 0501 psychology and cognitive sciences, Dominance, Cerebral, MESH: Humans, MESH: Adult, MESH: Speech Perception, MESH: Dominance, Cerebral, Image Enhancement, MESH: Male, Oxygen, Reading, MESH: Nerve Net, Word recognition, Nerve Net, Occipital lobe, MESH: Female, 030217 neurology & neurosurgery
Abstract: International audience; How are word recognition circuits organized in the left temporal lobe? We used functional magnetic resonance imaging (fMRI) to dissect cortical word-processing circuits using three diagnostic criteria: the capacity of an area (1) to respond to words in a single modality (visual or auditory) or in both modalities, (2) to modulate its response in a top-down manner as a function of the graphemic or phonemic emphasis of the task, and (3) to show repetition suppression in response to the conscious repetition of the target word within the same sensory modality or across different modalities. The results clarify the organization of visual and auditory word-processing streams. In particular, the visual word form area (VWFA) in the left occipitotemporal sulcus appears strictly as a visual unimodal area. It is, however, bordered by a second lateral inferotemporal area which is multimodal [lateral inferotemporal multimodal area (LIMA)]. Both areas might have been confounded in past work. Our results also suggest a possible homolog of the VWFA in the auditory stream, the auditory word form area, located in the left anterior superior temporal sulcus.
Published: 2004
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189. Retinotopic organization of visual mental images as revealed by functional magnetic resonance imaging

Author: Jean-François Mangin, Ferath Kherif, Jean-Baptiste Poline, Denis Le Bihan, Jessica Dubois, Guillaume Flandin, Stephen M. Kosslyn, Michel Denis, Isabelle Klein, Département de radiothérapie, CRLCC Val d'Aurelle - Paul Lamarque, Institut de recherche en cancérologie de Montpellier ( IRCM ), Université Montpellier 1 ( UM1 ) -CRLCC Val d'Aurelle - Paul Lamarque-Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Université de Montpellier ( UM ), Laboratoire de Neuroimagerie Assistée par Ordinateur ( LNAO ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Service Hospitalier Frédéric Joliot ( SHFJ ), Direction de Recherche Fondamentale (CEA) ( DRF (CEA) ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay, Center for Neuroscience and Behavioral Medicine, Children's National Medical Center, Service NEUROSPIN ( NEUROSPIN ), Institut de Génétique et Développement de Rennes ( IGDR ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -IFR140-Centre National de la Recherche Scientifique ( CNRS ), Biogéosciences [Dijon] ( BGS ), AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Université de Bourgogne ( UB ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d'Informatique pour la Mécanique et les Sciences de l'Ingénieur ( LIMSI ), Université Paris-Sud - Paris 11 ( UP11 ) -Centre National de la Recherche Scientifique ( CNRS ), Department of Psychology, Harvard University ( Department of Psychology, Harvard University ), Université de Lille, Sciences Humaines et Sociales, IFR de Neuroimagerie Fonctionnelle ( IFR 49 ), Human Brain Research Center [Kyoto] ( HBRC ), Kyoto University [Kyoto], Service Hospitalier Frédéric Joliot (SHFJ), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'Informatique pour la Mécanique et les Sciences de l'Ingénieur (LIMSI), Université Paris-Sud - Paris 11 (UP11)-Sorbonne Université - UFR d'Ingénierie (UFR 919), Sorbonne Université (SU)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Saclay (COmUE), Harvard University, Massachusetts General Hospital [Boston], Institut de recherche en cancérologie de Montpellier (IRCM - U896 Inserm - UM1), Université Montpellier 1 (UM1)-CRLCC Val d'Aurelle - Paul Lamarque-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM), Laboratoire de Neuroimagerie Assistée par Ordinateur (LNAO), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Service NEUROSPIN (NEUROSPIN), Institut de Génétique et Développement de Rennes (IGDR), Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Biogéosciences [UMR 6282] [Dijon] (BGS), Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), Department of Psychology, Harvard University (Department of Psychology, Harvard University), Harvard University [Cambridge], IFR de Neuroimagerie Fonctionnelle (IFR 49), Human Brain Research Center [Kyoto] (HBRC), and Le Bihan, Denis
Subjects: Male, Visual perception, MESH : Oxygen, genetic structures, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, MESH : Brain Mapping, MESH : Photic Stimulation, Mental imagery, MESH: Magnetic Resonance Imaging, Behavioral Neuroscience, 0302 clinical medicine, Mental Processes, Cluster Analysis, MESH : Female, Evoked Potentials, MESH: Mental Processes, MESH: Brain Mapping, [ SDV.IB.IMA ] Life Sciences [q-bio]/Bioengineering/Imaging, Brain Mapping, medicine.diagnostic_test, 05 social sciences, fMRI, Retinotopy, MESH : Adult, Magnetic Resonance Imaging, Visual field, MESH: Evoked Potentials, medicine.anatomical_structure, MESH: Photic Stimulation, Imagination, Visual Perception, Female, Psychology, MESH : Visual Perception, MESH: Oxygen, Mental image, MESH : Orientation, Adult, MESH : Imagination, Cognitive Neuroscience, MESH : Mental