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Mental color imagery abilities are commonly measured using paradigms that involve naming, judging, or comparing the colors of visual mental images of well-known objects (e.g., “Is a sunflower darker yellow than a lemon”?). Although this approach is widely used in patient studies, differences in the ability to perform such color comparisons might simply reflect participants’ general knowledge of object colors rather than their ability to generate accurate visual mental images of the colors of the objects. The aim of the present study was to design a new color imagery paradigm. Participants were asked to visualize a color for 3 s and then to determine a visually presented color by pressing 1 of 6 keys. The authors reasoned that participants would react faster when the imagined and perceived colors were congruent than when they were incongruent. In Experiment 1, participants were slower in incongruent than congruent trials but only when they were instructed to visualize the colors. The results in Experiment 2 demonstrate that the congruency effect reported in Experiment 1 cannot be attributed to verbalization of the color that had to be visualized. Finally, in Experiment 3, the congruency effect evoked by mental imagery correlated with performance in a perceptual version of the task. The authors discuss these findings with respect to the mechanisms that underlie mental imagery and patients suffering from color imagery deficits.

The visual world around us is extremely complex and has a great deal of information embedded in various sources that compete for our attentional resources. Our cognitive system must select a limited amount of visual information, which allows one to adapt to the environment. The perceptive saliency of a piece of information automatically biases attentional resources towards it, and this process is often useful and adaptive. Nevertheless, when the advantaged information is not the most pertinent available, additional mental effort is necessary to suppress it and to select the information of interest. The purpose of this thesis is to connect models of attentional selection and inhibition to the global precedence effect. The latter describes the faster processing of the global structure of an object compared to its local constitutive parts as well as the interference from global to local level. This global precedence effect seems to exist in preschoolers, but appears to be sensitive to manipulations of saliency: when the local elements are dense, the global form spontaneously emerges and is prioritized; however, when local elements are sparse, they seem to be processed with priority. The main goal of this thesis is to specify the global/local development by 1) studying the attentional competition between global, intermediate and local hierarchical levels during development and 2) highlighting the central role of inhibitory control when selecting the less salient level. With a visual search task, we demonstrated that in adults the local level is always disadvantaged during the attentional competition for resources compared to more structural, global and intermediate, levels. Although children showed a similar pattern of results, the selection of the local level was impaired in 5- and 6-year-old children who committed more errors than older children and adults. This result indicates there is a lack of inhibition of the global form in preschoolers. With a negative priming paradigm, we validated the idea that adults and 7-year-old children need to inhibit the global hierarchical level (the most salient one) to select the local hierarchical level (the less salient one). However, when using sparse hierarchical figures, this pattern of results was reversed in 7-year-old children but not in adults. A local inhibition, instead of a global inhibition, seems to be necessary in children when processing sparse figures. Regardless of which level is the most salient at each age, the inhibition process appears necessary to suppress the information at the salient and non-pertinent level in order to select the less salient but most relevant information. Taken together, and with regards to models of attentional selection and inhibition and to dynamic theories of development, these results provide new interpretations and perspectives in the study of the global precedence effect in children and adults., Le monde visuel qui nous entoure est extrêmement complexe, constitué d'une grande quantité d'informations, toutes emboîtées les unes aux autres, qui entrent en compétition pour l'octroi de nos ressources attentionnelles. Notre système cognitif doit ainsi sélectionner un nombre limité d'informations qui lui permettront d'agir de façon adaptée sur son environnement. La saillance perceptive d'une information biaise automatiquement les ressources attentionnelles en sa faveur, un processus qui est la plupart du temps efficace et adaptatif. Néanmoins, lorsque l'information avantagée n'est pas celle qui est pertinente, un effort mental supplémentaire d'inhibition est nécessaire pour la supprimer et permettre la sélection de l'information d'intérêt. Cette thèse a pour objectif de faire le lien entre les modèles de sélection et d'inhibition attentionnelles et l'effet de précédence globale, c'est à dire le fait que la structure globale soit traitée plus rapidement que ses parties constituantes locales et interfère avec elles. Chez l'enfant d'âge préscolaire et scolaire, un tel effet de précédence globale semble exister précocement mais serait sensible à des manipulations de sa saillance : lorsque les éléments locaux sont denses, la forme globale émerge spontanément et est privilégiée. À l'inverse, lorsque les éléments locaux sont moins denses, ce sont eux qui semblent être traitées prioritairement. L'objectif de cette thèse est de préciser le développement du traitement global/local par 1) l'étude de la compétition attentionnelle entre les niveaux hiérarchiques global, intermédiaire et local au cours du développement et 2) la mise en évidence du rôle central du contrôle inhibiteur dans la sélection du niveau hiérarchique le moins saillant. Nous avons montré chez l'adulte, grâce à un paradigme de recherche visuelle, que le niveau local est toujours désavantagé durant la compétition attentionnelle par rapport aux niveaux structurels global et intermédiaire. Même si les enfants présentaient un pattern de résultats similaires, les enfants de 5 et 6 ans avaient des difficultés accrues dans la sélection locale, faisant davantage d'erreurs que les enfants plus âgés et les adultes. Ces résultats semblent indiquer un défaut d'inhibition de la structure globale chez les enfants d'âge préscolaire. Grâce à un paradigme d'amorçage négatif, nous avons vérifié que, chez l'adulte et l'enfant de 7 ans, la sélection du niveau local (peu saillant) nécessite bien l'inhibition du niveau global (le plus saillant). Toutefois, en utilisant des figures peu denses, une inversion de ce pattern de résultats était observée chez les enfants de 7 ans, résultat qui n'était pas observé chez les adultes. Une inhibition du niveau local, et non plus du niveau global, serait ainsi nécessaire chez l'enfant. Quel que soit le niveau le plus saillant à un âge donné, l'inhibition permettrait de supprimer l'information présente au niveau saillant et non-pertinent au profit de l'information d'intérêt moins saillante. L'ensemble de ces résultats, au regard des modèles actuels de sélection et d'inhibition attentionnelles et des théories dynamiques du développement, permet de nouvelles interprétations et perspectives dans l'étude de l'effet de précédence globale chez l'adulte et l'enfant.

