There is an extensive debate in the adult literature on whether recognition memory can better be explained by a single- or a dual-process account. Single-process accounts assume that a single memory strength signal underlies recognition. Dual-process accounts propose two independent processes, namely recollection (slow and associated with contextual details) and familiarity (fast and automatic). The aim of this dissertation was to advance this debate using a cognitive developmental approach. By investigating age-related changes of recognition memory across childhood as a function of theoretically motivated experimental manipulations, predictions drawn from single- and dual-process models of recognition memory were tested. We adapted the Process Dissociation Paradigm (PDP; Jacoby, 1991) to disentangle processes underlying recognition memory in 5-, 7-, and 11-year-olds and adults using a Dual-Process Signal Detection cognitive modelling approach (DPSD; Yonelinas, 1996). Experiments 1 – 6 demonstrated that 5-year-olds are able to recollect items based on perceptual details. Consistent with dual-process theory, across all age groups a response time limit decreased recollection while leaving familiarity unaffected (Chapter 2). Converging evidence consistent with dissociations during childhood was found after repeated item presentation (Chapter 3). Finally, after a thorough empirical validation of our approach, the new paradigm was used to investigate the developmental perceptual to semantic shift (Chapter 4). These findings, using a double dissociation logic, have advanced the theoretical debate on the nature of recognition memory by showing that one process is insufficient to account for the developmental and experimental findings reported here. Recollection and familiarity follow different developmental trajectories and are affected by encoding and retrieval manipulations (i.e., repetition and time limits). This provides a challenge for existing theories of recognition memory.

Si les enjeux du placement familial à titre permanent dans le cadre de l’Aide Sociale à l’Enfance concernent évidemment en tout premier lieu les enfants déplacés d’une famille à l’autre, l’accueil constitue néanmoins un événement particulier au regard du système familial et plus encore des enfants accueillants. Notre travail de recherche vise à mieux saisir la singularité des expériences fraternelles susceptibles de se tisser entre enfants (« accueillants » et « accueillis »), au-delà des configurations relationnelles traditionnellement issues de la filiation. Plus précisément, dans la mesure où le cadre du placement s’institue à la croisée des sphères familiales et professionnelles, nous cherchons à comprendre comment ces expériences fraternelles sont « habitées » par les dimensions du travail et de là, comment l’enfant accueillant, devenu adolescent, vit ce dispositif d’accueil familial. Divers types de données (quantitatives et qualitatives) ont été recueillies auprès de 45 adolescents accueillants âgés de 11 à 18 ans. Dans une perspective de triangulation, nous avons articulé un traitement statistique des questionnaires, une analyse lexico-métrique de l’intégralité de notre corpus et enfin une analyse qualitative de contenu de quatre entretiens. Même si les enfants accueillants manifestent des scores moyens d’anxiété et de dépression inférieurs à ceux de la population du même âge, nos résultats montrent qu’accueillir chez soi un enfant en placement constitue une expérience de vie complexe, notamment de par les remaniements relationnels, familiaux et personnels qu’elle requiert. La manière dont les enfants accueillants parlent leur expérience montre clairement l’existence d’une dynamique singulière de socialisation professionnelle, mais aussi un certain enlisement dans l’éprouvé brut d’une relation marquée par des difficultés, ainsi qu’une mise en tension des appartenances familiales. Finalement, nous mettons en évidence deux postures et conceptions de l’accueil opposées, selon que les enfants pensent et vivent le rapport à l’enfant accueilli dans une perspective de care ou de prestation de services / If the foster care concerns at first foster children displaced from a family to another, it constitutes a singular event for the entire family but mainly for children of foster parents. Our research aims to understand the particularity of these potential fraternal experiences between children (fostered and fostering), beyond the traditional relational configurations derived from filiation. Specifically, to the extent that the foster care is instituted at the intersection of work and family spheres, we seek to understand how these fraternal experiences are invested by the dimensions of work and then how child of foster parents, as a teenager, lives the foster care system. Various types of data (quantitative and qualitative) were collected from 45 teenagers aged from 11 to 18 years. From the perspective