Processes, MESH : Male, MESH: Acoustic Stimulation, MESH: Orientation, Experimental and Cognitive Psychology, Sensory system, MESH : Visual Cortex, 050105 experimental psychology, 03 medical and health sciences, Neuroimaging, MESH : Visual Pathways, Orientation, MESH : Magnetic Resonance Imaging, medicine, Humans, MESH : Cluster Analysis, 0501 psychology and cognitive sciences, Visual Pathways, Visual cortex, MESH: Imagination, MESH: Visual Pathways, MESH: Humans, MESH: Visual Perception, MESH : Evoked Potentials, MESH : Humans, MESH: Visual Cortex, MESH: Adult, MESH : Acoustic Stimulation, MESH: Cluster Analysis, MESH: Male, Oxygen, [SDV.IB.IMA] Life Sciences [q-bio]/Bioengineering/Imaging, Acoustic Stimulation, Functional magnetic resonance imaging, Neuroscience, MESH: Female, 030217 neurology & neurosurgery, Photic Stimulation
Abstract: International audience; In this study, we used event-related functional magnetic resonance imaging to investigate whether visual mental images retinotopically activate early visual cortex. Six participants were instructed to visualize or view horizontally or vertically oriented flashing bow-tie shaped stimuli. When compared to baseline, imagery globally activated Area V1. When the activation evoked by the stimuli at the different orientations was directly compared, distinct spatial activation patterns were obtained for each orientation in most participants. Not only was the topography of the activation patterns from imagery similar to the topography obtained with a corresponding visual perception task, but it closely matched the individual cortical representation of either the horizontal or the vertical visual field meridians. These findings strongly support that visual imagery and perception share low-level anatomical substrate and functional processes. Binding of spatial features is suggested as one possible mechanism.
Published: 2004
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190. Learning-dependent activation of Fra-1: involvement of ventral hippocampus and SNc/VTA complex in learning and habit formation

Author: Françoise Condé, Alexis Faure, Fabrice Cheruel, Nicole El Massioui, Neurobiologie de l'apprentissage, de la mémoire et de la communication (NAMC), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Maladies Neurodégénératives - UMR 9199 (LMN), Service MIRCEN (MIRCEN), Institut de Biologie François JACOB (JACOB), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Biologie François JACOB (JACOB), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Biologie François JACOB (JACOB), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Biologie François JACOB (JACOB), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: MESH: Hippocampus, MESH: Rats, [SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology, education, MESH: Neurons, MESH: Conditioning, Operant, Hippocampus, MESH: Rats, Sprague-Dawley, Rats, Sprague-Dawley, 03 medical and health sciences, Habits, 0302 clinical medicine, mental disorders, medicine, Animals, Learning, MESH: Animals, MESH: Habits, Genes, Immediate-Early, MESH: Brain Mapping, MESH: Genes, Immediate-Early, 030304 developmental biology, Neurons, 0303 health sciences, Brain Mapping, [SDV.NEU.PC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Psychology and behavior, MESH: Proto-Oncogene Proteins c-fos, Overtraining, musculoskeletal, neural, and ocular physiology, [SCCO.NEUR]Cognitive science/Neuroscience, General Neuroscience, Dopaminergic, [SDV.NEU.SC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Cognitive Sciences, medicine.disease, MESH: Gene Expression Regulation, Rats, MESH: Models, Animal, nervous system, Gene Expression Regulation, Models, Animal, Conditioning, Operant, MESH: Learning, Psychology, Neuroscience, Immediate early gene, Proto-Oncogene Proteins c-fos, psychological phenomena and processes, 030217 neurology & neurosurgery
Abstract: International audience; Although the effect of overtraining on learning processes in rats has long been studied, only few studies have specifically assessed the differential involvement of brain areas in habit formation. We used the analysis of expression of the immediate early gene Fra-1 as a tool to differentiate the areas involved in training and overtraining. Behavioural experiments showed that instrumental performance (signalled and non-signalled instrumental tasks), but not pavlovian conditioned responses, were no longer under the control of the incentive value of the reward after overtraining. The number of Fra-1 expressing neurons was increased in SNc/VTA and ventral hippocampus after training in all groups independently of behavioural performance. After overtraining, the number of learning-induced Fra-1 immunoreactive neurons remained increased in the SNc/VTA. However, in CA1, it significantly decreased in the signalled instrumental group, whereas it further increased in the pavlovian group, with no modulation in non-signalled instrumental animals. The increase in the number of Fra-1 neurons observed after training in SNc/VTA and ventral hippocampus suggests that a general underlying incentive process regulates Fra-1. Moreover, the sustained increased expression of Fra-1 in the SNc/VTA after instrumental overtraining could reflect a possible role of dopaminergic neurons in habit formation.
