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International audience; Conversation represents a considerable amount of the daily language usage and plays an important role in language acquisition. In conversation, listeners simultaneously process their interlocutor's turn and prepare their own next turn. As such the turn-taking dynamics heavily relies on prediction. In other words, listeners avail prior knowledge to constrain both speech perception and production. Here we explored the relation between prediction and comprehension while watching two interlocutors having a conversation. We capitalize on gaze switch as a proxy of predictive behaviour to class dialogue turns as more or less well predicted and explore how this affects dialogue comprehension. Moreover, we study the extent to which speech degradation, by increasing the global uncertainty of the context, affects the relation between predictions, brain correlates of prediction errors (N400) and 2 global comprehension. Results show that 1) listeners direct gaze to the current speaker, in particular in challenging conditions, 2) gaze behaviour possibly affects the semantic processing of the upcoming turn (N400), 3) participants with a more efficient gaze predictive behaviour better solve semantic uncertainties at the turn onset, in particular in the most challenging listening condition. Our findings contribute to a better understanding of the relation between predictions, neural predictions errors and speech comprehension under challenging conditions.

IntroductionStrokes leave around 40% of survivors dependent in their activities of daily living, notably due to severe motor disabilities. Brain-computer interfaces (BCIs) have been shown to be efficiency for improving motor recovery after stroke, but this efficiency is still far from the level required to achieve the clinical breakthrough expected by both clinicians and patients. While technical levers of improvement have been identified (e.g., sensors and signal processing), fully optimized BCIs are pointless if patients and clinicians cannot or do not want to use them. We hypothesize that improving BCI acceptability will reduce patients' anxiety levels, while increasing their motivation and engagement in the procedure, thereby favoring learning, ultimately, and motor recovery. In other terms, acceptability could be used as a lever to improve BCI efficiency. Yet, studies on BCI based on acceptability/acceptance literature are missing. Thus, our goal was to model BCI acceptability in the context of motor rehabilitation after stroke, and to identify its determinants.MethodsThe main outcomes of this paper are the following: i) we designed the first model of acceptability of BCIs for motor rehabilitation after stroke, ii) we created a questionnaire to assess acceptability based on that model and distributed it on a sample representative of the general public in France (N = 753, this high response rate strengthens the reliability of our results), iii) we validated the structure of this model and iv) quantified the impact of the different factors on this population.ResultsResults show that BCIs are associated with high levels of acceptability in the context of motor rehabilitation after stroke and that the intention to use them in that context is mainly driven by the perceived usefulness of the system. In addition, providing people with clear information regarding BCI functioning and scientific relevance had a positive influence on acceptability factors and behavioral intention.DiscussionWith this paper we propose a basis (model) and a methodology that could be adapted in the future in order to study and compare the results obtained with: i) different stakeholders, i.e., patients and caregivers; ii) different populations of different cultures around the world; and iii) different targets, i.e., other clinical and non-clinical BCI applications.

Submitted to Magnetic Resonance in Medicine; Purpose: To evaluate the benefits of SPARKLING, a stochastic k-space sampling approach over the deterministic sampling scheme TPI (Twisted Projection Imaging) in the context of accelerated cerebral $^{23}$Na MRI and assessing its impact on tissue sodium concentration (TSC) estimation.Methods: Guided by simulation results, in vitro and in vitro UTE $^{23}$Na MRI datasets were acquired at a 4 mm isotropic resolution from healthy volunteers using both TPI or SPARKLING trajectories with different acceleration factors (AF) on a 7T MR scanner equipped with a 32 channels head coil. Following reconstruction using NUFFT or Proximal Optimized Gradient Method (POGM) algorithms with or without regularization, respectively, the resulting sodium images were compared in terms of effective resolution (FWHM of the PSF), SNR and overall quality. with an in vitro assement of the accuracy of the TSC was performed via external referencing using a 4-point calibration approach. Results: In vivo cerebral sodium images acquired using SPARKLING with an acceleration factor of 32 (TA= 5 min 38 s) are similar to those obtained using TPI at AF=8 (TA= 22 min 34 s) with minimal impact on the accuracy of our TSC quantification. Conclusion: In conditions compatible with clinical examination, undersampled SPARKLING $^{23}$Na MRI can outperform the conventional TPI k-space sampling scheme allowing for shorter acquisition times.

International audience; Learning to write music in the staff notation used in Western classical music is part of the musician’s training. However, writing music by hand is rarely taught formally, and many musicians are not aware of the characteristics of their musical handwriting. As with any symbolic expression, musical handwriting is related to the underlying cognition of the musical structures being depicted. Trained musicians read, think, and play music with high-level structures in mind. It seems natural that they would also write music by hand with these structures in mind. Moreover, improving our understanding of handwriting may help to improve both optical music recognition (OMR) and music notation and composition interfaces. We investigated associations between music training and experience and the way people write music by hand. We made video-recordings of participants’ hands while they were copying or freely writing music and analysed the sequence in which they wrote the elements contained in the musical score. The results confirmed that experienced musicians wrote faster than beginners, that they were more likely to write chords from bottom to top, and that they tended to write the note-heads first, in a flowing fashion, and only afterwards use stems and beams to emphasize grouping, and add expressive markings.

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International audience; Purpose: The aim of this study was to define the role of dystrophin Dp71 in corneal angiogenesis.Methods: Inflammation-induced corneal neovascularization experiments were performed in Dp71-null mice and C57BL/6J wild-type mice.Results: The corneal neovascular area covered by neovascularization was larger in the injured corneas of the Dp71-null mice compared to the corneas of the wild-type mice: 40.72% versus 26.33%, respectively (p

Analysis of grip force signals tailored to hand and finger movement evolution and changes in grip force control during task execution provide unprecedented functional insight into somatosensory cognition. Somatosensory cognition is the basis of our ability to act upon and to transform the physical world around us, to recognize objects on the basis of touch alone, and to grasp them with the right amount of force for lifting and manipulating them. Recent technology has permitted the wireless monitoring of grip force signals recorded from biosensors in the palm of the human hand to track and trace human grip forces deployed in cognitive tasks executed under conditions of variable sensory (visual, auditory) input. Non-invasive multi-finger grip force sensor technology can be exploited to explore functional interactions between somatosensory brain mechanisms and motor control, in particular during learning a cognitive task where the planning and strategic execution of hand movements is essential. Sensorial and cognitive processes underlying manual skills and/or hand-specific (dominant versus non-dominant hand) behaviors can be studied in a variety of contexts by probing selected measurement loci in the fingers and palm of the human hand. Thousands of sensor data recorded from multiple spatial locations can be approached statistically to breathe functional sense into the forces measured under specific task constraints. Grip force patterns in individual performance profiling may reveal the evolution of grip force control as a direct result of cognitive changes during task learning. Grip forces can be functionally mapped to from-global-to-local coding principles in brain networks governing somatosensory processes for motor control in cognitive tasks leading to a specific task expertise or skill. Under the light of a comprehensive overview of recent discoveries into the functional significance of human grip force variations, perspectives for future studies in cognition, in particular the cognitive control of strategic and task relevant hand movements in complex real-world precision task, are pointed out.

Neural activity in the sensory cortex combines stimulus responses and ongoing activity, but it remains unclear whether these reflect the same underlying dynamics or separate processes. In the present study, we show in mice that, during wakefulness, the neuronal assemblies evoked by sounds in the auditory cortex and thalamus are specific to the stimulus and distinct from the assemblies observed in ongoing activity. By contrast, under three different anesthetics, evoked assemblies are indistinguishable from ongoing assemblies in the cortex. However, they remain distinct in the thalamus. A strong remapping of sensory responses accompanies this dynamic state change produced by anesthesia. Together, these results show that the awake cortex engages dedicated neuronal assemblies in response to sensory inputs, which we suggest is a network correlate of sensory perception.