of triangulation, we have articulated a statistical analysis of questionnaires, a lexical metric analysis of our entire corpus and finally a qualitative content analysis of four interviews. Even if children of foster parents present anxiety and depression scores lower than the population of the same age, our results show that receiving a child in foster care at home is a complex life experience, changing relational, family and personal balances. How fostering children speak their experience clearly shows the existence of a singular dynamic professional socialization, but also a certain risk of feeling overwhelmed with relationship problems and contrasting family memberships. Finally, we highlight two postures and opposing conceptions of foster care, as children think and live the relationship with the foster child from a perspective of care or service delivery

Cette thèse a cherché à évaluer et à comprendre les répercussions des maltraitances physiques et psychiques sur le développement des enfants qui en sont victimes. Il s’agit ici de repérer l’influence des représentations de la mère concernant l’enfant qui ont conduit aux actes maltraitants. Le but de l’étude était de repérer la place de l’enfant dans les enjeux psychiques maternels avec l’hypothèse de la mise en acte d’un fantasme d’infanticide à l’œuvre. Dans une approche culturelle, il a été question d’élargir la notion de maltraitance au-delà des syndromes communs notamment les enfants singuliers. L’étude a visé à comprendre les modalités d’expression de l’enfant de moins de 3 ans à travers les comportements d’externalisation et d’internalisation. 15 enfants de 6 mois à 3 ans et leur mère ont été recrutés. Différentes méthodes ont été utilisées, l’échelle de Brunet-Lézine-Révisé et la Malette Projective Petite Enfance, l’observation et l’entretien clinique à visée de recherche. Les résultats ont fait ressortir la mise en acte de fantasme chez les 12 mères sous différentes formes à travers le vécu de la grossesse, de l’accouchement, du maternage etc. et les effets des maltraitances qui entravent le développement de ces enfants. / The goal of this research is to evaluate and understand the repercussions of physical and psychological abuse on the development of children who are victims. The focal point is to identify the mental appraisal the mother has of the child and how it inherently drives her to mistreat the child. The aim of the study was to ascertain the child’s place in the mother’s mental thoughts with the assumption of the portrayal of an infanticide fantasy at work. Culturally, it was pertinent to broaden the notion of abuse way beyond the common syndromes especially associated with children that act bizarre. The study aimed to understand the modalities of expression of the child below the age of three through behaviors externally and internally expressed. Fifteen children from 6 months to 3 years of age and their mothers were selected for this study. Different methods were used such as, the revised version of the Brunet-Lézine scale, the "Malette projective Petite enfance " test, observation and clinical research interviews. The results highlighted the act of fantasy in the 12 mothers in different forms. Right from the experience of pregnancy, to childbirth, to nursing the child, etc. and the effects of abuse that hinder the development of these children.

Pour percevoir le monde qui nous entoure, nous effectuons des mouvements rapides des yeux afin de placer les objets d'intérêt en fovéa, région de l'oeil où l'acuité visuelle est maximale. Ces mouvements oculaires, appelés saccades, sont précis malgré leur rapidité d'exécution. Le mécanisme assurant leur précision tout au long de la vie est l'adaptation saccadique. L'adaptation saccadique peut être facilement induite en laboratoire grâce au paradigme non invasif de double saut de la cible (McLaughlin, 1967) qui simule une « imprécision » de la visée d'une cible en déplaçant celle-ci pendant la saccade de manière répétée. Le système saccadique corrige progressivement l'erreur de visée induite artificiellement, la saccade amenant directement l'oeil vers la nouvelle position de la cible après seulement une cinquantaine d'essais. A ce jour, si les paramètres saccadiques (latence, amplitude, durée, vitesse moyenne et pic de vitesse) sont très bien documentés chez l'adulte, ils restent peu décrits chez le très jeune enfant. De plus, aucune étude n'a examiné la plasticité du système saccadique chez les enfants de moins de huit ans. Le but de ce travail de thèse est double. Il vise d'une part à caractériser les paramètres saccadiques chez le très jeune enfant. Pour ce faire, les mouvements oculaires d'un groupe de 115 bébés âgés de 7 à 42 mois ont été enregistrés pendant 140 essais (Etude 2). Nous avons mis au point un protocole expérimental original adapté à l'âge de ces jeunes participants que nous avons préalablement validé chez des adultes (Etude 1). D'autre