International audience; Dual-process theories have suggested that emotion plays a key role in the framing effect in decision- making. However, little is known about the potential impact of a specific positive or negative emotional context on this bias. We investigated this question with adult participants using an emotional priming paradigm. First, participants were presented with positive or negative affective pictures (i.e., pleasant vs. unpleasant photographs). Afterward, participants had to perform a financial decision-making task that was unrelated to the pictures previously presented. The results revealed that the presentation framed in terms of gain or loss no longer affected subjects' decision-making following specific exposure to emotionally pleasant pictures. Interestingly, a positive emotional context did not globally influence risk-taking behavior but specifically decreased the risk propensity in the loss frame. This finding confirmed that a positive emotional context can reduce loss aversion, and it strongly reinforced the dual-process view that the framing effect stems from an affective heuristic belonging to intuitive System 1.

International audience; Background/AimEpidemiological studies reported that prenatal solvent exposure was associated with adverse neurobehavioral outcomes that suggest impaired motor inhibition function. Using functional Magnetic Resonance Imaging (fMRI) among children aged 10-12 years old, we aimed at investigating the effect of prenatal exposure to solvents on the activation of cerebral regions involved in the motor inhibition function.

Mental image scanning is generally assumed to be a single process that allows people to shift attention across visualized objects. However, this implicit assumption is open to question. We report a set of three experiments based on the tasks originally designed by Kosslyn, Ball, and Reiser (1978) and Finke and Pinker (1982). Participants scanned the identical images of an array of dots in the two tasks. Nevertheless, the participants required more time to shift their focus over the imaged stimulus in the Kosslyn et al. (1978) paradigm. Moreover, correlational analyses revealed no consistent relationship between the slopes of the increases in scanning times with increasing distances in the two paradigms. We conclude that in the Kosslyn et al. (1978) paradigm, the participants draw primarily on transformational processes to scan, whereas in the Finke and Pinker (1982) paradigm, they draw primarily on attentional processes. Both processes, transforming the image and shifting an attention window, produce linear increases in time with increases in distance, but for different reasons.

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International audience; Developmental studies using the Iowa Gambling Task (IGT) or child-friendly adaptations of the IGT converged in showing that children and adolescents exhibit a strong bias in favor of disadvantageous choices whereas adults learn to decide advantageously during the course of the task. In the present article, we reviewed developmental studies that used the IGT or child-friendly adaptations of the IGT to show how these findings provide a better understanding of the processes involved in decision-making under uncertainty. For instance, developmental studies have underlined that until late adolescence, the dominant strategy is to focus only on the frequency of punishment and to choose among options with infrequent losses. Indeed, school-aged children and adolescents' choices in the IGT seem to be guided by the loss frequency leading them to fail in distinguishing between advantageous and disadvantageous options. In addition, recent developmental studies revealed that adults switch less often after losses than school-aged children and adolescents. These findings suggest that psychological tolerance to loss may facilitate learning the characteristics of each option, which in turn improves the ability to choose advantageously. In conclusion, developmental studies help us refine our understanding of decision-making.

International audience; Neurodevelopmental disorders affect a substantial minority of the general population. Their origins are still largely unknown, but a complex interplay of genetic and environmental factors causing disturbances of the central nervous system's maturation and a variety of higher cognitive skills is presumed. Only limited research of rather small sample size and narrow scope has been conducted in neurodevelopmental disorders using a twin-differences design. The Roots of Autism and ADHD Twin Study in Sweden (RATSS) is an ongoing project targeting monozygotic twins discordant for categorical or dimensional autistic and inattentive/hyperactive-impulsive phenotypes as well as other neurodevelopmental disorders, and typically developing twin controls. Included pairs are 9 years of age or older, and comprehensively assessed for psychopathology, medical history, neuropsychology, and dysmorphology, as well as structural, functional, and molecular brain imaging. Specimens are collected for induced pluripotent (iPS) and neuroepithelial stem cells, genetic, gut bacteria, protein-/monoamine, and electron microscopy analyses. RATSS's objective is to generate a launch pad for novel surveys to understand the complexity of genotype-environment-phenotype interactions in autism spectrum disorder and attention-deficit hyperactivity disorder (ADHD). By October 2013, RATSS had collected data from 55 twin pairs, among them 10 monozygotic pairs discordant for autism spectrum disorder, seven for ADHD, and four for other neurodevelopmental disorders. This article describes the design, recruitment, data collection, measures, collected pairs' characteristics, as well as ongoing and planned analyses in RATSS. Potential gains of the study comprise the identification of environmentally mediated biomarkers, the emergence of candidates for drug development, translational modeling, and new leads for prevention of incapacitating outcomes.