Published: 2004
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191. Tuning curves for approximate numerosity in the human intraparietal sulcus

Author: Denis Le Bihan, Manuela Piazza, Véronique Izard, Stanislas Dehaene, Philippe Pinel, Departement of Psychology, Harvard University, Neuroimagerie cognitive (LCogn), Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Toulousain de Technologie et d'Ingénierie des Systèmes (LATTIS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-IUT Toulouse 2 Blagnac, Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT), Service NEUROSPIN (NEUROSPIN), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Human Brain Research Center [Kyoto] (HBRC), Kyoto University, Service Hospitalier Frédéric Joliot (SHFJ), Harvard University [Cambridge], Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J)-IUT Toulouse 2 Blagnac, Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse - Jean Jaurès (UT2J), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and Kyoto University [Kyoto]
Subjects: Adult, Computer science, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Neuroscience(all), Subitizing, Numerical cognition, Intraparietal sulcus, Choice Behavior, Macaque, MESH: Choice Behavior, Functional Laterality, 050105 experimental psychology, MESH: Semantics, MESH: Magnetic Resonance Imaging, MESH: Psychophysics, 03 medical and health sciences, 0302 clinical medicine, Parietal Lobe, biology.animal, Psychophysics, Humans, Approximate number system, 0501 psychology and cognitive sciences, MESH: Functional Laterality, Size Perception, MESH: Brain Mapping, Cerebral Cortex, Brain Mapping, MESH: Parietal Lobe, MESH: Humans, biology, MESH: Visual Perception, General Neuroscience, 05 social sciences, Numerosity adaptation effect, MESH: Adult, Magnetic Resonance Imaging, MESH: Cerebral Cortex, Semantics, Oxygen, MESH: Size Perception, MESH: Photic Stimulation, Visual Perception, Neural coding, Neuroscience, Photic Stimulation, 030217 neurology & neurosurgery, MESH: Oxygen
Abstract: International audience; Number, like color or movement, is a basic property of the environment. Recently, single neurons tuned to number have been observed in animals. We used both psychophysics and neuroimaging to examine whether a similar neural coding scheme is present in humans. When participants viewed sets of items with a variable number, the bilateral intraparietal sulci responded selectively to number change. Functionally, the shape of this response indicates that humans, like other animal species, encode approximate number on a compressed internal scale. Anatomically, the intraparietal site coding for number in humans is compatible with that observed in macaque monkeys. Our results therefore suggest an evolutionary basis for human elementary arithmetic.
Published: 2004
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192. Estimation of the hemodynamic response in event-related functional MRI: Bayesian networks as a framework for efficient Bayesian modeling and inference

Author: Guillaume Marrelec, Philippe Ciuciu, Mélanie Pélégrini-Issac, Habib Benali, Laboratoire d'Imagerie Fonctionnelle (LIF), Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR14-IFR49-Institut National de la Santé et de la Recherche Médicale (INSERM), UNF, MIC, Université de Montréal (UdeM), Service Hospitalier Frédéric Joliot (SHFJ), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Neuroimagerie Assistée par Ordinateur (LNAO), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut d'imagerie neurofonctionnelle (IIN), Institut National de la Santé et de la Recherche Médicale (INSERM)-Ecole Nationale Supérieure des Télécommunications (ENST)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École des hautes études en sciences sociales (EHESS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Imagerie médicale et quantitative, Institut National de la Santé et de la Recherche Médicale (INSERM), Post-doc CEA, Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-École des hautes études en sciences sociales (EHESS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Ecole Nationale Supérieure des Télécommunications (ENST)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), and Ciuciu, Philippe
Subjects: MESH: Models, Cardiovascular, Computer science, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Inference, MESH: Cognition, computer.software_genre, 030218 nuclear medicine & medical imaging, MESH: Magnetic Resonance Imaging, Bayes' theorem, 0302 clinical medicine, Cognition, Graphical model, Evoked Potentials, MESH: Brain Mapping, Brain Mapping, Radiological and Ultrasound Technology, Estimation theory, Models, Cardiovascular, Brain, MESH: Cerebrovascular Circulation, Magnetic Resonance Imaging, Computer Science Applications, MESH: Reproducibility of Results, MESH: Evoked Potentials, Cerebrovascular Circulation, Algorithm, Algorithms, Adult, Adolescent, MESH: Bayes Theorem, Posterior probability, Bayesian probability, Models, Neurological, MESH: Algorithms, Machine learning, Bayesian inference, Sensitivity and Specificity, 03 medical and health sciences, MESH: Brain, MESH: Computer Simulation, MESH: Models, Neurological, Image Interpretation, Computer-Assisted, Humans, Computer Simulation, Electrical and Electronic Engineering, MESH: Adolescent, MESH: Humans, Models, Statistical, Quantitative Biology::Neurons and Cognition, business.industry, Bayesian network, Reproducibility of Results, MESH: Adult, Bayes Theorem, MESH: Sensitivity and Specificity, [SDV.IB.IMA] Life Sciences [q-bio]/Bioengineering/Imaging, Artificial intelligence, business, computer, MESH: Image Interpretation, Computer-Assisted, 030217 neurology & neurosurgery, Software, MESH: Models, Statistical
Abstract: International audience; A convenient way to analyze blood-oxygen-level-dependent functional magnetic resonance imaging data consists of modeling the whole brain as a stationary, linear system characterized by its transfer function: the hemodynamic response function (HRF). HRF estimation, though of the greatest interest, is still under investigation, for the problem is ill-conditioned. In this paper, we recall the most general Bayesian model for HRF estimation and show how it can beneficially be translated in terms of Bayesian graphical models, leading to 1) a clear and efficient representation of all structural and functional relationships entailed by the model, and 2) a straightforward numerical scheme to approximate the joint posterior distribution, allowing for estimation of the HRF, as well as all other model parameters. We finally apply this novel technique on both simulations and real data.