part, nous avons étudié si la plasticité du système oculomoteur des bébés de cet âge possède les mêmes caractéristiques que celle des adultes en induisant, grâce au paradigme de double saut de la cible, une adaptation en diminution d'amplitude (Etude 3) et une adaptation en augmentation d'amplitude de la saccade (Etude 4). Les résultats reposant sur plus d'une centaine de saccades consécutives par participant montrent que les bébés sont capables de sélectionner un stimulus visuel comme cible et d'effectuer une saccade oculaire vers celle-ci. Le système oculomoteur est cependant immature à cet âge puisque les saccades des bébés ont des latences plus longues et sont plus hypométriques, i.e. moins précises que celles des adultes. Cependant, les performances saccadique des bébés s'améliorent avec l'âge pour la latence et, contre toute attente, au fur et à mesure des essais pour la précision de leur visée. Par ailleurs, les modifications adaptatives en réponse au saut intra-saccadique de la cible sont présentes chez un plus grand nombre d'adultes que d'enfants en diminution d'amplitude et inversement en augmentation d'amplitude. Cependant, l'efficacité de l'adaptation saccadique est similaire chez les deux groupes de participants. Nos études contribuent à la compréhension du développement du contrôle oculomoteur : le déclenchement de la saccade devient plus rapide (latence) avec l'âge mais la forte hypométrie de la saccade reste la même entre 7 et 42 mois. De façon inattendue, la précision saccadique s'améliore au cours de la session expérimentale suggérant une capacité d'apprentissage à court terme (Etude 2). Dans les Etudes 3 et 4, la plasticité du système oculomoteur est révélée pour la première fois chez des enfants d'âge préscolaire, signant des mécanismes adaptatifs fonctionnels chez le jeune enfant qui ne leur permettent cependant pas d'obtenir la précision saccadique des adultes. / To perceive the world around us, we perform rapid eye movements to bring objects of interest into the fovea, the eye region where visual acuity is optimal. These eye movements, called saccades, are accurate despite their high velocity. The mechanism that ensures accuracy throughout life is called saccadic adaptation. Saccadic adaptation can be easily induced in the laboratory by using the noninvasive double-step target paradigm (McLaughlin, 1967) that simulates targeting errors of the saccade by displacing repeatedly the target during the saccade. The saccadic system progressively reduces the error induced artificially so that after only fifty trials, the eyes rech the new position of the target. Today, if saccadic parameters (latency, amplitude, duration, average velocity and peak velocity) are well documented in adults, they remain poorly described in the very young children. Moreover, no study has examined the plasticity of the saccadic system in children aged under eight years-old. The goal of this thesis is twofold. On the one hand, it aims at characterizing saccadic parameters in very young children. To do this, the eye movements of a group of 115 babies aged 7-42 months-old were recorded during 140 trials (Study 2). We developed an original experimental protocol adapted to the age of these young participants, which first validated in adults (Study 1). One the other hand, we investigated whether the plasticity of the babies' oculomotor system has the same characteristics as adults' by inducing an adaptive shortening of saccade amplitude (backward adaptation; Study 3) and an adaptive lengthening of saccade amplitude (forward adaptation; Study 4). The results based on more than a hundred consecutive saccades per participant show that babies are able to select a stimulus as a visual target and generate a saccade toward it. However, the oculomotor system is immature at this age because babies' saccades have longer latencies and are more hypometric, i.e. less accurate than saccades in adults. Nevertheless, saccade latency improves with age in the child group. Unexpectedly, saccade accuracy improves over trials. Furthermore, adaptive changes in response to the intra-saccadic target step are present in a larger number of adults than children for backward adaptation and conversely for forward adaptation. However, the efficiency of saccadic adaptation is similar in the two groups of participants. Our studies allow to better understanding the development of oculomotor control: saccades are initiated faster with age but the high saccade hypometria remains the same between the age of 7 and 42 months. Unexpectedly, saccade accuracy improves over the course of the experimental session suggesting a short-term learning ability (Study 2). In Studies 3 and 4, the plasticity of the oculomotor system is revealed for the first time in preschool children. These results suggest that adaptive mechanisms are functional in young children. This ability however does not allow them to be as accurate as adults.