Jean Piaget underestimated the cognitive capabilities of infants, preschoolers, and elementary schoolchildren, and overestimated the capabilities of adolescents and even adults which are often biased by illogical intuitions and overlearned strategies (i.e., “fast thinking” in Daniel Kahneman’s words). The crucial question is now to understand why, despite rich precocious knowledge about physical and mathematical principles observed over the last three decades in infants and young children, older children, adolescents and even adults are nevertheless so often bad reasoners. We propose that inhibition of less sophisticated solutions (or heuristics) by the prefrontal cortex is a domain-general executive ability that supports children’s conceptual insights associated with more advanced Piagetian stages, such as number-conservation and class inclusion. Moreover, this executive ability remains critical throughout the whole life and even adults may sometimes need “prefrontal pedagogy” in order to learn inhibiting intuitive heuristics (or biases) in deductive reasoning tasks. Here we highlight some of the discoveries from our lab in the field of cognitive development relying on two methodologies used for measuring inhibitory control: brain imaging and mental chronometry (i.e., the negative priming paradigm). We also show that this new approach opens an avenue for re-examining persistent errors in standard classroom-learning tasks.

Intuitions are often considered suboptimal because they can bias people's thinking. The bat-and-ball problem is a celebrated example of this potentially detrimental aspect of intuitions since it elicits a very appealing and prepotent intuitive but incorrect response. We propose to show that certain kinds of intuitions (i.e., prior beliefs) can help people to reason better on this task. In two experiments, participants answered either a classic congruent version of the bat-and-ball problem in which the intuitively cued response fitted with prior knowledge (i.e., was believable) or a modified incongruent version in which the intuitively cued response conflicted with prior knowledge (i.e., was unbelievable). Results indicate that participants who solved the modified unbelievable version performed better than participants who solved the classic believable version. Our data highlight that prior beliefs, even in the bat-and-ball problem, can accidentally make people perform better, probably because they encoura...

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International audience; Even if objectively presented with similar visual stimuli, children younger than 6 years of age exhibit a strong attraction to local visual information (e.g., the trees), whereas children older than 6 years of age, similar to adults, exhibit a visual bias toward global information (e.g., the forest). Here, we studied the cortical thickness changes that underlie this bias shift from local to global visual information. Two groups, matched for age, gender, and handedness, were formed from a total of 30 children who were 6 years old, and both groups performed a traditional global/local visual task. The first group presented a local visual bias, and the other group presented a global visual bias. The results indicated that, compared with the local visual bias group, children with a global visual bias exhibited (1) decreased cortical thickness in the bilateral occipital regions and (2) increased cortical thickness in the left frontoparietal regions. These findings constitute the first structural study that supports the view that both synaptic pruning (i.e., decreased cortical thickness) and expansion mechanisms (i.e., increased cortical thickness) cooccur to allow healthy children to develop a global perception of the visual world.

Cognitive success at school and later in life is supported by executive functions including cognitive control (CC). The pFC plays a major role in CC, particularly the dorsal part of ACC or midcingulate cortex. Genes, environment (including school curricula), and neuroplasticity affect CC. However, no study to date has investigated whether ACC sulcal pattern, a stable brain feature primarily determined in utero, influences CC efficiency in the early stages of cognitive and neural development. Using anatomical MRI and three-dimensional reconstruction of cortical folds, we investigated the effect that ACC sulcal pattern may have on the Stroop score, a classical behavioral index of CC efficiency, in 5-year-old preschoolers. We found higher CC efficiency, that is, lower Stroop interference scores for both RTs and error rates, in children with asymmetrical ACC sulcal pattern (i.e., different pattern in each hemisphere) compared with children with symmetrical pattern (i.e., same pattern in both hemispheres). Critically, ACC sulcal pattern had no effect on performance in the forward and backward digit span tasks suggesting that ACC sulcal pattern contributes to the executive ability to resolve conflicts but not to the ability to maintain and manipulate information in working memory. This finding provides the first evidence that preschoolers' CC efficiency is likely associated with ACC sulcal pattern, thereby suggesting that the brain shape could result in early constraints on human executive ability.

The present high-density event-related potential (ERP) study on 13 adults aimed to determine whether number conservation relies on the ability to inhibit the overlearned length-equals-number strategy and then imagine the shortening of the row that was lengthened. Participants performed the number-conservation task and, after the EEG session, the mental imagery task. In the number-conservation task, first two rows with the same number of tokens and the same length were presented on a computer screen (COV condition) and then, the tokens in one of the two rows were spread apart (INT condition). Participants were instructed to determine whether the two rows had an identical number of tokens. In the mental imagery task, two rows with different lengths but the same number of tokens were presented and participants were instructed to imagine the tokens in the longer row aligning with the tokens in the shorter row. In the number-conservation task, we found that the amplitudes of the centro-parietal N2 and fronto-central P3 were higher in the INT than in the COV conditions. In addition, the differences in response times between the two conditions were correlated with the differences in the amplitudes of the fronto-central P3. In light of previous results reported on the number-conservation task in adults, the present results suggest that inhibition might be necessary to succeed the number-conservation task in adults even when the transformation of the length of one of the row is displayed. Finally, we also reported correlations between the speed at which participants could imagine the shortening of one of the row in the mental imagery task, the speed at which participants could determine that the two rows had the same number of tokens after the tokens in one of the row were spread apart and the latency of the late positive parietal component in the number-conservation task. Therefore, performing the number-conservation task might involve mental transformation processes in adults.

Research on moral judgement traditionally deals with scenarios involving trade-offs between saving lives and causing harm or death. In the field of moral psychology and philosophy, these specific scenarios are regularly used jointly, regardless of the severity of harm. We predicted that the confounding between distinct phrasings involving different degrees of harm will have an impact on the frequency of utilitarian judgements regardless of the mere moral value of the action (as usually investigated in the moral judgement field). In line with this prediction, a first experiment showed that utilitarian responses were less frequent for conflicting moral scenarios that involved death, as compared to scenarios that involved non-lethal harm. A second experiment showed that participants' utilitarian responses decreased as the severity of harm increased. Experimental studies on moral reasoning should take greater care to avoid potential confounds associated with this content factor.