Published: 2004
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193. Statistical shape modeling of low level visual area borders

Author: Isabelle Corouge, Michel Dojat, Christian Barillot, Vision, Action et Gestion d'informations en Santé (VisAGeS), Institut National de la Santé et de la Recherche Médicale (INSERM)-Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-SIGNAUX ET IMAGES NUMÉRIQUES, ROBOTIQUE (IRISA-D5), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-Télécom Bretagne-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-Télécom Bretagne-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Télécom Bretagne-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Neuroimagerie Fonctionnelle et Metabolique, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Dojat, Michel, Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-Télécom Bretagne-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-Télécom Bretagne-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Télécom Bretagne-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)
Subjects: Male, Computer science, [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, MESH: Magnetic Resonance Imaging, 0302 clinical medicine, Image Processing, Computer-Assisted, Computer vision, MESH: Brain Mapping, Visual Cortex, Brain Mapping, Radiological and Ultrasound Technology, 05 social sciences, Magnetic Resonance Imaging, Computer Graphics and Computer-Aided Design, MESH: Image Processing, Computer-Assisted, Visual field, medicine.anatomical_structure, Principal component analysis, Female, [SDV.IB]Life Sciences [q-bio]/Bioengineering, Computer Vision and Pattern Recognition, Algorithms, Adult, Health Informatics, MESH: Algorithms, External Data Representation, 050105 experimental psychology, 03 medical and health sciences, medicine, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, Humans, 0501 psychology and cognitive sciences, Radiology, Nuclear Medicine and imaging, Representation (mathematics), [SDV.IB] Life Sciences [q-bio]/Bioengineering, Models, Statistical, Landmark, MESH: Humans, business.industry, MESH: Visual Cortex, Statistical model, Pattern recognition, MESH: Adult, MESH: Male, Visual cortex, Retinotopy, Artificial intelligence, business, MESH: Female, 030217 neurology & neurosurgery, MESH: Models, Statistical
Abstract: International audience; This paper proposes a statistical modeling of functional landmarks delimiting low level visual areas which are highly variable across individuals. Low level visual areas are first precisely delineated by fMRI retinotopic mapping which provides detailed information about the correspondence between the visual field and its cortical representation. The model is then built by learning the variability within a given training set. It relies on an appropriate data representation and on the definition of an intrinsic coordinate system common to all visual maps. This allows to build a consistent training set on which a principal component analysis is eventually applied. Our approach constitutes a first step toward a functional landmark-based probabilistic atlas of low level visual areas.
Published: 2004
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194. Motor execution and imagination networks in post-stroke dystonia

Author: Stéphane Lehéricy, Denis Le Bihan, Sabine Meunier, Marie Vidailhet, Emmanuel Gerardin, Pierre-Francois Van de Moortele, Jean-Baptiste Poline, CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Neuro-anatomie fonctionnelle du comportement et de ses troubles, Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR70-Institut National de la Santé et de la Recherche Médicale (INSERM), Center for NeuroImaging Research-Human MRI Neuroimaging core facility for clinical research [ICM Paris] (CENIR), Institut du Cerveau = Paris Brain Institute (ICM), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut Européen des membranes (IEM), Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Service NEUROSPIN (NEUROSPIN), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Physiologie et physiopathologie de la motricité chez l'homme, CHU Saint-Antoine [AP-HP], Neurologie et thérapeutique expérimentale, Service de Neuroradiologie [CHU Pitié-Salpêtrière], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Centre de Neuro-Imagerie de Recherche (CENIR), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Service de neurologie [Saint-Antoine], Université Pierre et Marie Curie - Paris 6 (UPMC)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Saint-Antoine [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR70-Université Pierre et Marie Curie - Paris 6 (UPMC), Service de neurologie 1 [CHU Pitié-Salpétrière], IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service Hospitalier Frédéric Joliot (SHFJ), National Institutes of Health [Bethesda] (NIH), Human Brain Research Center [Kyoto] (HBRC), Kyoto University, Service de Neurologie [CHU Pitié-Salpêtrière], IFR70-CHU Pitié-Salpêtrière [AP-HP], Kyoto University [Kyoto], and Le Bihan, Denis
Subjects: Male, MESH: Dystonia, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Precuneus, Functional Laterality, MESH: Magnetic Resonance Imaging, 0302 clinical medicine, Basal ganglia, Prefrontal cortex, ComputingMilieux_MISCELLANEOUS, Problem Solving, MESH: Brain Mapping, Dystonia, MESH: Aged, Brain Mapping, 0303 health sciences, MESH: Middle Aged, medicine.diagnostic_test, General Neuroscience, Middle Aged, Magnetic Resonance Imaging, MESH: Case-Control Studies, MESH: Motor Activity, Stroke, medicine.anatomical_structure, Motor Skills, Imagination, Female, psychological phenomena and processes, MESH: Oxygen, Motor cortex, MESH: Problem Solving, Adult, Motor Activity, behavioral disciplines and activities, MESH: Stroke, MESH: Hand, Premotor cortex, 03 medical and health sciences, medicine, Humans, MESH: Functional Laterality, MESH: Imagination, Aged, 030304 developmental biology, MESH: Humans, [SDV.BA.MVSA]Life Sciences [q-bio]/Animal biology/Veterinary medicine and animal Health, business.industry, MESH: Adult, Hand, medicine.disease, MESH: Male, Oxygen, [SDV.IB.IMA] Life Sciences [q-bio]/Bioengineering/Imaging, nervous system, Case-Control Studies, business, Functional magnetic resonance imaging, Insula, Neuroscience, MESH: Female, 030217 neurology & neurosurgery, MESH: Motor Skills
Abstract: International audience; Reorganization of motor execution and imagination networks was studied in six patients with unilateral dystonia secondary to a subcortical stroke and compared with seven control subjects using fMRI. Patients performed imagined and real auditory-cued hand movements. Movements of the dystonic hand resulted in overactivity in bilateral motor, premotor, and prefrontal cortex, insula, precuneus, and cerebellum, in parietal areas and the striatum contralateral to the lesion. Movements of the unaffected hand resulted in overactivity in bilateral preSMA, prefrontal, and parietal areas, insula and cerebellum, the ipsilateral premotor cortex and the contralateral striatum to the lesion. Mental representation of movements with each hand resulted in overactivity in bilateral parietal, premotor and prefrontal areas. These results suggest that execution and mental representation of movement are altered in these patients.