International audience; In uncertain environments, seeking information about alternative choice options is essential for adaptive learning and decision-making. However, information seeking is usually confounded with changes-of-mind about the reliability of the preferred option. Here, we exploited the fact that information seeking requires control over which option to sample to isolate its behavioral and neurophysiological signatures. We found that changes-of-mind occurring with control require more evidence against the current option, are associated with reduced confidence, but are nevertheless more likely to be confirmed on the next decision. Multimodal neurophysiological recordings showed that these changes-of-mind are preceded by stronger activation of the dorsal attention network in magnetoencephalography, and followed by increased pupil-linked arousal during the presentation of decision outcomes. Together, these findings indicate that information seeking increases the saliency of evidence perceived as the direct consequence of one’s own actions.

With its context-independent rules valid in any setting, mathematics is considered to be the champion of abstraction, and for a long time human mathematical reasoning was thought to follow nothing but the laws of logic. However, the idea that mathematics is grounded in nature has gained traction over the past decades, and the context-independency of mathematical reasoning has come to be questioned. The thesis we defend concerns the role played by general, non-mathematical knowledge on individuals' understanding of numerical situations. We propose that what we count has a crucial impact on how we count, in the sense that human's representation of numerical information is dependent on the semantic context in which it is embedded. More specifically, we argue that general, non-mathematical knowledge about the entities described in a mathematical word problem can shape its interpretation and foster one of two representations: either a cardinal encoding, or an ordinal encoding. After introducing a new framework of arithmetic word problem solving accounting for the interactions between mathematical knowledge and world knowledge in the encoding, recoding and solving of arithmetic word problems, we present a series of 16 experiments assessing how world knowledge about specific quantities can promote one of two problem representations. Using isomorphic arithmetic word problems involving either cardinal quantities (weights, prices, collections) or ordinal quantities (durations, heights, number of floors), we investigate the pervasiveness of the cardinal-ordinal distinction in a wide range of activities, including problem categorization, problem comparison, algorithm selection, problem solvability assessment, problem recall, sentence recognition, drawing production and transfer of strategies. We gather data using behavioral measures (success rates, algorithm use, response times) as well as eye tracking (fixation times, saccades, pupil dilation), to show that the difference between problems meant to foster either a cardinal or an ordinal encoding has a far-reaching influence on participants from diverse populations (N = 2180), ranging from 2nd graders and 5th graders to lay adults, expert mathematicians and math teachers. We discuss the general educational implications of these effects of semantic (in)congruence, and we propose new directions for future research on this crucial issue. We conclude that these findings illustrate the extent to which human reasoning is constrained by the content on which it operates, even in domains where abstraction is praised and trained., Parce qu'elles manipulent des objets fondamentalement abstraits, les lois mathématiques ont une validité indépendante du contexte dans lequel elles s'appliquent. Autrement dit, 2 + 2 font 4, que l'on compte des pommes, des schtroumpfs, ou des années-lumière. Par extension, il a longtemps été considéré qu'il en était de même pour la pensée mathématique chez l'humain, perçue comme objective et indépendante des contenus sur lesquels elle s'exerce. Pourtant, un nombre grandissant de travaux s'accordent à dire que la logicité n'est pas seule à gouverner la pensée humaine, que le contexte dans lequel il se trouve influence ses raisonnements, et que la pensée mathématique est fondamentalement incarnée. Ainsi, notre thèse est que les connaissances générales des individus influencent considérablement leurs représentations des situations numériques. En particulier, nous faisons l'hypothèse que les savoirs non-mathématiques des individus au sujet des entités décrites dans un problème peuvent façonner leur représentation de la situation, les poussant à en réaliser un encodage soit cardinal, soit ordinal. Nous commençons par présenter un modèle conceptuel visant à décrire les interactions entre la sémantique du monde et la sémantique mathématique évoquées à la lecture d'un problème arithmétique à énoncé verbal. Nous faisons la prédiction que les connaissances générales sur le monde influent sur l'encodage, le recodage et la résolution des problèmes arithmétiques à énoncés verbaux, notamment en induisant des représentations soit cardinales, soit ordinales. Nous évaluons cette hypothèse grâce à 16 expériences fondées sur l'étude d'énoncés isomorphes implémentés avec certaines entités censées susciter un encodage cardinal (poids, prix, collections d'éléments) ou ordinal (durées, hauteurs, nombre d'étages). Nous montrons la robustesse de ces effets au travers d'une variété de tâches, qu'il s'agisse de classification, comparaison, résolution, production graphique, jugement de solubilité, évaluation de solution, reconnaissance, transfert et rappel de problèmes. La prévalence des effets observés est déterminée par des indices comportementaux (performances, temps de réponse, sélection de stratégies) et physiologiques (oculométrie et pupillométrie), collectés auprès d'enfants du CE1 au CM2, ainsi que d'adultes tout venants, d'enseignants en mathématiques et d'experts mathématiciens. Les riches enjeux éducatifs portés par ces questions sont discutés de même que les perspectives ouvertes par la prise en compte des effets de congruence sémantique. Nous concluons sur les contraintes que les contenus opèrent sur le raisonnement.

Unilateral hearing loss (UHL) alters binaural cues affecting speech comprehension and sound localisation. While many patients with UHL perform poorly on binaural tasks, some are able to adapt to monaural deficit. We aimed to identify patients with UHL who use compensatory strategies and to explore the neural correlates of this adaptation using Mismatch Negativity (MMN). We recruited 21 patients with UHL and we separated them into three groups using cluster analysis based on measures of binaural processing. The resulting groups were referred to as the better, moderate and poorer performers clusters (BPC, MPC and PPC). We measured the MMN elicited by deviant sounds located 10°, 20° or 100° away from a standard sound. We found that the BPC group had a significant MMN for all three deviant sounds, as in a group of normal-hearing controls. In contrast, the PPC group and normal-hearing controls with an earplug did not have a significant MMN for the 10° and 20° deviations. For the 100° deviation, the scalp distribution was found to be maximal over central regions in the BPC group, while the PPC group showed a more frontal distribution. Differences were also found for the N100 evoked by standard sounds, with the BPC group showing a contralateral pattern of activation, as in the controls, and the PPC group showing more symmetrical hemispheric activation. These results indicate that patients with UHL can develop adaptive strategies that are reflected by sound processing differences at the cortical level.

International audience; An important function of the brain is to predict which stimulus is likely to occur based on the perceived cues. The present research studied the branching behavior of a computational network model of populations of excitatory and inhibitory neurons, both analytically and through simulations. Results show how synaptic efficacy, retroactive inhibition and short-term synaptic depression determine the dynamics of selection between different branches predicting sequences of stimuli of different probabilities. Further results show that changes in the probability of the different predictions depend on variations of neuronal gain. Such variations allow the network to optimize the probability of its predictions to changing probabilities of the sequences without changing synaptic efficacy.

Auditory rhythms are ubiquitous in music, speech, and other everyday sounds. Yet, it is unclear how perceived rhythms arise from the repeating structure of sounds. For speech, it is unclear whether rhythm is solely derived from acoustic properties (e.g., rapid amplitude changes), or if it is also influenced by the linguistic units (syllables, words, etc.) that listeners extract from intelligible speech. Here, we present three experiments in which participants were asked to detect an irregularity in rhythmic speech sequences. In each experiment, we reduce the number of possible stimulus properties that differ between intelligible and unintelligible speech sounds and show that these acoustically-matched intelligibility conditions nonetheless lead to differences in rhythm perception. In Experiment 1, we replicate a previous study showing that rhythm perception is improved for intelligible (16-channel vocoded) as compared to unintelligible (1-channel vocoded) speech – despite near-identical broadband amplitude modulations. In Experiment 2, we use spectrally-rotated 16-channel speech to show the effect of intelligibility cannot be explained by differences in spectral complexity. In Experiment 3, we compare rhythm perception for sine-wave speech signals when they are heard as non-speech (for naïve listeners), and subsequent to training, when identical sounds are perceived as speech. In all cases, detection of rhythmic regularity is enhanced when participants perceive the stimulus as speech compared to when they do not. Together, these findings demonstrate that intelligibility enhances the perception of speech rhythm, which is hence linked to processes that extract abstract linguistic units from sound.