In four experiments, we explored the capacity for spatial mental imagery in patients with hippocampal lesions, using tasks that minimized the role of learning and memory. On all four tasks, patients with hippocampal lesions performed as well as controls. Nonetheless, in separate tests, the patients were impaired at remembering the materials that had been used to assess mental imagery. The findings suggest that the hippocampus is not needed for constructing many forms of spatial imagery but is needed for the formation of long-term memory. In future studies of the neural organization of spatial mental imagery, it will be important to separate the contribution of spatial processing from the contribution of learning and memory.

Objectives. We explain why traits of interest to behavioral scientists may have a genetic architecture featuring hundreds or thousands of loci with tiny individual effects rather than a few with large effects and why such an architecture makes it difficult to find robust associations between traits and genes. Methods. We conducted a genome-wide association study at 2 sites, Harvard University and Union College, measuring more than 100 physical and behavioral traits with a sample size typical of candidate gene studies. We evaluated predictions that alleles with large effect sizes would be rare and most traits of interest to social science are likely characterized by a lack of strong directional selection. We also carried out a theoretical analysis of the genetic architecture of traits based on R.A. Fisher’s geometric model of natural selection and empirical analyses of the effects of selection bias and phenotype measurement stability on the results of genetic association studies. Results. Although we replicated several known genetic associations with physical traits, we found only 2 associations with behavioral traits that met the nominal genome-wide significance threshold, indicating that physical and behavioral traits are mainly affected by numerous genes with small effects. Conclusions. The challenge for social science genomics is the likelihood that genes are connected to behavioral variation by lengthy, nonlinear, interactive causal chains, and unraveling these chains requires allying with personal genomics to take advantage of the potential for large sample sizes as well as continuing with traditional epidemiological studies.

Solving simple arithmetic word problems is a major ability that children must acquire throughout the primary-grade mathematics curriculum. However, this skill is often challenging for them. For instance, “unknown referent problems” are more difficult to solve than “unknown compare problems.” In unknown compare problems, the relational term (e.g., “more than”) is consistent with the arithmetic operation (e.g., addition) required to find the solution, whereas in unknown referent problems, the relational term (e.g., “more than”) is inconsistent with the arithmetic operation (i.e., subtraction). To determine whether solving unknown referent problems relies on the ability to inhibit the heuristic “add if more, subtract if less” strategy, we devised a negative priming (NP) paradigm for children, adolescents, and adults. For each test trial, an unknown referent problem served as a prime, in which the inhibition of the heuristic strategy was necessary and was immediately followed by an unknown compare problem that served as a probe, in which the heuristic strategy became the appropriate strategy to use. For each control trial, a neutral problem served as a prime and was followed by an unknown compare problem as a probe. All participants performed the unknown compare problems more slowly when they were preceded by unknown referent problems, which reflected typical NP effects. Our results confirm that success in completing unknown referent problems reveals not only participants’ ability to grasp the underlying logic of the problem but also their ability to inhibit a misleading strategy. This study sheds light on the importance of inhibitory control in learning mathematics.

International audience; Are individual differences in numerical performance sustained by variations in gray matter volume in schoolchildren? To our knowledge, this challenging question for neuroeducation has not yet been investigated in typical development. We used the Voxel-Based Morphom-etry method to search for possible structural brain differences between two groups of 10-year-old schoolchildren (N = 22) whose performance differed only in numerical transcod-ing between analog and symbolic systems. The results indicated that children with low numerical proficiency have less gray matter volume in the parietal (particularly in the left intraparietal sulcus and the bilateral angular gyri) and occipito-temporal areas. All the identified regions have previously been shown to be functionally involved in transcoding between analog and symbolic numerical systems. Our data contribute to a better understanding of the intertwined relationships between mathematics learning and brain structure in healthy schoolchildren.

Previous studies have demonstrated that the brief presentation of a fearful face improves not only low-level visual processing such as contrast and orientation sensitivity but also improves visuospatial processing. In the present study, we investigated whether fear improves mental rotation efficiency (i.e., the mental rotation rate) because of the effect of fear on the sensitivity of magnocellular neurons. We asked 2 groups of participants to perform a mental rotation task with either low-pass or high-pass filtered 3-dimensional objects. Following the presentation of a fearful face, participants mentally rotated objects faster compared with when a neutral face was presented but only for low-pass filtered objects. The results suggest that fear improves mental rotation efficiency by increasing sensitivity to motion-related visual information within the magnocellular pathway.

International audience; Visual perception depends on the integration of local elements of a visual scene into a global frame. Evidence from behavioral studies shows that (1) the detection of the global frame is faster than the detection of the local parts, a phenomenon called the global advantage, and that (2) an interference of the global shape is also present during local processing. Together, these effects are called the global precedence effect (GPE). Even if the global advantage appears to impact neural processing as early as the first 100 ms post-stimulus, previous studies failed to find a global interference effect before 200 ms post-stimulus. Using for the first time a rapid display of letter component stimuli during a global/local selective task in which conditions with perceptual conflict, congruent and incongruent conditions were considered, the present event-related potential (ERP) study shows a global interference effect occurring as early as the time range of the N1 component. In particular, only congruent stimuli elicited similar N1 amplitude during the global and local tasks, whereas an increased of the N1 amplitude during the global task was observed (as compared to the local task) for both stimuli with perceptual conflict and incongruent stimuli. This finding corroborates the recent neural models of human visual perception.