Chez des enfants ayant une épilepsie sévère et une lésion cérébrale étendue, l'ablation fonctionnelle d'un hémisphère représente le traitement le plus efficace. Cette thèse a pour objet les aspects pragmatiques et émotionnels du langage chez 40 enfants ayant bénéficié d'une hémisphérotomie afin d'étudier le développement du langage sur le versant pragmatique et de la compréhension émotionnelle et de mieux comprendre le profil socio-cognitif en fonction du côté opéré et de l'âge de la chirurgie eu égard au concept de spécialisation hémisphérique et de la plasticité cognitive développementale. Nos résultats montrent des troubles de la pragmatique du langage dans 40% des cas. Ces troubles sont notamment observés chez les sujets opérés d'hémisphérotomie droite après l'âge de 18 mois et indépendamment de la compréhension lexicale ou grammaticale du langage. Une corrélation a été mise en évidence entre les troubles de la pragmatique et les fonctions exécutives. Des déficits de reconnaissance des émotions faciales sont également observés dans cette population. Enfin, une longue durée de l'épilepsie et un âge tardif à la chirurgie altèrent la qualité de la compréhension émotionnelle à partir de récits et renforce l'idée qu'une chirurgie précoce améliore le pronostic langagier et socio-cognitif. / Children with medically refractory epilepsy caused by extensive hemispheric lesions are the best candidate for hemispherotomy in order to cure epilepsy. It leads the patient to the amazing situation of living with the one controlateral isolated and safe hemisphere. The topic of this research concerns pragmatic and emotional aspects of language in a large population of 40 hemispherotomized children. Our aim was to study development of language, peculiarly pragmatic skills and emotion comprehension, and analyse their socio-cognitive profile according to side and age at surgery, considering hemispheric specialization and developmental cognitive plasticity. Pragmatic disorders were found in 40% of patients. More frequent pragmatic disorders were observed after right hemispherotomy among children operated after the age of 18 months, independently of lexical or syntactic comprehension. We demonstrated a correlation between pragmatic language impairment and deficits in executive functions. We showed a long term deficit in facial emotion recognition abilities in this population. Finally, the longer was the duration of epilepsy and the later was the surgery, the worst was their emotion comprehension of stories, promoting early surgery to improve their linguistic and socio-cognitive development.

Recent research suggests that visual-verbal paired associate learning (PAL) taps a crossmodal associative learning mechanism involved in reading acquisition. However, evidence from children with dyslexia indicates that deficits in visual-verbal PAL are strongly linked to the verbal demands of the task. The research presented in this thesis had two overarching aims: first, to dissociate crossmodal and verbal demands in driving the PAL-reading relationship, and second, to assess the hypothesis that visual-verbal PAL plays a causal role in reading development. To address the first aim, a series of experiments examined the relationship between reading ability and PAL tasks differing in modality (crossmodal, unimodal) and output demand (visual, verbal). The results supported a verbal account of the PAL-reading relationship. In typically developing children and children with dyslexia, only tasks with a verbal output demand (i.e., visual-verbal PAL, verbal-verbal PAL) demonstrated a relationship with reading ability. In children with dyslexia, poor performance was isolated to difficulties learning novel phonological forms, rather than difficulties specific to crossmodal associative learning. Furthermore, the ability to learn novel phonological forms was found to fully explain visual-verbal PAL performance across reading abilities. In a final experiment, the causal role of visual-verbal PAL in reading development was assessed. The results of a longitudinal study from the start to the end of kindergarten showed that visual-verbal PAL measured in pre-readers did not predict reading ability at the end of kindergarten. Instead, PAL performance was influenced by learning to read.