International audience; Improving user performances is one of the major issues for Motor Imagery (MI)-based BCI control. MI-BCIs exploit the modulation of sensorimotor rhythms (SMR) over the motor and sensorimotor cortices to discriminate several mental states and enable user interaction. Such modulations are known as Event-Related Desynchronization (ERD) and Synchronization (ERS), coming from the mu (7-13 Hz) and beta (15-30 Hz) frequency bands. This kind of BCI opens up promising fields, particularly to control assistive technologies, for sport training or even for post-stroke motor rehabilitation. However, MI-BCIs remain barely used outside laboratories, notably due to their lack of robustness and usability (15 to 30% of users seem unable to gain control of an MI-BCI). One way to increase user performance would be to better understand the relationships between user traits and ERD/ERS modulations underlying BCI performance. Therefore, in this article we analyzed how cerebral motor patterns underlying MI tasks (i.e., ERDs and ERSs) are modulated depending (i) on nature of the task (i.e., right-hand MI and left-hand MI), (ii) the session during which the task was performed (i.e., calibration or user training) and (iii) on the characteristics of the user (e.g., age, gender, manual activity, personality traits) on a large MI-BCI data base of N=70 participants. One of the originality of this study is to combine the investigation of human factors related to the user's traits and the neurophysiological ERD modulations during the MI task. Our study revealed for the first time, associations between ERD and both age, level of study, impression management and anxiety.

International audience; BACKGROUND AND AIM: NSLBP is characterized by symptoms without clear patho-anatomical causes and cLBP has been identified as one of the leading global causes of disability [1]. The majority of clinical trials assess cNSLBP using scales or questionnaires reporting an influence of cognitive, emotional and behavioral factors [2]. Previous studies have evaluated the motor consequences of cNSLBP using biomechanical analysis, showing alterations in the kinematics and dynamics of locomotion [3,4]. However, few studies have evaluated cNSLBP participants in ecological situations, such as walking with obstacles or avoidance, allowing a simultaneous evaluation of cognitive, perceptual and motor components in a situation closer to the one encountered in daily life. In this context, using a horizontal aperture crossing paradigm [5], this study aimed to 1) understand the effect of cNSLBP in action strategies and (2) identify factors that may influence these decisions. METHODS: Healthy adults (N=15) and cNSLBP adults (N=15) performed a walking protocol composed of 3 random blocks of 19 trials with aperture ranging from 0.9 to 1.8 x shoulder width. The dimensions of the obstacle causing an individual to change their actions (shoulders rotation, velocity, trunk stability) is referred to as the Critical Point (CP). RESULTS: In these preliminary results considering shoulder width, welch's t-test showed that the average CP in the healthy group was significantly larger (1.20 SD = 0.052) than the one of cNSLBP group (1.15, SD = 0.029) (t(20.08) = 3.07, p

International audience; Resting-state functional magnetic resonance imaging (fMRI) is a common translational method to evaluate brain functional connectivity (FC) in preclinical neurologic applications. However, unlike human studies, preclinical fMRI studies are usually performed under anesthetic condition. The confounding effect of the anesthesia on fMRI measurements is not clear. Indeed, a controversy exists between those who claim that anesthesia change FC (Paasonen et al., 2018) and other who maintain that FC is preserved (Becq et al., 2020). Our hypothesis is that physiological changes induced by anesthesia could explain this discrepancy. While in human studies, fMRI analysis generally includes cleaning of physiological-noise (Glover et al., 2000; Kassinopoulos & Mitsis, 2019), preclinical study processing is rather often limited to a low-pass temporal filtering. We aimed first to demonstrate that the global MRI signal of animal brain includes, like in human, a physiological component. Second, that a normalization of this component based on global signal can reduce variability of FC assessment.

International audience; Cerebral fMRI is a useful imaging tool that allows to visualize neuronal activity based on blood oxygen levels. However, except the neuronal component of interest, fMRI signal contains “noise” components due to physiological processes (heartbeat, respiration...). Litterature contains attempts to estimate this part of the signal, but not to measure it. This study aims to measure the respective impact of cardiac pulse and respiratory cycle on MRI signal in human brain and its regions with short TR.

During speech, the auditory feedback involves both an aerial component picked up by the external ear,and an internal vibration : the ‘bone conduction’ component. While a speaker hears both components, alistener only hears the aerial part. Although half of the cochlear signal comes from internal conduction,the information it conveys, and how it impacts oral motor control, is still unclear. In this study, weconsidered the sound emitted by the eardrum and ear canal during speech as a proxy for internalsound. After recording aerial and internal sound, we made use of a voice conversion method toevaluate their informational differences. As expected, nasal vowels and consonants correlate withstronger internal signal ; more surprisingly, we observe also more internal information during stop andfricative consonants. Overall, the summation of internal and aerial feedback leads to clearer formantictrajectories, which may facilitate speech motor control., Lorsqu'on parle, le retour auditif se décompose en une voie aérienne et une voie interne ou 'par conduction osseuse'. Un locuteur entend les deux composantes, contrairement au récepteur. Alors que la moitié du signal cochléaire est interne, on connaît mal l'information qu'il véhicule et comment elle impacte le contrôle moteur oral. Dans cette étude, nous considérons le son émis par le conduit auditif pendant la production de parole comme indicateur du signal interne. Après enregistrement des signaux internes et aériens, une méthode de conversion de voix nous permet d'évaluer leurs différences informationnelles. Comme anticipé, les voyelles et consonnes nasales corrèlent avec plus d'intensité et d'information osseuse ; de manière moins attendue, on observe également plus d'information osseuse pour les consonnes occlusives et fricatives. De façon globale, la somme des retours acoustiques aérien et osseux amène une lisibilité supérieure des trajectoires formantiques qui pourrait faciliter le contrôle de la production de parole.

Background This work aimed to investigate the potential pathways involved in the association between social and lifestyle factors, biomarkers of Alzheimer’s disease and related dementia (ADRD), and cognition. Methods The authors studied 2323 participants from the Memento study, a French nationwide clinical cohort. Social and lifestyle factors were education level, current household incomes, physical activity, leisure activities, and social network from which two continuous latent variables were computed: an early to midlife (EML) and a latelife (LL) indicator. Brain magnetic resonance imaging (MRI), lumbar puncture, and amyloid-positron emission tomography (PET) were used to define three latent variables: neurodegeneration, small vessel disease (SVD), and AD pathology. Cognitive function was defined as the underlying factor of a latent variable with four cognitive tests. Structural equation models were used to evaluate cross-sectional pathways between social and lifestyle factors and cognition. Results Participants’ mean age was 70.9 years old, 62% were women, 28% were apolipoprotein-ε4 carriers, and 59% had a Clinical Dementia Rating (CDR) score of 0.5. Higher early to midlife social indicator was only directly associated with better cognitive function (direct β = 0.364 (0.322; 0.405), with no indirect pathway through ADRD biomarkers (total β = 0.392 (0.351; 0.429)). In addition to a direct effect on cognition (direct β = 0.076 (0.033; 0.118)), the association between latelife lifestyle indicator and cognition was also mostly mediated by an indirect effect through lower neurodegeneration (indirect β = 0.066 (0.042; 0.090) and direct β = − 0.116 (− 0.153; − 0.079)), but not through AD pathology nor SVD. Conclusions Early to midlife social factors are directly associated with higher cognitive functions. Latelife lifestyle factors may help preserve cognitive functions through lower neurodegeneration.