International audience; Neuroeducation aims to improve pedagogical approaches by adding neuroimaging data. Practical and technical challenges emerge when children undergo magnetic resonance imaging (MRI), thereby raising several problems. We performed a meta-analysis of functional MRI datasets that were published during 1995 to 2011 according to the type of training of 4001 typically developing children and adolescents. The meta-analysis investigated whether different types of training (standard, mock, coaching trainings) improved the success rate of functional MRI inclusion rate and decreased the exclusion rate for excessive motion. We wondered if these specific trainings have differential developmental effects. Additionally, we examined if certain factors, such as age, the type of the cognitive tasks, the sex ratio, the financial compensation, the session order with structural MRI and the duration of the functional runs would influence the functional MRI success rate (more inclusion and less exclusion). The results indicated that coaching training for all of the children is the most relevant type of training to reduce motion and include more data. The type of task also took part in the success rate for fMRI. We propose guidelines to optimize the inclusion rate of functional MRI studies with typically developing children. Finally, we offer clinical and educational implications. Leroux, Lubin, Houdé, and Lanoë How to best train children and adolescents for fMRI?

International audience; Neuroeducation aims to improve pedagogical approaches by adding neuroimaging data. Practical and technical challenges emerge when children undergo magnetic resonance imaging (MRI), thereby raising several problems. We performed a meta-analysis of functional MRI datasets that were published during 1995 to 2011 according to the type of training of 4001 typically developing children and adolescents. The meta-analysis investigated whether different types of training (standard, mock, coaching trainings) improved the success rate of functional MRI inclusion rate and decreased the exclusion rate for excessive motion. We wondered if these specific trainings have differential developmental effects. Additionally, we examined if certain factors, such as age, the type of the cognitive tasks, the sex ratio, the financial compensation, the session order with structural MRI and the duration of the functional runs would influence the functional MRI success rate (more inclusion and less exclusion). The results indicated that coaching training for all of the children is the most relevant type of training to reduce motion and include more data. The type of task also took part in the success rate for fMRI. We propose guidelines to optimize the inclusion rate of functional MRI studies with typically developing children. Finally, we offer clinical and educational implications. Leroux, Lubin, Houdé, and Lanoë How to best train children and adolescents for fMRI?

The general goal of this thesis was to study (i) the influence of different socio-emotional contexts on decision-making under risk, in children, adolescents and adults and (ii) the developmental dynamics of the Types 1 (heuristic) and 2 (analytic) of reasoning within the framework of the Dual Process theories, and their articulation with the Prospect Theory. According to us, a better articulation between these two theories could account more efficiently of the influence of emotions on reward and punishment sensitivity in decision-making. Therefore, we first examined the influence of an incidental emotional context on the framing effect - a classical bias in decision-making - on adult participants. We started by studying the influence of the valence of the emotions (positive or negative) and then the influence of different specific emotions (anger and fear) on this bias. Our results revealed that the participants were no longer affected by the framing effect following an exposure to a positive emotional context, due to a decrease of risk aversion in the loss frame. The two negative emotions we considered had opposite effects on risk taking: fear tended to increase risk taking, whereas anger tended to decrease it. In a follow-up study, we investigated the influence of incidental positive emotions on the framing effect during adolescence, a critical period for risk taking. In adolescents, the framing effect was modulated by the amount of the outcome at stake, and the emotional context had different impact on this bias depending of the amount of the outcome considered. Then, we examined the development of two integral (and counterfactual) emotions, regret and relief, and how these emotions affect our willingness to reconsider a choice. We elaborated a new gambling task and we manipulated the outcome obtained by the participants to induce regret or relief. This study provided evidence that the ability to experience regret and relief and the ability to take them into consideration continue to develop during late childhood and adolescence. We finally studied the development of social regret and relief from late childhood to adulthood, using a situation of social competition (playing against a playmate). This socio-emotional context seems to bias the rational evaluation of regret and relief in adolescence, as some situations are evaluated as more desirable, as compared to the same situations in a context of individual game. These results are discussed in light of the Prospect theory, as reward and punishment sensitivity seems to be differently modulated by socio-emotional context, at each developmental stage., L’objectif général de cette thèse est (i) d’examiner l’influence du contexte socio-émotionnel sur la prise de décision à risque, chez l’enfant, l’adolescent et l’adulte (ii) et de s’interroger sur la dynamique développementale des Types 1 (heuristique) et 2 (analytique) de raisonnement envisagés par les théories du double processus et de leur articulation avec la Prospect Theory. Selon nous, cette articulation permettra de mieux rendre compte de l’influence des émotions sur la sensibilité aux gains et aux pertes dans la prise de décision. Dans ce contexte, nous avons d’abord examiné l’influence d’un contexte émotionnel incident sur la sensibilité à un biais décisionnel classique, l’effet du cadre de présentation, chez l’adulte. Nous nous sommes intéressés à l’influence du contexte émotionnel du point de vue de sa valence (positive ou négative), avant d’étudier l’influence d’émotions spécifiques (la colère et la peur). Sur le plan de la valence, nos résultats mettent en évidence l’influence des émotions positives dans la disparition de l’effet du cadre, à travers la réduction de l’aversion aux pertes. Les émotions plus spécifiques ont une influence différenciée sur la prise de risque, la peur tendant à l’augmenter, tandis que la colère tend à la réduire. Puis, nous avons étudié l’influence d’émotions positives sur la sensibilité à l’effet du cadre à l’adolescence, période critique en termes de prise de risque. La sensibilité à l’effet du cadre varie en fonction des sommes en jeu, ce qui conduit à une influence différenciée du contexte émotionnel selon cet enjeu. Nous nous sommes ensuite intéressés au développement de deux émotions intégrales au processus de prise de décision, dites également contrefactuelles (le regret et le soulagement) et à leur influence sur la volonté de reconsidérer un choix. Pour ce faire, nous avons élaboré une tâche de prise de décision induisant du regret ou du soulagement et nous avons mis en évidence un développement progressif du ressenti de ces émotions et de la capacité à les prendre en compte lors de la reconsidération d’un choix antérieur. Enfin, nous avons étudié le développement du regret social et du soulagement social de l’enfance à l’âge adulte, à travers un paradigme de compétition avec un pair. Le contexte de compétition semble biaiser l’évaluation rationnelle du regret et du soulagement à l’adolescence, certaines situations étant perçues comme plus désirables par rapport à un contexte de jeu individuel. Ces résultats sont discutés en lien avec la Prospect Theory, puisque la sensibilité aux gains et aux pertes semble modulée de façon distincte, à différents stades du développement, par le contexte émotionnel.