Published: 2004
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195. Foot, face and hand representation in the human supplementary motor area

Author: Denis Le Bihan, Marie-Laure Tanguy, Stéphane Lehéricy, Emmanuel Gerardin, Alexandre Krainik, Hanna Chainay, Grenoble Institut des Neurosciences (GIN), Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Département de neuro-radiologie, Université Joseph Fourier - Grenoble 1 (UJF)-CHU Grenoble, Departement de neuroradiologie, CHU La Tronche, Service greffe de moelle osseuse, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Université Paris Diderot - Paris 7 (UPD7)-Groupe Hospitalier Saint Louis - Lariboisière - Fernand Widal [Paris], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Laboratoire d'Informatique, de Traitement de l'Information et des Systèmes (LITIS), Université Le Havre Normandie (ULH), Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA), Institut Européen des membranes (IEM), Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Service NEUROSPIN (NEUROSPIN), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Human Brain Research Center [Kyoto] (HBRC), Kyoto University, Service Hospitalier Frédéric Joliot (SHFJ), Center for NeuroImaging Research-Human MRI Neuroimaging core facility for clinical research [ICM Paris] (CENIR), Institut du Cerveau = Paris Brain Institute (ICM), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Neuro-anatomie fonctionnelle du comportement et de ses troubles, Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR70-Institut National de la Santé et de la Recherche Médicale (INSERM), CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Université Paris Diderot - Paris 7 (UPD7)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Groupe Hospitalier Saint Louis - Lariboisière - Fernand Widal [Paris], Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Kyoto University [Kyoto], Centre de Neuro-Imagerie de Recherche (CENIR), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Service de Neuroradiologie [CHU Pitié-Salpêtrière], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Grenoble-Université Joseph Fourier - Grenoble 1 (UJF), Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-Université Paris Diderot - Paris 7 (UPD7)-Groupe Hospitalier Saint Louis - Lariboisière - Fernand Widal [Paris], Assistance publique - Hôpitaux de Paris (AP-HP) (APHP), Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS), Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-CHU Pitié-Salpêtrière [APHP], Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR70-Université Pierre et Marie Curie - Paris 6 (UPMC), and Service de neuro-radiologie [CHU Pitié-Salpêtrière]
Subjects: Male, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, MESH: Frontal Lobe, MESH: Movement, Functional Laterality, MESH: Magnetic Resonance Imaging, 0302 clinical medicine, MESH: Brain Mapping, Foot (prosody), MESH: Aged, Brain Mapping, MESH: Middle Aged, Supplementary motor area, General Neuroscience, 05 social sciences, Representation (systemics), Paracentral sulcus, Anatomy, Middle Aged, SMA, Magnetic Resonance Imaging, Frontal Lobe, medicine.anatomical_structure, Frontal lobe, Female, MESH: Face, Surgical ablation, Adult, Movement, MESH: Psychomotor Performance, 050105 experimental psychology, MESH: Foot, MESH: Hand, 03 medical and health sciences, medicine, Humans, 0501 psychology and cognitive sciences, MESH: Functional Laterality, Aged, MESH: Humans, business.industry, Foot, MESH: Adult, Hand, MESH: Male, Face (geometry), Face, business, MESH: Female, 030217 neurology & neurosurgery, Psychomotor Performance
Abstract: International audience; The ability to localize the limb representation in the supplementary motor area (SMA) would be useful in planning surgical ablation of medial frontal lobe tumours. We investigated the relationship between the anatomy of the SMA and the functional representation of fingers, toes, and lips using fMRI in healthy volunteers. There was a significant difference between the location of the different body parts in the SMA, with a rostro-caudal location of the face, hand and foot areas. Limb representation was located in an area spanning < 1 cm rostral and 1 cm caudal to the paracentral sulcus. These results support the somatotopic organization of the human SMA and suggest that the paracentral sulcus represents a landmark for body representation.