The pulvinar is a heterogeneous thalamic nucleus, which is well developed in primates. One of its subdivisions, the medial pulvinar, is connected to many cortical areas, including the visual, auditory, and somatosensory cortices, as well as with multisensory areas and premotor areas. However, except for the visual modality, little is known about its sensory functions. A hypothesis is that, as a region of convergence of information from different sensory modalities, the medial pulvinar plays a role in multisensory integration. To test this hypothesis, 2 macaque monkeys were trained to a fixation task and the responses of single-units to visual, auditory, and auditory–visual stimuli were examined. Analysis revealed auditory, visual, and multisensory neurons in the medial pulvinar. It also revealed multisensory integration in this structure, mainly suppressive (the audiovisual response is less than the strongest unisensory response) and subadditive (the audiovisual response is less than the sum of the auditory and the visual responses). These findings suggest that the medial pulvinar is involved in multisensory integration.

International audience; Temporal contingency is a key factor in associative learning but remains weakly investigated early in life. Few data suggest simultaneous presentation is required for young to associate different stimuli, whereas adults can learn them sequentially. Here, we investigated the ability of newborn rabbits to perform sensory preconditioning and second-order conditioning using trace intervals between odor presentations. Strikingly, pups are able to associate odor stimuli with 10- and 30-sec intervals in sensory preconditioning and second-order conditioning, respectively. The effectiveness of higher-order trace conditioning in newborn rabbits reveals that very young animals can display complex learning despite their relative immaturity.

International audience; We augment the recently introduced SPARKLING algorithm and propose an improved mathematical formulation that takes the temporal dependence of the MR signal into account. This prevents the trajectories from sampling similar portions of k-space at different times, thereby reducing distortions and blurring induced by $B_0$ inhomogenieties. Overall, these trajectories present a smooth distribution over time in k-space and Minimized Off-Resonance Effects (MORE-SPARKLING), verified both retrospectively and prospectively with scans performed in vivo at 3T on a healthy volunteer.

International audience; Background and purpose: Repetitive transcranial magnetic stimulation (rTMS) has been proposed to treat functional neurological disorders. Here, the aim was to assess the efficacy of rTMS to treat functional paralysis in a controlled randomized trial.Methods: Patients received two sessions of active or sham 0.25 Hz rTMS (60 stimuli each), with a 1-day interval, applied over the motor cortex contralateral to the paralysis. The primary outcome was the number of patients with an increase in motor score between baseline and after the second rTMS session, rated by two investigators blinded to the treatment allocation. Secondary outcomes were changes in global and fine motor scores between groups after rTMS, and the occurrence of adverse events.Results: Sixty-two patients (46 female; mean [SD] age, 35.2 [13.9] years) were enrolled and randomized. Thirteen out of 32 (41%) and 11/30 (37%) patients had increased motor strength after active or sham rTMS, respectively (p = 0.80). Changes in both global and fine motor scores after rTMS relative to baseline were also not significantly different between treatment groups (median difference in the global motor score 0.62 [0.83] and 0.37 [0.61], and in the fine motor scores 0.12 [0.18] and 0.08 [0.11], in active and sham rTMS groups, respectively; p = 0.14). Six serious adverse events, consisting of three cephalalgia in the active group and two cephalalgia and one asthenia in the sham group, were observed.Conclusions: Two sessions of sham or active low frequency rTMS were effective to improve functional paralysis, suggesting a placebo effect of this non-invasive brain stimulation technique.

International audience; Stroke leaves around 40% of surviving patients dependent in their activities of daily living, notably due to severe motor disabilities [Inserm, 2019]. Brain-Computer Interfaces (BCIs) have been shown to be efficient for improving motor recovery after stroke [Cervera et al., 2018], but this efficiency is still far from the level required to achieve the clinical breakthrough expected by both clinicians and patients. While technical levers of improvement have been identified, they are insufficient: fully optimised BCIs are pointless if patients and clinicians do not want to use them [Blain-Moraes et al., 2012].We hypothesise that improving BCI acceptability and acceptance, by better informing stakeholders about BCI functioning and by personalising the BCI-based rehabilitation procedures to each patient, respectively, will favour engagement in the rehabilitation process and result in an increased efficiency.Our first objective was to identify the factors influencing the intention to use (IU) BCIs [Davis, 1989]. Based on the literature, we constructed a model of BCI acceptability and adapted it in questionnaires addressed to the general population (n=753) and post-stroke patients (n=33). Videos were included, one about the general functioning of BCIs, the second about their relevance for rehabilitation.We used random forest algorithms to explain IU based on our model's factors. After the first video, IU was mainly explained by subjective and personal factors, i.e., perceived usefulness (PU), perceived ease of use (PEOU) and BCI playfulness for the general population, and PU, autonomy and engagement in the rehabilitation for the patients. After the second video, the explanatory factors became more scientific/rational, with PU, cost-benefits ratio and scientific relevance for the general population, and PU, scientific relevance and ease of learning for patients.The shift of main explanatory factors (before/after second video) from subjective representations to scientific arguments highlights the impact of providing patients with clear information regarding BCIs.

In Alzheimer’s disease, the tauopathy is known as a major mechanism responsible for the development of cognitive deficits. Early biomarkers of such affectations for diagnosis/stratification are crucial in Alzheimer’s disease research, and brain connectome studies increasingly show their potential establishing pathology fingerprints at the network level. In this context, we conducted an in vivo multimodal MRI study on young Thy-Tau22 transgenic mice expressing tauopathy, performing resting state functional MRI and structural brain imaging to identify early connectome signatures of the pathology, relating with histological and behavioural investigations. In the prodromal phase of tauopathy, before the emergence of cognitive impairments, Thy-Tau22 mice displayed selective modifications of brain functional connectivity involving three main centres: hippocampus (HIP), amygdala (AMG) and the isocortical areas, notably the somatosensory (SS) cortex. Each of these regions showed differential histopathological profiles. Disrupted ventral HIP-AMG functional pathway and altered dynamic functional connectivity were consistent with high pathological tau deposition and astrogliosis in both hippocampus and amygdala, and significant microglial reactivity in amygdalar nuclei. These patterns were concurrent with widespread functional hyperconnectivity of memory-related circuits of dorsal hippocampus—encompassing dorsal HIP-SS communication—in the absence of significant cortical histopathological markers. These findings suggest the coexistence of two intermingled mechanisms of response at the functional connectome level in the early phases of pathology: a maladaptive and a likely compensatory response. Captured in the connectivity patterns, such first responses to pathology could further be used in translational investigations as a lead towards an early biomarker of tauopathy as well as new targets for future treatments.

International audience; Purpose:The main objective of this study was to provide further information concerning the validity of patient-reported executive function (EF) in survivors of primary brain tumor (PBT) compared with a report provided by each patient’s caregiver.Methods: Forty survivors of PBT, 40 non-cancer controls and their proxies completed an assessment of functional executive disorders (e.g., planning, inhibition, shifting, action initiation). Comparisons of self and informant EF reports were examined, for both patients and non-cancer controls. The extent of the concordance between patients’ reports and their caregivers’ reports was also determined.Results: PBT survivors and their caregivers reported more problems related to EF in contrast with the non-cancer comparison group (significant differences). There was a high level of agreement between patients’ and caregivers’ ratings within the patient group.Conclusions: This study provides evidence suggesting that at an average of 3.67 (SD = 2.31) years following treatment for a PBT, EF difficulties are reported by patients and their caregivers. This study establishes a consistency between what is reported by survivors and what is reported by those who frequently interact with them. Further research investigating the link between these ratings and quality of life as well as other functions is encouraged.Implications for Cancer Survivors: This study’s results demonstrate the importance of listening to PBT survivors’ perception of EF difficulties. While not confirmed by neuropsychological evaluations, the functional executive challenges reported by these survivors’ close relatives reflect what PBT survivors themselves report. Specialists should pay close attention to these difficulties to guarantee optimal post-cancer care.