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Although few studies have systematically investigated the relationship between visual mental imagery and visual working memory, work on the effects of passive visual interference has generally demonstrated a dissociation between the two functions. In four experiments, we investigated a possible commonality between the two functions: We asked whether both rely on depictive representations. Participants judged the visual properties of letters using visual mental images or pictures of unfamiliar letters stored in short-term memory. Participants performed both tasks with two different types of interference: sequences of unstructured visual masks (consisting of randomly changing white and black dots) or sequences of structured visual masks (consisting of fragments of letters). The structured visual noise contained elements of depictive representations (i.e., shape fragments arrayed in space), and hence should interfere with stored depictive representations; the unstructured visual noise did not contain such elements, and thus should not interfere as much with such stored representations. Participants did in fact make more errors in both tasks with sequences of structured visual masks. Various controls converged in demonstrating that in both tasks participants used representations that depicted the shapes of the letters. These findings not only constrain theories of visual mental imagery and visual working memory, but also have direct implications for why some studies have failed to find that dynamic visual noise interferes with visual working memory.

Learning with discriminative methods is generally based on minimizing themisclassification of training samples, which may be unsuitable for imbalanceddatasets where the recognition might be biased in favor of the most numerousclass. This problem can be addressed with a generative approach, which typicallyrequires more parameters to be determined leading to reduced performances inhigh dimension. In such situations, dimension reduction becomes a crucial issue.We propose a feature selection / classification algorithm based on generativemethods in order to predict the clinical status of a highly imbalanced datasetmade of PET scans of forty-five low-functioning children with autism spectrumdisorders (ASD) and thirteen non-ASD low-functioning children. ASDs aretypically characterized by impaired social interaction, narrow interests, andrepetitive behaviours, with a high variability in expression and severity. Thenumerous findings revealed by brain imaging studies suggest that ASD isassociated with a complex and distributed pattern of abnormalities that makesthe identification of a shared and common neuroimaging profile a difficult task.In this context, our goal is to identify the rest functional brain imagingabnormalities pattern associated with ASD and to validate its efficiency inindividual classification. The proposed feature selection algorithm detected acharacteristic pattern in the ASD group that included a hypoperfusion in theright Superior Temporal Sulcus (STS) and a hyperperfusion in the contralateralpostcentral area. Our algorithm allowed for a significantly accurate (88\%),sensitive (91\%) and specific (77\%) prediction of clinical category. For thisimbalanced dataset, with only 13 control scans, the proposed generativealgorithm outperformed other state-of-the-art discriminant methods. The highpredictive power of the characteristic pattern, which has been automaticallyidentified on whole brains without any priors, confirms previous findingsconcerning the role of STS in ASD. This work offers exciting possibilities forearly autism detection and/or the evaluation of treatment response in individualpatients.

Traditionally, characterizations of the macrolevel functional organization of the human cerebral cortex have focused on the left and right cerebral hemispheres. However, the idea of left brain versus right brain functions has been shown to be an oversimplification. We argue here that a top-bottom divide, rather than a left-right divide, is a more fruitful way to organize human cortical brain functions. However, current characterizations of the functions of the dorsal (top) and ventral (bottom) systems have rested on dichotomies, namely where versus what and how versus what. We propose that characterizing information-processing systems leads to a better macrolevel organization of cortical function; specifically, we hypothesize that the dorsal system is driven by expectations and processes sequences, relations, and movement, whereas the ventral system categorizes stimuli in parallel, focuses on individual events, and processes object properties (such as shape in vision and pitch in audition). To test this hypothesis, we reviewed over 100 relevant studies in the human neuroimaging and neuropsychological literatures and coded them relative to 11 variables, some of which characterized our hypothesis and some of which characterized the previous dichotomies. The results of forward stepwise logistic regressions supported our characterization of the 2 systems and showed that this model predicted the empirical findings better than either the traditional dichotomies or a left-right difference.

When participants take part in mental imagery experiments, are they using their "tacit knowledge" of perception to mimic what they believe should occur in the corresponding perceptual task? Two experiments were conducted to examine whether such an account can be applied to mental imagery in general. These experiments both examined tasks that required participants to "mentally rotate" stimuli. In Experiment 1, instructions led participants to believe that they could reorient shapes in one step or avoid reorienting the shapes altogether. Regardless of instruction type, response times increased linearly with increasing rotation angles. In Experiment 2, participants first observed novel objects rotating at different speeds, and then performed a mental rotation task with those objects. The speed of perceptually demonstrated rotation did not affect the speed of mental rotation. We argue that tacit knowledge cannot explain mental imagery results in general, and that in particular the mental rotation effect reflects the nature of the underlying internal representation and processes that transform it, rather than participants' pre-existing knowledge.