The current research explored the thesis that cognitive self-recognition might have an executive function in 3- and 4-year-olds. Although it is well established that children recognise themselves in mirrors by the end of infancy, the cognitive and behavioural impact of this capacity has yet to be elucidated. Experiments 1 to 6 showed that preschool children could form and maintain a cognitive link between the self and external stimuli, as a result of which, self-referent stimuli were given mnemonic priority. Experiments 4 to 8 indicated that in tasks involving self-recognition, 3- and 4-year-olds’ ability to process other-referent stimuli was compromised by self-focus. Finally, Experiments 9 and 10 demonstrated that mirror self-recognition increased preschoolers’ tendency to self-regulate, leading them to behave in line with socially accepted standards. Together, these experiments provide novel evidence to confirm that cognitive self-recognition has a role in preschoolers’ performance on tasks requiring memory, attention, inhibition, and planning. This implies that when salient, the self may become the ultimate executer of behaviour. By observing 3- and 4-year-olds’ differential processing of self- and other-referent stimuli we infer the existence of a functionally active, self-reflective agent. Moreover, the role of the self is temporally extended, influencing children’s cognition and behaviour in the past (Experiment 1 to 3), present (Experiments 4 to 8) and future (Experiments 9 to 10). This implies that preschool children may have developed the foundations necessary to build the experience of personal identity.

Research suggests that children are only able to flexibly apply more than one label (e.g. mouse and animal) in one situation with one conversational partner after they pass standard false belief tasks. Both abilities have been attributed to the understanding of perspective. The aim of the studies was to extend previous research to examine the disambiguation effect, children’s tendency to select an unfamiliar object in the presence of another but familiar object as referent for a novel word. Theoretical considerations suggest this effect initially results from a lack of understanding perspective. Five studies were conducted in Scotland and Austria, involving 243 children between the ages of 2.5 and 6.5. Studies 1 to 3 compared the standard disambiguation task with a task in which a strong pragmatic cue indicates the familiar object is the correct referent. Performances on these tasks were compared with performances on the false belief task, the alternative naming task, as well as tests of executive functioning. Studies 4 and 5 extended these methods to examine bilingual children’s metacognitive abilities in relation to word learning. Children become able to suspend the disambiguation effect when presented with strong pragmatic cues at the same time as they pass false belief and alternative naming tasks (Experiment 1). This can neither be attributed to impulsivity or the ability to inhibit a response, nor order effects of pragmatic cues and novel words (Experiment 2). Children’s ability to apply two labels to one object in a correction task also related to their perspectival understanding. Previous findings that suggested that younger children could produce multiple labels in a misnaming paradigm were not replicated (Experiment 3 a, b). The developmental change in children’s metalinguistic behaviour was demonstrated to follow the same trajectory in monolinguals, bilinguals and children exposed to another language (Experiment 4 and 5). Bilinguals show a marginally better ability to recall novel foreign language labels. The disambiguation effect is the result of cognitive immaturity in young children. Older children show a change in behaviour at the same time as they present more metacognitive maturity. Common development with theory of mind and metalinguistic abilities is attributed to an understanding of perspective.

Child and adolescent mood and anxiety symptoms are common and debilitating, with long-term effects on well-being. Research presented in this thesis examines interpersonal cognitive factors in the emergence of anxious and depressive symptoms in late childhood through to early adulthood. The thesis considers this issue using three main approaches. For the first, data are presented showing that biases in the appraisals of social situations are the aspects of interpersonal cognition most closely associated with emotional symptoms. For the second, longitudinal twin data are used to examine genetic and environmental origins of these interpersonal cognitive biases and their temporal prediction of symptoms across a 2-year period. Data show that interpersonal cognitive factors are strongly influenced by non-shared environmental factors, and moreover, predict symptoms across time. The final section of the thesis comprises four studies using Cognitive Bias Modification of Interpretations (CBM-I) training methodology to show that both positive and negative interpretive biases for interpersonal information can be induced in adolescents. Positive biases are shown to persist for at least 24 hours after training, and induced positive and negative biases are shown to differentially predict anxious responses to an experimental stressor. Evidence is also provided to suggest that effects following training positive interpretive biases may transfer to other cognitive measures, namely appraisals of ambiguous emotional faces. Finally, data tentatively show that CBM-I training may be useful in reducing negative interpretations of interpersonal information made by 11-year-old children undergoing the transition to secondary school. In summary, studies in this thesis support the contribution of cognitive biases to mood and anxiety symptoms in childhood and adolescence. They further extend this knowledge by suggesting that these reflect individual-specific (non-shared) environmental risks to predict symptoms across time. These biases may also be amenable to change through training interventions, with some - albeit weak - effects on other cognitive outcomes.