Longevity is influenced by genetic and environmental factors, but the underlying mechanisms remain elusive. Here, we functionally characterise a Drosophila small nucleolar RNA (snoRNA), named jouvence whose loss of function reduces lifespan. The genomic region of jouvence rescues the longevity in mutant, while its overexpression in wild-type increases lifespan. Jouvence is required in enterocytes. In mutant, the epithelium of the gut presents more hyperplasia, while the overexpression of jouvence prevents it. Molecularly, the mutant lack pseudouridylation on 18S and 28S-rRNA, a function rescued by targeted expression of jouvence in the gut. A transcriptomic analysis performed from the gut reveals that several genes are either up- or down-regulated, while restoring the mRNA level of two genes (ninaD or CG6296) rescue the longevity. Since snoRNAs are structurally and functionally well conserved throughout evolution, we identified putative jouvence orthologue in mammals including humans, suggesting that its function in longevity could be conserved., Small non-coding RNAs contribute to the regulation of aging. Here the authors identify a small nucleolar RNA, the snoRNA jouvence, which extends the lifespan of fruit flies through its function in the gut, and is conserved in humans.

International audience; In the field theories in physics, any particular region of the presumed space-time continuum and all interactions between elementary objects therein can be objectively measured and/or accounted for mathematically. Since this does not apply to any of the field theories, or any other neural theory, of consciousness, their explanatory power is limited. As discussed in detail herein, the matter is complicated further by the facts than any scientifically operational definition of consciousness is inevitably partial, and that the phenomenon has no spatial dimensionality. Under the light of insights from research on meditation and expanded consciousness, chronic pain syndrome, healthy ageing, and eudaimonic well-being, we may conceive consciousness as a source of potential energy that has no clearly defined spatial dimensionality, but can produce significant changes in others and in the world, observable in terms of changes in time. It is argued that consciousness may have evolved to enable the human species to generate such changes in order to cope with unprecedented and/or unpredictable adversity. Such coping could, ultimately, include the conscious planning of our own extinction when survival on the planet is no longer an acceptable option.

L'intelligibilité (mesure dans laquelle le message oral d'un locuteur est compris par un interlocuteur), la compréhensibilité (facilité/difficulté pour comprendre un message oral) et la perception de l'accent étranger (identification de la parole non-native) sont trois dimensions fondamentales dans l'enseignement de la prononciation d'une L2 (Munro & Derwin 1995, 2021). Dans des documents de référence tels que le CECRL, la compétence phonique d'un apprenant est définie en termes d'être compréhensible (A1), être compris avec une prononciation claire (A2), être intelligible (B1) ou maîtriser tout l'éventail des traits phonologiques de la langue cible de façon à être toujours intelligible (C2). Les études examinant ces aspects ont permis de mieux identifier les patrons phonétiques prioritaires à enseigner en anglais L2 (Levis 2020). Néanmoins, l'intelligibilité, la compréhensibilité et la perception de l'accent étranger ont été largement délaissées dans les recherches empiriques en français L2 (Didelot et al. 2019, Bergeron & Trofimovich 2017, Lappin-Fortin 2018).Cette contribution essaie d'étudier le rapport de ces trois dimensions avec le développement phonologique en FLE. Cette étude examine les effets de deux niveaux de maitrise de FLE dans l'intelligibilité, la compréhensibilité et le degré d'accent étranger chez des locuteurs natifs du français. Notre hypothèse est que la parole du groupe B1 serait plus intelligible, plus compréhensible et associée à accent étranger moins fort que celle du groupe A2. Pour ce faire, 12 apprenants hispanophones ayant un niveau A2 (n = 6) et B1 (n = 6) en FLE, ainsi que 5 locuteurs natifs (de région parisienne) ont été enregistrés lors d'une tâche d'interaction orale. 51 énoncés ont été extraits de ce corpus et ont été évalués par 20 locuteurs natifs du français(Île-de-France). Les juges ont d'abord transcrit orthographiquement les stimuli afin de calculer le pourcentage de mots reconnus (intelligibilité). Ils ont ensuite évalué le degré de difficulté pour comprendre les stimuli (compréhensibilité) et le degré d'accent étranger perçu via une échelle de Likert de 9 points.Nous avons également examiné les stimuli selon trois dimensions phonétiques : (i) taux d'erreurs dans la prononciation de segments via les distances de Levenshtein (Santiago 2018, Weiling et al. 2014), (ii) évaluation de la prosodie des stimuli manipulés avec un filtre passe-bas par 3 prosodistes natifs du français et (iii) des patrons rythmiques (débit d'articulation, nombre de pauses et leur durée).Les résultats des modèles linéaires mixtes montrent que les apprenants hispanophones du groupe B1 ont une tendance à être plus intelligibles et plus compréhensibles que le groupe A2, mais ces différences ne sont pas statistiquement significatives (Figures 1 & 2). Le degré d'accent étranger semble diminuer légèrement avec le niveau de langue, mais sans atteindre la significativité statistique non plus (Figure 3). Les corrélations (méthode Kendall) montrent que les aspects suprasegmentaux (prosodie et rythme) ont eu un des effets plus importants chez les juges que les erreurs au niveau segmental (niveau B1 seulement). Contrairement à notre hypothèse, la compétence phonétique entre ces deux groupes n'évolue pas de manière homogène. Nous discutons de l'importance de ces résultats dans la didactique de la prononciation en FLE.

International audience; A typical Motor Imagery (MI) experimental pipeline is composed of an EEG data acquisition phase, followed by an analysis phase to train a classification algorithm (such as LDA). The training uses features extracted from the acquired data such as spectral power for a subset of sensors and frequencies, in which desynchronization can be observed between the MI tasks. In the final phase of the experiment, the trained classifier is used in an online setup.The feature selection phase is crucial for the optimal functioning of a BCI system, but the large number of parameters can make it a long step of trial-and-error, not acceptable in clinical settings. Training a classification algorithm can be challenging and time consuming as it may include multiple manipulations and datatype conversions with external softwares.Here, we propose a new Python-based framework to manage the whole experimental pipeline smoothly, integrating seamlessly with OpenViBE. We focused our work on feature analysis, selection, and classifier training. An easy-to-use GUI allows to keep track of the multiple acquired EEG signal files, and to process them for analysis and training. Convenient tools allow to compute spectral features and visualize them in the form of statistical R² maps, PSD, scalp topography and ERD/EDS time-frequency maps, for selected sensors or frequency bands, combining trials across multiple runs. Finally, a set of runs can be chosen for training the classification algorithm with only a few clicks and seconds of processing. All signal processing operations use OpenViBE in the background, transparent to the user.This framework has been successfully validated on real EEG data obtained with a Graz MI protocol. It allows the experimenter to identify the underlying brain processes during MI and choose the best combination of features for the subsequent classification. Work is ongoing to add further functionalities, notably functional connectivity.