Published: 2004
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196. Sequence of pattern onset responses in the human visual areas: an fMRI constrained VEP source analysis

Author: Simo Vanni, Jean Bullier, Michel Dojat, Christoph Segebarth, Jan Warnking, Chantal Delon-Martin, Centre de recherche cerveau et cognition (CERCO), Institut des sciences du cerveau de Toulouse. (ISCT), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Neuroimagerie Fonctionnelle et Metabolique, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Dojat, Michel
Subjects: Male, MESH: Evoked Potentials, Visual, Individuality, Visual evoked potentials, MESH: Magnetic Resonance Imaging, 0302 clinical medicine, Cortex (anatomy), Computer vision, Evoked potential, MESH: Brain Mapping, MESH: Individuality, Visual Cortex, Brain Mapping, MESH: Middle Aged, medicine.diagnostic_test, Orientation (computer vision), MESH: Retina, 05 social sciences, Electroencephalography, Middle Aged, Magnetic Resonance Imaging, medicine.anatomical_structure, MESH: Photic Stimulation, Neurology, Female, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Occipital Lobe, Psychology, MESH: Occipital Lobe, Adult, Visual N1, Cognitive Neuroscience, Models, Neurological, Retina, 050105 experimental psychology, 03 medical and health sciences, MESH: Models, Neurological, MESH: Electroencephalography, medicine, Humans, Visual Pathways, 0501 psychology and cognitive sciences, [SDV.NEU] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Latency (engineering), MESH: Visual Pathways, MESH: Humans, business.industry, MESH: Visual Cortex, MESH: Adult, MESH: Male, Visual cortex, Evoked Potentials, Visual, Artificial intelligence, Visual Fields, MESH: Visual Fields, Functional magnetic resonance imaging, business, Neuroscience, MESH: Female, Photic Stimulation, 030217 neurology & neurosurgery
Abstract: International audience; We measured the timing of activity in distinct functional areas of the human visual cortex after onset of a visual pattern. This is not possible with visual evoked potentials (VEPs) or magnetic fields alone, and direct combination of functional magnetic resonance imaging (fMRI) with electromagnetic data has turned out to be difficult. We tested a relatively new approach, where both position and orientation of the active cortex was given to the VEP source model. Subjects saw the same visual patterns flashed ON and OFF, both when recording VEPs and fMRI responses. We identified the positions and orientations of the activated cortex in four retinotopic areas in each individual, and the corresponding dipoles were seeded to model the individual evoked potential data. Unexplained variance, comprising signals from other areas, was inversely modeled. Despite the partially a priori fixed model and optimized signal-to-noise ratio of VEP data, full separation of retinotopic areas was only seldom possible due to crosstalk between the adjacent sources, but separation was usually possible between areas V1 and V3/V3a. Whereas the latencies generally followed the hierarchical organization of cortical areas (V1-V2-V3), with around 25 ms between the strongest responses, an early activation emerged 10-20 ms after V1, close to the temporo-occipital junction (LO/V5) and with an additional 20-ms latency in the corresponding region of the opposite hemisphere. Our approach shows that it is feasible to directly seed information from fMRI to electromagnetic source models and to identify the components and dynamics of VEPs in different retinotopic areas of a human individual.
Published: 2004
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197. Timing of interactions across the visual field in the human cortex

Author: Michel Dojat, Chantal Delon-Martin, Jean Bullier, Simo Vanni, Jan Warnking, Christoph Segebarth, Centre de recherche cerveau et cognition (CERCO), Institut des sciences du cerveau de Toulouse. (ISCT), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Neuroimagerie Fonctionnelle et Metabolique, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Dojat, Michel
Subjects: Male, MESH: Evoked Potentials, Visual, genetic structures, Individuality, Motion Perception, Visual system, Functional Laterality, MESH: Magnetic Resonance Imaging, 0302 clinical medicine, Cortex (anatomy), MESH: Brain Mapping, MESH: Individuality, Visual Cortex, Brain Mapping, MESH: Middle Aged, medicine.diagnostic_test, MESH: Retina, 05 social sciences, Middle Aged, Magnetic Resonance Imaging, P200, Visual field, medicine.anatomical_structure, MESH: Photic Stimulation, Neurology, MESH: Motion Perception, Human visual system model, Visual Perception, Female, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Psychology, Adult, Visual N1, Interaction, Cognitive Neuroscience, Models, Neurological, Retina, 050105 experimental psychology, 03 medical and health sciences, Human cortex, MESH: Models, Neurological, medicine, Humans, 0501 psychology and cognitive sciences, [SDV.NEU] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], MESH: Functional Laterality, MESH: Humans, MESH: Visual Perception, MESH: Visual Cortex, MESH: Adult, eye diseases, MESH: Male, Evoked Potentials, Visual, Visual Fields, MESH: Visual Fields, Functional magnetic resonance imaging, Neuroscience, N2pc, MESH: Female, Photic Stimulation, 030217 neurology & neurosurgery
Abstract: International audience; While it is generally believed that interactions across long distances in the visual field occur only in the higher-order cortical areas, other results suggest that such interactions are processed very early. In the preceding paper, we identified the latencies within a subset of cortical areas in the human visual system. In the present study, we test in which areas and at which latencies the responses to two visual patterns start interacting. We used functional magnetic resonance imaging directly combined with visual-evoked potential source analysis. Interactions appeared first anterolaterally to the retinotopic areas, at 80 ms for two stimuli presented in the left lower visual quadrant and at 100 ms for symmetrical stimulation of both lower quadrants. In the lateral occipital-V5 region (LOV5), two patterns presented simultaneously in one quadrant elicited a response with shorter latency and infra-linear addition of the amplitudes compared with the patterns presented separately. For bilateral stimulation, the timing of the LOV5 response coincided with the response to contralateral stimulation alone. Other visual areas showed interactions appearing later than within LOV5: starting at 150 ms in V1, at 120 ms in V3-V3a for the left visual hemifield stimulation and at 160 ms for both visual hemifields stimulation. Our data show that distinct patterns in the visual field interact first in LOV5, suggesting that this region must be the first to pool spatial information across the whole visual field.