International audience; Background: A real-world visual scene consists of local elements (e.g. trees) that are arranged coherently into a global configuration (e.g. a forest). Children show psychological evolution from a preference for local visual information to an adult-like preference for global visual information, with the transition in visual preference occurring around 6 years of age. The brain regions involved in this shift in visual preference have not been described. Methods and Results: We used voxel-based morphometry (VBM) to study children during this developmental window to investigate changes in gray matter that underlie the shift from a bias for local to global visual information. Six-year-old children were assigned to groups according to their judgment on a global/local task. The first group included children who still presented with local visual processing biases, and the second group included children who showed global visual processing biases. VBM results indicated that compared to children with local visual processing biases, children with global visual processing biases had a loss of gray matter in the right occipital and parietal visuospatial areas. Conclusions: These anatomical findings are in agreement with previous findings in children with neurodevelopmental disorders and represent the first structural identification of brain regions that allow healthy children to develop a global perception of the visual world.

In this article, we report a new image-scanning paradigm that allowed us to measure objectively individual differences in spatial mental imagery—specifically, imagery for location. Participants were asked to determine whether an arrow was pointing at a dot using a visual mental image of an array of dots. The degree of precision required to discriminate “yes” from “no” trials was varied. In Experiment 1, the time to scan increasing distances, as well as the number of errors, increased when greater precision was required to make a judgement. The results in Experiment 2 replicated those results while controlling for possible biases. When greater precision is required, the accuracy of the spatial image becomes increasingly important—and hence the effect of precision in the task reflects the accuracy of the image. In Experiment 3, this measure was shown to be related to scores on the Paper Folding test, on the Paper Form Board test, and on the visuospatial items on Raven's Advanced Progressive Matrices—but not to scores on questionnaires measuring object–based mental imagery. Thus, we provide evidence that classical standardized spatial tests rely on spatial mental imagery but not object mental imagery.

In two experiments, we used a temporal integration task to investigate visual mental images based on information in short-term memory or generated from information stored in long-term memory (LTM). We specifically asked whether the two sorts of images rely on depictive representations. If mental images rely on depictive representations, then it should be possible to combine mental images and visual percepts into a single representation that preserves the spatial layout of the display. To demonstrate this, participants were asked to generate mental images and then combine them with visual percepts of grids that were partially filled with different numbers of dots. Participants were asked to determine which cell remained empty when the two grids were combined. We contrasted predictions of propositional or verbal description theories with those of depictive theories, and report findings that support the claim that mental images—based on either short-term or LTM—depict information.

Emotions have been shown to modulate low-level visual processing of simple stimuli. In this study, we investigate whether emotions only modulate processing of visual representations created from direct visual inputs or whether they also modulate representations that underlie visual mental images. Our results demonstrate that when participants visualize or look at the global shape of written words ( low-spatial-frequency visual information), the prior brief presentation of fearful faces enhances processing, whereas when participants visualize or look at details of written words ( high-spatial-frequency visual information), the prior brief presentation of fearful faces impairs processing. This study demonstrates that emotions have similar effects on low-level processing of visual percepts and of internal representations created on the basis of information stored in long-term memory.

Two types of representations can be used to specify spatial relations: Coordinate spatial relations representations specify the precise distance between two objects, whereas categorical spatial relations representations assign a category (such as above or below) to specify a spatial relation between two objects. Computer simulation models suggest that coordinate spatial relations representations should be easier to encode if one attends to a relatively large region of space, whereas categorical spatial relations should be easier to encode if one attends to a relatively small region of space. We tested these predictions. To vary the scope of attention, we asked participants to focus on the local or global level of Navon letters, and immediately afterwards had them decide whether a dot was within 2.54 cm of a bar (coordinate judgment) or was above or below the bar (categorical judgment). Participants were faster in the coordinate task after they had just focused on the global level of a Navon letter whereas they were faster in the categorical task after they had just focused on the local level. Although we did not test the hemispheric lateralization of these effects, these findings have direct implications for theories of why the cerebral hemispheres differ in their relative ease of encoding the two kinds of spatial relations.

Previous studies have provided evidence of interference due to a language-default mode (i.e., the singular/plural opposition) in 2-year-old children when solving arithmetic problems using a traditional onlooker method. However, an action-based method could help to bypass this language bias. In particular, when an arithmetic problem is presented to the children by the experimenter (onlooker mode) or realized by the children themselves (actor mode), performances are better with the latter. Thus, an experimental procedure based on “math in action” allows a brain-and-mind shift from a global language-bias (singular/plural) strategy to an exact numerical strategy. In this framework, we examined whether the exact numerical strategy induced by the actor method remains operational when children had to subsequently solve the same arithmetic problem using the traditional onlooker method. Results from 112 children suggest that this pedagogical effect of action bypasses the interference from language in onlooker mode after an initial confrontation of the problem in actor mode. This enduring embodiment effect has important implications for cognitive and preschool assessment in toddlers.

Our previous studies provide some evidence of between-language effects on arithmetic performance in 2-year-olds. French-speaking children were especially biased by the use of the word un as a cardinal value and as an article in the singular/plural opposition (1 vs. the set 2, 3, …). Here we evaluated the ability of a new action-based assessment method to avoid this bias. A total of 80 French-speaking 2- and 3-year-olds were confronted with impossible (1 + 1 = 1 or 1 + 1 = 3) and possible (1 + 1 = 2) addition problems that triggered the bias. The problems were either presented to the children by the experimenter (onlooker mode) or realized by themselves (actor mode). The 2-year-olds performed better in the actor mode than in the onlooker mode. A subtraction control with no language ambiguity (2–1 = 2 or 1) was conducted with 80 other children; both modes elicited comparable performances regardless of age. These data indicate that the actor mode is effective for assessing arithmetic ability in French-speaking 2-year-olds.