While training on several examples is known to be a decisive step in learning how to flexibly use mathematical concepts in different situations, selecting the optimal sequence of examples remains a significant challenge for mathematics education (De Bock, Deprez, Van Dooren, Roelens, & Verschaffel, 2011). Specifically, identifying which examples may help learners develop their cognitive flexibility - the ability to consider the same problem from different perspectives and find its solution regardless of its wording - is a crucial stake for educational psychology (Clément, 2022). This study investigates whether the cognitive load attached to a problem may either facilitate or hinder one’s ability to find an optimal path of resolution. We analyze the interactions between cognitive flexibility and cognitive load using arithmetic word problems whose solution requires a perspective change (Gros, Thibaut, & Sander, 2021). In two online experiments, we asked adults to solve such problems while varying the extraneous cognitive load of the task, either by means of a dual-task paradigm, or by changing the difficulty of the calculations leading to the solution. We hypothesized that reducing a problem’s cognitive load may be a powerful lever to help learners find a problem’s optimal solution. We analyzed the rate of use of the different solving strategies to assess the extent to which the cognitive load imposed on a problem influences the expression of cognitive flexibility among adults. By providing a finer understanding of the interactions between cognitive flexibility and cognitive load in arithmetic reasoning, we intend to shed a new light on the crucial learning processes involved in problem solving, while providing guidelines regarding which examples to use to foster cognitive flexibility in mathematics classrooms.

International audience

How do adults think about situations involving numbers, and how can we investigate the nature of the mental representations they construct? To tackle this question, we created arithmetic word problems devised to promote contrasting representations and solving strategies. Following recent work on the perception of cardinality and ordinality (Gros, Thibaut, & Sander, 2021), we hypothesized that the use of specific quantities (weights, prices, collections) would foster a cardinal representation of the problems, whereas other quantities (durations, heights, number of floors) would favor an ordinal representation instead. The problems we created were thought to be easily solvable from an ordinal point of view but should require an extra step when solved from a cardinal perspective. We recorded the eye movements of pre-service teachers (N = 50) engaged in a solution validity assessment task on 18 such problems. We compared participants’ gaze patterns on the problems to gather insights into their encoded representations. On problems featuring cardinal quantities, we found that specific sentences describing elements relevant in a cardinal understanding of the problems but irrelevant otherwise were looked at longer and were the focus of a higher number of backward eye movements. Additionally, increase in pupil dilation on correctly solved cardinal problems supported the idea that participants needed to engage in an additional step of semantic recoding only on cardinal problems. Overall, the results support the growing line of evidence that daily-life knowledge about the quantities featured in a problem may interfere with its solving by promoting one of two competing representations.

International audience; Primary (interceptive) saccades toward a moving target have been proposed to be the outcome of the summation of signals “computed” by two parallel and distinct pathways in the brain. One computation would estimate the location where the target first appeared whereas the other would calculate the subsequent target displacement amplitude from velocity signals. These computations would involve activity propagating through a pathway involving the superior colliculus (snapshot of position) and another involving the cerebellum (motion integration).Rather skeptical that kinematic parameters could be embedded within the brain activity and that massively distributed and recurrent neuronal networks would subtend human-like arithmetic computations, we re-examined this theory. We recorded the activity of saccade-related neurons in the superior colliculus with the aim to verify whether the population bursting activity would include cells coding for saccade vectors corresponding to the current and perhaps the future location of the target. Thus, we found that during the saccade-related burst, the active assembly consists of a continuum of commands, ranging from those related to antecedent target locations to commands related to its current location. Regarding the other pathway, we tested its contribution by inactivating one of its output nuclei, the caudal fastigial nucleus. Like saccades toward a static target, the horizontal component of interceptive saccades became hypometric when directed toward the contralesional side and hypermetric when they were ipsilesional. The horizontal dysmetria depended on target velocity, but the use of accelerating or decelerating targets revealed that velocity was not the crucial parameter.Altogether, our investigations lead to a viewpoint from which basic intrinsic properties of the brain suffice to explain the generation of accurate visually-guided (saccadic and pursuit) eye movements without considering that kinematic notions would be embedded within the brain activity and that the brain networks would perform arithmetic computations upon them.

International audience; A key challenge when studying human-agent interaction, is the evaluation of user's experience. In virtual reality, this question is addressed through the study of the sense of presence and copresence, generally assessed thanks to well-grounded subjective post-experience questionnaires. In this article, we aim at correlating objective multimodal cues produced by users to their subjective sense of presence and co-presence. Our study is based on a human-agent interaction corpus collected in task-oriented context: a virtual environment aiming at training doctors to break bad news to a patient played by a virtual agent. Based on a corpus study, we have used machine learning approaches to explore the possibility of automatically predicting the sense of presence and co-presence of the user thanks to specific multimodal behavioral cues. The performance of random forests models demonstrates the capacity to automatically and accurately predict the level of presence. It also shows the relevance of a multimodal model, based on verbal and non-verbal behavioral cues as objective measures of presence.

Developmental Coordination Disorder (DCD) is a pathological condition characterized by impaired motor skills. Current theories advance that a deficit of the internal models is mainly responsible for DCD children’s altered behavior. Yet, accurate movement execution requires not only correct movement planning, but also integration of sensory feedback into body representation for action (Body Schema) to update the state of the body. Here we advance and test the hypothesis that the plasticity of this body representation is altered in DCD. To probe Body Schema (BS) plasticity, we submitted a well-established tool-use paradigm to seventeen DCD children, required to reach for an object with their hand before and after tool use, and compared their movement kinematics to that of a control group of Typically Developing (TD) peers. We also asked both groups to provide explicit estimates of their arm length to probe plasticity of their Body Image (BI). Results revealed that DCD children explicitly judged their arm shorter after tool use, showing changes in their BI comparable to their TD peers. Unlike them, though, DCD did not update their implicit BS estimate: kinematics showed that tool use affected their peak amplitudes, but not their latencies. Remarkably, the kinematics of tool use showed that the motor control of the tool was comparable between groups, both improving with practice, confirming that motor learning abilities are preserved in DCD. This study thus brings evidence in favor of an alternative theoretical account of the DCD etiology. Our findings point to a deficit in the plasticity of the body representation used to plan and execute movements. Though not mutually exclusive, this widens the theoretical perspective under which DCD should be considered: DCD may not be limited to a problem affecting the internal models and their motor functions, but may concern the state of the effector they have to use.

Background Air pollution exposure is one of the modifiable risk factors of cognitive decline. We aimed to test the association between exposure to several outdoor air pollutants and domain-specific cognitive performance. Methods In this cross-sectional study, we used data from the enrolment phase of the French CONSTANCES cohort. From the 220 000 people (aged 18-69 years) randomly recruited in the French CONSTANCES cohort, participants aged 45 years old or older (104 733 people) underwent a comprehensive cognitive assessment (verbal episodic memory, language skills, and executive functions). After exclusion of those who were not suitable for our analysis, 61 462 participants with available data were included in the analyses. We used annual mean concentrations at residential addresses, derived from land-use regression models, to assign exposure to particulate matter with aerodynamic diameters less than 2·5 μm (PM2·5), nitrogen dioxide (NO2), and black carbon. We used multiple linear regression models with different covariate adjustments to test the associations between each pollutant and cognitive outcomes. We did several sensitivity analyses, including multilevel modelling, meta-analysis by centre of recruitment, and exclusion of specific population groups. Findings We found significantly poorer cognitive function, especially on semantic fluency and domains of executive functions, with an increase in exposure to black carbon and NO2. Exposure to PM2·5 was mainly significant for the semantic fluency test. We found that decrease in cognitive performance with an increase of one interquartile range of exposure ranged from 1% to nearly 5%. The largest effect size (percentage decrease) for both PM2.5 and NO2 was found for the semantic fluency test (PM2.5 4·6%, 95% CI 2·1-6·9 and NO2 3·8%, 1·9-5·7), whereas for black carbon, the largest effect size was found for the digit symbol substitution test of the domains of executive functions (4·5%, 2·7-6·3). Monotonic and linear exposure-response associations were found between air pollution exposure and cognitive performance, starting from a low level of exposures. Interpretation Significantly poorer cognitive performance was associated with exposure to outdoor air pollution even at low levels of exposure. This highlights the importance of further efforts to reduce exposure to air pollution. Funding The Caisse Nationale d'Assurance Maladie, and partly funded by Merck Sharp & Dohme and L'Oréal, the French National Research Agency, and Fondation de France. Translation For the French translation of the abstract see Supplementary Materials section.