Cette thèse investigue l'apprentissage implicite d'une grammaire artificielle chez l'enfant avec et sans retard mental à travers le rôle des propriétés de surface du matériel (répétitions adjacentes ou non-adjacentes) et l'influence des instructions en phase test (tests de génération implicite ou explicite). Un des objectifs est de départager quatre des principaux modèles de l'apprentissage implicite en examinant la sensibilité aux propriétés de surface saillantes du matériel présenté à des enfants d'âges différents. La robustesse des capacités d'apprentissage implicite face au développement et au niveau intellectuel est également testée en rapport avec la perméabilité des instructions en phase test aux influences explicites. Enfin, ces travaux étudient l'appréhension des stimuli d'entraînement et l'adaptation comportementale progressive en fonction de l'âge des sujets et des caractéristiques perceptives et statistiques du matériel. Les résultats révèlent une sensibilité aux propriétés de surface spécifiques aux séquences d'entraînement plutôt qu'à la structure grammaticale à partir de laquelle elles ont été construites. Les Expériences 1 et 3 montrent que l'apprentissage est invariant face à l'âge et au niveau intellectuel lorsque les consignes limitent les contaminations explicites. En revanche, malgré une phase d'apprentissage identique aux Expériences 1 et 3, les Expériences 2 et 4 indiquent l'émergence d'effets d'âge et une altération des performances chez les enfants présentant un retard mental, lorsque les instructions délivrées en test sollicitent des processus intentionnels de récupération de l'information. L'Expérience 5 montre que différents types de saillances (perceptive, positionnelle et statistique) guident l'appréhension du matériel lors de la phase d'étude et ce, de manière concurrentielle, avant de conduire à la formation progressive d'unités plus complexes. Cette thèse apporte des éléments en faveur d'un apprentissage spécifique des stimuli, basé sur le traitement attentionnel de leurs propriétés de surface et la mise en œuvre de mécanismes associatifs de base. Elle confirme également les postulats de robustesse propres aux processus implicites et précise les précautions méthodologiques nécessaires à l'étude des capacités d'apprentissage implicite, telles que la neutralité des procédures aux influences explicites ou l'emploi d'un groupe contrôle. / This thesis investigates artificial grammar implicit learning in mentally retarded and typically developing children through the role of the surface features (adjacent or non-adjacent repetitions) of the material and the influence of test instructions (implicit or explicit generation tests). One of the aims is to differentiate between four of the main implicit learning models by examining the sensitivity to the perceptually salient features of the material presented to children of different ages. The robustness of implicit learning capacities in the face of development and intellectual level is equally tested according to the permeability of the test instructions to explicit influences. Finally, these experiments study the apprehension of the training stimuli and the progressive behavioural adaptation as a function of the age of the participants and the perceptual and statistical characteristics of the material. The results reveal sensitivity to the specific surface features of the training sequences rather than to the grammatical structure from which they were built. On the one hand, Experiments 1 and 3 show that implicit learning is invariant with age and intellectual level when the test instructions limit the explicit contaminations. On the other hand, despite the same training phase used in Experiments 1 and 3, Experiments 2 and 4 indicate age effects and a performance impairment in children with mental retardation, when the test instructions elicit intentional information retrieval processes. Experiment 5 shows that different types of saliencies (perceptual, positional and statistical) guide the apprehension of the material during the training phase operating concurrently, before leading to the progressive formation of more complex units. This thesis brings elements in favour of a stimuli-specific learning, based on the attentional processing of their surface features and the involvement of basic associative mechanisms. It also confirms the postulates of robustness of implicit processes and states the methodological precautions that are necessary to the study of implicit learning capacities, such as the neutrality of the procedures to explicit influences or the use of a control group.