The research reported in the present article investigates whether information is represented the same way in both visual mental imagery and the early phases of visual perception. In Experiment 1, the same participants scanned over patterns of dots in a mental image (with images based on a just-seen pattern), during perception, and in an iconic image. The time to scan increasing distances increased at comparable rates in the three tasks. However, in Experiment 2, when mental images were created from information stored in long-term memory, participants scanned more slowly in the mental image condition. Nevertheless, the rates of scanning in the perceptual tasks were highly correlated with the rates of scanning in the imagery tasks in both experiments. The results provide evidence that mental images and perceived stimuli are represented similarly and can be processed in the same way.

The "Global Precedence Effect" (GPE) is a well-established phenomenon characterised by a global advantage (global response times that are faster than local response times) and an interference effect from global distractors during identification of local targets but not vice versa. In the present study, two experiments were carried out to examine how the GPE is affected by the meaningfulness of the stimuli. Using global/local compound stimuli based on either meaningful or meaningless stimuli, we found, on the one hand, that the global level was always processed faster than the local level, irrespective of the meaningfulness of the material. On the other hand, results show that the interference effect occurred only with meaningful stimuli. We propose that automatic identification of meaningful stimuli plays a role in the interference effect. These results suggest that the GPE involves both "sensory mechanisms" (responsible for the global advantage) and "cognitive mechanisms" (responsible for the interference effect).

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.

International audience; Although the functional brain network involved in reading for adults and children is now well documented, a critical lack of knowledge still exists about the structural development of these brain areas. To provide a better overview of the structural dynamics of the brain that sustain reading acquisition, we acquired anatomical MRI brain images from 55 children that were divided into two groups: one prior to the formal learning of reading (n = 33, 5-6 years old) and the second a few years after formal learning (n = 22, 9-10 years old). Reading performances were collected based on the ''Alouette-R'' test, a standardized test for reading text in French. Voxel-based morphometry analysis of gray matter showed that only the right insula volume was different between the two groups. Moreover, the reading group showed that the volumes of the left fusiform gyrus (corresponding to the well-known visual word form area, VWFA), the anterior part of the left inferior occipital gyrus and the left thalamus were significantly modulated by reading performance. This study reinforces the crucial role of the Visual Word Form Area in reading and correlation analyses performed between ROIs volumes suggesting that the VWFA is fully connected with the traditional left-hemispheric language brain network.

International audience

We present an extension of the Individual Brain Charting dataset –a high spatial-resolution, multi-task, functional Magnetic Resonance Imaging dataset, intended to support the investigation on the functional principles governing cognition in the human brain. The concomitant data acquisition from the same 12 participants, in the same environment, allows to obtain in the long run finer cognitive topographies, free from inter-subject and inter-site variability. This second release provides more data from psychological domains present in the first release, and also yields data featuring new ones. It includes tasks on e.g. mental time travel, reward, theory-of-mind, pain, numerosity, self-reference effect and speech recognition. In total, 13 tasks with 86 contrasts were added to the dataset and 63 new components were included in the cognitive description of the ensuing contrasts. As the dataset becomes larger, the collection of the corresponding topographies becomes more comprehensive, leading to better brain-atlasing frameworks. This dataset is an open-access facility; raw data and derivatives are publicly available in neuroimaging repositories., Measurement(s) functional brain measurement • regional part of brain • brain measurement • cognition Technology Type(s) functional magnetic resonance imaging Factor Type(s) type of task Sample Characteristic - Organism Homo sapiens Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12958181

International audience; Ce chapitre fait un état des lieux des recherches mettant en évidence le rôle adaptatif des processus émotionnel dans les apprentissages en situation de prise de décision, de l’enfance à l’âge adulte. Ce chapitre vise également à mieux comprendre le rôle des processus émotionnels en lien avec une augmentation, ou une diminution, de la prise de risque à l’adolescence.

International audience

International audience; The study of local cortical folding patterns showed links with psychiatric illnesses as well as cognitive functions. Despite the tools now available to visualize cortical folds in 3D, manually classifying local sulcal patterns is a timeconsuming and tedious task. In fact, 3D visualization of folds helps experts to identify different sulcal patterns but fold variability is so high that the distinction between these patterns sometimes requires the definition of complex criteria, making manual classification difficult and not reliable. However, the assessment of the impact of these patterns on the functional organization of the cortex could benefit from the study of large databases, especially when studying rare patterns. In this paper, several algorithms for the automatic classification of fold patterns are proposed to allow morphological studies to be extended and confirmed on such large databases. Three methods are proposed, the first based on a Support Vector Machine (SVM) classifier, the second on the Scoring by Non-local Image Patch Estimator (SNIPE) approach and the third based on a 3D Convolution Neural Network (CNN). These methods are generic enough to be applicable to a wide range of folding patterns. They are tested on two types of patterns for which there is currently no method to automatically identify them: the Anterior Cingulate Cortex (ACC) patterns and the Power Button Sign (PBS). The two ACC patterns are almost equally present whereas PBS is a particularly rare pattern in the general population. The three models proposed achieve balanced accuracies of approximately 80% for ACC patterns classification and 60% for PBS classification. The CNN-based model is more interesting for the classification of ACC patterns thanks to its rapid execution. However, SVM and SNIPE-based models are more effective in managing unbalanced problems such as PBS recognition.