Neurocognitive disorders are frequent among chronic kidney disease (CKD) patients. Identifying and characterizing cognitive impairment (CI) can help to assess the ability of adherence to CKD risk reduction strategy, identify potentially reversible causes of cognitive decline, modify pharmacotherapy, educate the patient and caregiver and provide appropriate patient and caregiver support. Numerous factors are associated with the development and progression of CI in CKD patients and various conditions can influence the results of cognitive assessment in these patients. Here we review clinical warning signs that should lead to cognitive screening; conditions frequent in CKD at risk to interfere with cognitive testing or performance, including specificities of cognitive assessment in dialysis patients or after kidney transplantation; and available tests for screening and observed cognitive patterns in CKD patients., Graphical Abstract Graphical abstract

Friction is a force we have to deal with in everyday life when we handle objects or slide them. In this thesis, participants performed a striking motion (with the index finger) to slide a cubic shaped plastic object through a gutter toward a target distance. Depending on the conditions, the experimental factors manipulated are the material of the surface on which the object slides, the inclination of the surface (-10°, 0°, or +10°) and the target distance, for a given number of trials.The analysis of the spatial error (between the object and the target) as well as the initial speed of the object after impact with the finger suggests that, over the trials, the movement is parameterized to reduce the spatial error in order to calibrate an internal model of the coefficient of friction (µ subjective) for a given surface. Subsequently, this µ subjective can be generalized when the condition of inclination and/or distance is changed, or can be recalibrated. The biomechanical analysis shows that, in the simplest conditions, participants adopt the same motorstrategy by recruiting rotation of only one segment (the hand) to provide the kinetic energy needed to reach the target. It is only with increasing task constraints that some participants decide to adopt a new motor strategy by adding a degree of freedom (forearm rotation), with greater success in the most difficult conditions. Our results also show that some participants prefer to keep one spatiotemporal parameter invariant (amplitude or duration of the strike) and to vary the other for controlling the speed at impact; while other participants vary both parameters favoring the control of acceleration before impact.In conclusion, we provide evidence that, through the repetition of trials, the brain builds an internal model of friction that allows it to parameterize the ballistic striking movement in order to regulate the amount of kinetic energy required at impact, for transmitting to the object the appropriate initial velocity so that it slides to a target distance., La friction est une force avec laquelle nous devons composer dans la vie de tous les jours, lorsque nous manipulons des objets ou que nous les faisons glisser. Dans la présente thèse, les participants ont effectué un mouvement de frappe (avec l'index) pour faire glisser un objet plastique de forme cubique dans une gouttière jusqu'à une distance cible. Selon les conditions, les facteurs expérimentaux manipulés sont : le matériau de la surface sur laquelle l'objet glisse, l'inclinaison de la surface (-10°, 0°, ou +10°) et la distance cible, pour un nombre d'essais donné.L'analyse de l'erreur spatiale (entre l'objet et la cible) ainsi que la vitesse initiale de l'objet après impact avec le doigt suggèrent qu‘au fil des essais, le mouvement est paramétré pour réduire l'erreur spatiale afin de calibrer un modèle interne du coefficient de friction (µ subjectif) pour une surface donnée. Par la suite, ce µ subjectif peut être généralisé lors d'un changement de condition d'inclinaison et/ou de distance, ou bien faire l'objet d'une recalibration. L'analyse biomécanique montre que dans les conditions les plus simples, les participants adoptent la rotation d'un seul segment (la main) afin de fournir l'énergie cinétique nécessaire pour atteindre la cible. Ce n'est qu'avec l'augmentation des contraintes de la tâche que certains participants décident d'adopter une nouvelle stratégie motrice en ajoutant un degré de liberté (rotation de l'avant-bras), avec un plus grand succès dans les conditions les plus difficiles. Nos résultats montrent également que certains participants préfèrent garder un paramètre spatiotemporel invariant (amplitude ou durée de la frappe) et faire varier l'autre pour contrôler la vitesse à l'impact; tandis que d'autres participants font varier les deux paramètres privilégiant le contrôle de l'accélération avant l'impact.En conclusion, nous apportons la preuve, qu'au travers de la répétition des essais, le cerveau se construit un modèle interne de la friction qui permet de paramétrer le mouvement balistique de frappe afin de réguler la quantité d'énergie cinétique nécessaire à l'impact, pour transmettre à l'objet la vitesse initiale appropriée afin qu'il glisse jusqu'à une distance cible.

My students made a beautiful presentation about smart cities of the future, and it got me thinking about how they, as representatives of the future, are going to live and where. What kind of food are they going to eat? How are they going to commute to work?

Background Fatty acids play prominent roles in brain function as they participate in structural, metabolic and signaling processes. The homeostasis of fatty acids and related pathways is known to be impaired in cognitive decline and dementia, but the relationship between these metabolic disturbances and common risk factors, namely the ɛ4 allele of the apolipoprotein E (ApoE-ɛ4) gene and sex, remains elusive. Methods In order to investigate early alterations associated with cognitive decline in the fatty acid-related serum metabolome, we here applied targeted metabolomics analysis on a nested case-control study (N=368), part of a prospective population cohort on dementia. Results When considering the entire study population, circulating levels of free fatty acids, acyl-carnitines and pantothenic acid were found to be increased among those participants who had greater odds of cognitive decline over a 12-year follow-up. Interestingly, stratified analyses indicated that these metabolomic alterations were specific for ApoE-ɛ4 non-carriers and women. Conclusions Altogether, our results highlight that the regulation of fatty acids and related metabolic pathways during ageing and cognitive decline depends on complex inter-relationships between the ApoE-ε4 genotype and sex. A better understanding of the ApoE-ɛ4 and sex dependent modulation of metabolism is essential to elucidate the individual variability in the onset of cognitive decline, which would help develop personalized therapeutic approaches.