Published: 2004
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198. Coordinate-based versus structural approaches to brain image analysis

Author: J.-F. Mangin, D. Le Bihan, Jean Régis, Dimitri Papadopoulos-Orfanos, Y. Cointepas, C. Poupon, Jean-Baptiste Poline, D. Rivière, Arnaud Cachia, Olivier Coulon, Laboratoire de Neuroimagerie Assistée par Ordinateur (LNAO), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service Hospitalier Frédéric Joliot (SHFJ), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Center for Neuroscience and Behavioral Medicine, Children's National Medical Center, Génomique métabolique (UMR 8030), Genoscope - Centre national de séquençage [Evry] (GENOSCOPE), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université d'Évry-Val-d'Essonne (UEVE)-Centre National de la Recherche Scientifique (CNRS), Service d'exploration de la fonction respiratoire et de médecine du sport, Centre Hospitalier Universitaire de Toulouse (CHU Toulouse), Laboratoire d'Imagerie et de Spectroscopie (LRMN), Institut d'imagerie neurofonctionnelle (IIN), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-École des hautes études en sciences sociales (EHESS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Ecole Nationale Supérieure des Télécommunications (ENST)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Traitement et Communication de l'Information (LTCI), Télécom ParisTech-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS), Service NEUROSPIN (NEUROSPIN), IFR de Neuroimagerie Fonctionnelle (IFR 49), Human Brain Research Center [Kyoto] (HBRC), Kyoto University, Epilepsies, Lesions Cerebrales et Systemes Neuraux de la Cognition, Université de la Méditerranée - Aix-Marseille 2-Institut National de la Santé et de la Recherche Médicale (INSERM), Service de neurochirurgie [CHU Marseille], Université de la Méditerranée - Aix-Marseille 2-Assistance Publique - Hôpitaux de Marseille (APHM)- Hôpital de la Timone [CHU - APHM] (TIMONE), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, CHU Toulouse [Toulouse], Institut National de la Santé et de la Recherche Médicale (INSERM)-Ecole Nationale Supérieure des Télécommunications (ENST)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École des hautes études en sciences sociales (EHESS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Kyoto University [Kyoto], and Service de neurochirurgie
Subjects: Matching (statistics), Computer science, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Medicine (miscellaneous), Inference, Image processing, Machine learning, computer.software_genre, Models, Biological, Brain mapping, 030218 nuclear medicine & medical imaging, MESH: Magnetic Resonance Imaging, 03 medical and health sciences, MESH: Brain, 0302 clinical medicine, Neuroimaging, Artificial Intelligence, MESH: Markov Chains, Image Processing, Computer-Assisted, Humans, Set (psychology), MESH: Brain Mapping, Parametric statistics, Brain Mapping, MESH: Humans, business.industry, MESH: Models, Biological, Brain, Magnetic Resonance Imaging, MESH: Image Processing, Computer-Assisted, Markov Chains, Group analysis, Artificial intelligence, business, computer, 030217 neurology & neurosurgery
Abstract: International audience; A basic issue in neurosciences is to look for possible relationships between brain architecture and cognitive models. The lack of architectural information in magnetic resonance images, however, has led the neuroimaging community to develop brain mapping strategies based on various coordinate systems without accurate architectural content. Therefore, the relationships between architectural and functional brain organizations are difficult to study when analyzing neuroimaging experiments. This paper advocates that the design of new brain image analysis methods inspired by the structural strategies often used in computer vision may provide better ways to address these relationships. The key point underlying this new framework is the conversion of the raw images into structural representations before analysis. These representations are made up of data-driven elementary features like activated clusters, cortical folds or fiber bundles. Two classes of methods are introduced. Inference of structural models via matching across a set of individuals is described first. This inference problem is illustrated by the group analysis of functional statistical parametric maps (SPMs). Then, the matching of new individual data with a priori known structural models is described, using the recognition of the cortical sulci as a prototypical example.