Adaptive behaviors are defined as the set of behavioral and physiological reactions to a particular event arising from the external or internal environment. These adaptive behaviors have been studied at the species level but also at the level of the individual, showing that these behaviors are impacted by genetic selection, early experience and phylogeny. To understand the changes caused by these different factors, we need to study the brain, which is the seat of these behaviors, our hypothesis being that adaptive behaviors are linked to a specific organization of the brain. In order to study all the neurobiological substrates of adaptive behavior, it is essential to consider the brain regions involved in the perception of the environment, emotions and social behavior. To study all of these regions, we used Magnetic Resonance Imaging (MRI) which is the most suitable method to study the whole brain and to conduct a comparative study. During my thesis, I conducted an MRI study of the morphology of structures relating to sensory (olfactory, auditory, etc.) and socioemotional processes (amygdala, hippocampus, periaqueductal gray matter, etc.). To test the genetic selection hypothesis, we used two lines of Japanese quail, STI (Short Tonic Immobility) and LTI (Long Tonic Immobility), selected on their duration of tonic immobility, an adaptive behavior reflecting the emotionality of individuals. We found that genetic selection influences the morphology of brain regions involved in emotional but also sensory processes. To test the early experience hypothesis, we investigated the influence of early exposure to music as an environmental enrichment for lambs reared under mother-deprivation and with milk replacement, for which we know adaptive behaviors are altered.We have shown that this experience modifies their activity profile (especially emotional reactivity), the endocrine axis and the cerebral morphology of structures such as the caudate nucleus. To test the phylogenetic hypothesis, a comparative biology study was carried out on different wild species (deer mouse, cat-tailed lions, sea lions, etc.) during which we described the morphological specificities of brain structures known to be involved inadaptive behaviors.This thesis work shows, in different animal species, the involvement of genetic selection, early experience but also phylogeny in the anatomical plasticity of regions associated with adaptive behaviors., Les comportements adaptatifs sont définis comme l'ensemble des réactions comportementales et physiologiques à un évènement particulier issu de l'environnement externe ou interne. Les comportements adaptatifs ont été étudiés à l’échelle des espèces mais aussi à l’échelle des individus ce qui a permis de montrer que ces comportements sont impactés par la sélection génétique, l’expérience précoce et la phylogénie. Pour comprendre les modifications engendrées par ces différents facteurs, il est nécessaire d’étudier le cerveau qui est le siège de ces comportements, notre hypothèse étant que les comportements adaptatifs sont liés à une organisation spécifique de l'encéphale. Dans le but d’étudier l’ensemble des substrats neurobiologiques des comportements adaptatifs, il est indispensable de considérer les régions cérébrales impliquées dans la perception de l’environnement, les émotions et les comportements sociaux. Pour étudier l’ensemble de ces régions, nous avons utilisé l’Imagerie par Résonance Magnétique (IRM) qui est la méthode la plus appropriée pour étudier l’encéphale dans sa globalité et mener une approche comparative. Au cours de ma thèse, une étude en IRM de la morphologie des structures relatives aux processus sensoriels (olfactifs, auditifs,...) et aux processus socio-émotionnels (amygdale, hippocampe, substance grise périaqueducale,...) a donc été menée afin de tester les hypothèses concernant la sélection génétique, l’expérience précoce et la phylogénie. Pour tester l’hypothèse de la sélection génétique, nous avons utilisé deux lignées de caille japonaise, STI (Short Tonic Immobility) et LTI (Long Tonic Immobility), sélectionnées sur leur durée d’immobilité tonique, comportement adaptatif traduisant l’émotivité des individus. Nous avons montré que la sélection génétique influence la morphologie de régions cérébrales impliquées dans les processus émotionnels mais aussi sensoriels. Pour tester l’hypothèse de l’expérience précoce, nous avons étudié l’influence de l’exposition précoce à la musique en tant qu’enrichissement du milieu pour des agneaux en allaitement artificiel pour lesquels nous savons que les comportements adaptatifs sont altérés. Nous avons mis en évidence que cette expérience modifie le profil d’activité (notamment la réactivité émotionnelle), l’axe endocrinien et la morphologie cérébrale de certaines structures telles que le noyau caudé. Pour tester l’hypothèse de la phylogénie, une étude de biologie comparée a été menée sur différentes espèces sauvages (cerf-souris, maki catta, otarie…) au cours de laquelle nous avons décrit les spécificités morphologiques des structures cérébrales connues pour être impliquées dans les comportements adaptatifs.Ce travail de thèse montre donc l’implication de la sélection génétique, de l’expérience précoce mais aussi de la phylogénie dans la plasticité anatomique des régions associées aux comportements adaptatifs chez différentes espèces animales.

International audience; The fields of artificial intelligence and bio-inspired robotics have proven to cross several other fields of expertise including Cognitive Neuroscience. Here, we review principles of interaction between a natural (or artificial) organism and the environment where it lives. Then we ask whether such structural coupling shapes the way it behaves. For instance, how the sensory processing of the external world controls actions, and finally, behavior? We remind the main sources of inspiration for bio-inspired robotics and relate them to currently active fields of research like Embodiment and Enaction. These latter concepts are illustrated by examples of recent researches on two main aspects: (i) bio-inspired algorithms processing sensory signals coming from the outer world and (ii) bio-inspired controllers based on human behavior and physiology. Finally, we include an example of a bio-inspired robot controller design based on the concepts here exposed.

This thesis focuses on the human movement vigor, i.e., the speed spontaneously chosen by an individual to perform a voluntary action. The literature shows that vigor depends on an individual's implicit motiva-tion in the task and on a neural circuit involving the basal ganglia, as suggested by the bradykinesia of parkinsonian patients. Our initial work focused on the consistency of inter-individual differences of vigor and confirmed the trait-like aspect of vigor despite changes in tasks or effectors, with the ocu-lomotor system appearing to be apart (Study 1). Then, we wondered about the link between the vigor of each person and the perception of the vigor of others: if vigor is a key element of all our actions, it could also be a determining factor for interacting effectively with others, whether physically or socially. The mirror neuron system could play a role in the vigor of movement, both in action and in perception. In a second study, we have indeed shown the existence of a perceptual vigor law analogous to the motor law during a speed judgment task of biological movements. This judgment seems to be based on a general representation of the vigor of other people's movements rather than on the observer's own vigor (Study 2). This work opens theoretical perspectives but also perspectives of industrial applications (e.g., implementation of the general vigor law to a robot to optimize its interaction with the user) and clinical applications (e.g., rehabilitation of Parkinsonian patients)., Cette thèse s'intéresse à la vigueur du mouvement humain, c'est-à-dire la vitesse spontanément choisie par un individu pour réaliser une action volontaire. La vigueur dépend de la motivation implicite d'un individu dans la tâche et d'un circuit neuronal impli-quant les ganglions de la base, comme le suggère la bradykinésie des patients parkinsoniens. Nos pre-miers travaux se sont intéressés aux différences inter-individuelles de vigueur et ont confirmé que la vigueur est largement propre à un individu en dépit de changements de tâches ou d'effecteurs, le sys-tème oculomoteur semblant à part (Etude 1). Par la suite, nous nous sommes interrogés sur le lien entre la vigueur de chacun et la perception de la vigueur d'autrui : si la vigueur est un élément clé de toutes nos actions, elle pourrait également être détermi-nante pour interagir efficacement avec autrui, que ce soit physiquement ou socialement. Le système des neurones miroirs pourrait notamment jouer un rôle un rôle sur la vigueur du mouvement, aussi bien en action qu'en perception. Dans une seconde étude, nous avons effectivement montré l'existence d'une loi perceptive de vigueur ana-logue à la loi motrice au cours d'une tâche de jugement de vitesse de mouvements biologiques. Ce jugement semble basé sur une représentation générale de la vigueur des mouvements d'autrui plutôt que sur la vigueur propre de l'observateur (Etude 2). Ces travaux ouvrent des perspectives théoriques mais aussi des perspectives d'applications à la fois industrielles (e.g., implé-mentation de la loi de vigueur générale à un robot pour optimiser son interaction avec l'utilisateur) et cliniques (e.g., rééducation de patients parkinso-niens).

With its context-independent rules valid in any setting, mathematics is considered to be the champion of abstraction, and for a long time human mathematical reasoning was thought to follow nothing but the laws of logic. However, the idea that mathematics is grounded in nature has gained traction over the past decades, and the context-independency of mathematical reasoning has come to be questioned. The thesis we defend concerns the role played by general, non-mathematical knowledge on individuals’ understanding of numerical situations. We propose that what we count has a crucial impact on how we count, in the sense that humans' representation of numerical information is dependent on the semantic context in which it is embedded. More specifically, we argue that daily-life knowledge about the entities described in an arithmetic word problem can shape its interpretation and influence the strategy used to solve it, even among experts. We investigate this thesis using behavioral and physiological data collected among diverse populations, ranging from 2nd graders to expert mathematicians and math teachers. We discuss the general educational implications of these effects, and we propose new directions for future research on this crucial issue.