Published: 2004
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199. [Identifying distinct components in the cerebral treatment of visual sexual information through functional neuroimaging]

Author: Harold, Mouras, Laboratoire de Neurosciences Fonctionnelles et Pathologies (LNFP), and Université de Lille, Droit et Santé-Centre National de la Recherche Scientifique (CNRS)
Subjects: Male, MESH: Sexual Behavior, Sexual Behavior, Emotions, Models, Neurological, MESH: Motivation, Hypothalamus, MESH: Cognition, Models, Psychological, Gyrus Cinguli, MESH: Magnetic Resonance Imaging, Cognition, MESH: Models, Neurological, MESH: Gyrus Cinguli, MESH: Plethysmography, Animals, Humans, MESH: Animals, MESH: Models, Psychological, MESH: Brain Mapping, MESH: Imagination, MESH: Emotions, Cerebral Cortex, Brain Mapping, Motivation, MESH: Humans, MESH: Visual Perception, Penile Erection, MESH: Arousal, MESH: Penile Erection, Magnetic Resonance Imaging, MESH: Hypothalamus, MESH: Male, MESH: Positron-Emission Tomography, MESH: Cerebral Cortex, Plethysmography, Positron-Emission Tomography, Imagination, Visual Perception, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Arousal
Abstract: International audience; For now several years, the growing developement of neuroimaging techniques such as Positron Emission Tomography (PET) or functional Magnetic Resonance Imaging (fMRI) allowed a better understanding of neural processes involved in human emotions and goal-directed behaviors. In particular, several studies are now available on the neural correlates of male sexual arousal. A neurobehavioral model of neural processes involved in sexual arousal has been proposed (Redout?t al., 2000) comprising: i) a cognitive component; ii) an emotional component; iii) a motivational component and iv) an autonomic component. Among other regions, several cerebral areas have been found to be linked to: 1) the cognitive component which comprises: i) the orbitofrontal cortex involved in attentional processes directed toward the target and the superior parietal lobules; ii) the inferior parietal lobules involved in motor imagery processes; 2) the motivational component which involves the caudal part of the anterior cingulate cortex, related to motor preparation processes; 3) the autonomic component: concurrent measures of cerebral activations by functional neuroimaging and of erectile response by penile plethysmography allow the demonstration of the involvement of the hypothalamus, the insula, and the rostral part of the anterior cingulate cortex in this component.
Published: 2004

200. Reference frames for spatial cognition: Different brain areas are involved in viewer-, object-, and landmark-centered judgments about object location

Author: Denis LeBihan, Anne-Lise Paradis, Giorgia Committeri, Luigi Pizzamiglio, Alain Berthoz, Gaspare Galati, Laboratoire de Physiologie de la Perception et de l'Action (LPPA), Collège de France (CdF (institution))-Centre National de la Recherche Scientifique (CNRS), Université du Québec à Montréal = University of Québec in Montréal (UQAM), Geometry and Probability for Motion and Action (E-MOTION), Laboratoire d'informatique GRAphique, VIsion et Robotique de Grenoble (GRAVIR - IMAG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG)-Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria), Service NEUROSPIN (NEUROSPIN), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service Hospitalier Frédéric Joliot (SHFJ), Human Brain Research Center [Kyoto] (HBRC), Kyoto University [Kyoto], National Institutes of Health [Bethesda] (NIH), Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Inria Grenoble - Rhône-Alpes, Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Kyoto University
Subjects: Male, genetic structures, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, MESH: Frontal Lobe, MESH: Magnetic Resonance Imaging, User-Computer Interface, 0302 clinical medicine, Discrimination, Psychological, Reference Values, Parietal Lobe, MESH: Discrimination (Psychology), MESH: Brain Mapping, Temporal cortex, Cerebral Cortex, Brain Mapping, MESH: Parietal Lobe, medicine.diagnostic_test, 05 social sciences, Parietal lobe, MESH: Reference Values, Magnetic Resonance Imaging, Temporal Lobe, Frontal Lobe, medicine.anatomical_structure, MESH: Photic Stimulation, Frontal lobe, Female, Occipital Lobe, MESH: Computer Graphics, Psychology, MESH: Occipital Lobe, Adult, Cognitive Neuroscience, MESH: Space Perception, Posterior parietal cortex, Spatial Behavior, 050105 experimental psychology, Premotor cortex, 03 medical and health sciences, Judgment, MESH: Computer Simulation, MESH: Spatial Behavior, medicine, Computer Graphics, Humans, MESH: Temporal Lobe, 0501 psychology and cognitive sciences, Computer Simulation, MESH: User-Computer Interface, MESH: Judgment, MESH: Humans, MESH: Adult, Spatial cognition, MESH: Male, MESH: Cerebral Cortex, Space Perception, Occipital lobe, Functional magnetic resonance imaging, Neuroscience, MESH: Female, 030217 neurology & neurosurgery, Photic Stimulation
Abstract: Functional magnetic resonance imaging was used to compare the neural correlates of three different types of spatial coding, which are implicated in crucial cognitive functions of our everyday life, such as visuomotor coordination and orientation in topographical space. By manipulating the requested spatial reference during a task of relative distance estimation, we directly compared viewer-centered, object-centered, and landmark-centered spatial coding of the same realistic 3-D information. Common activation was found in bilateral parietal, occipital, and right frontal premotor regions. The retrosplenial and ventromedial occipital–temporal cortex (and parts of the parietal and occipital cortex) were significantly more activated during the landmark-centered condition. The ventrolateral occipital–temporal cortex was particularly involved in object-centered coding. Results strongly demonstrate that viewer-centered (egocentric) coding is restricted to the dorsal stream and connected frontal regions, whereas a coding centered on external references requires both dorsal and ventral regions, depending on the reference being a movable object or a landmark.
Published: 2004
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