4 research outputs found
Utilisation de lâĂ©lectrophysiologie dans lâĂ©tude du dĂ©veloppement des capacitĂ©s dâintĂ©gration audiovisuelle du nourrisson Ă lâĂąge adulte
Une littĂ©rature abondante documente les bĂ©nĂ©fices de lâintĂ©gration multisensorielle chez les adultes ainsi que les mĂ©canismes cĂ©rĂ©braux sous-jacents Ă ces habiletĂ©s. Toutefois, de nombreuses questions sur le dĂ©veloppement de lâintĂ©gration multisensorielle chez lâenfant demeurent sans rĂ©ponse et les travaux chez les animaux ainsi que les donnĂ©es comportementales, Ă©lectrophysiologiques et en neuroimagerie chez lâhomme ne forment pas de consensus quant Ă son caractĂšre innĂ© ou acquis. Le premier objectif de la prĂ©sente thĂšse vise donc Ă recenser les Ă©crits de la littĂ©rature sur le dĂ©veloppement des capacitĂ©s dâintĂ©gration multisensorielle. Cette revue de la littĂ©rature, qui constituera lâarticle 1 de la thĂšse, prĂ©sente les Ă©tudes comportementales et neuronales en faveur du caractĂšre innĂ© ou acquis des processus dâintĂ©gration multisensorielle. Lâarticle 1 suggĂšre que certaines habiletĂ©s de traitement multisensoriel sont prĂ©sentes chez le nourrisson et le jeune enfant, mais que la capacitĂ© Ă intĂ©grer les informations multisensorielles de façon optimale demeure un long processus qui se dĂ©veloppe tardivement au cours de lâenfance et de lâadolescence. Cette revue nous a Ă©galement permis de mieux cibler les lacunes de la littĂ©rature relatives au dĂ©veloppement neuronal des capacitĂ©s dâintĂ©gration, avec une attention particuliĂšre sur lâintĂ©gration dâinformations audiovisuelles non linguistiques. Ainsi, aucune Ă©tude en Ă©lectrophysiologie ne sâest encore penchĂ©e sur la progression dĂ©veloppementale des capacitĂ©s dâintĂ©gration audiovisuelle chez les nourrissons et les enfants dâĂąge prĂ©scolaire. Ce constat a justifiĂ© la tenue de lâĂ©tude expĂ©rimentale prĂ©sentĂ©e Ă lâarticle 2 dont lâobjectif vise Ă caractĂ©riser la progression dĂ©veloppementale neurotypique des mĂ©canismes dâintĂ©gration dâinformations audiovisuelles non linguistiques dĂšs lâĂąge de 3 mois jusquâĂ lâĂąge adulte. Cette recherche vise Ă©galement Ă confirmer l'Ăąge oĂč les mĂ©canismes dâintĂ©gration audiovisuelle, dâune part, commencent Ă fonctionner de façon similaire aux adultes et, dâautre part, atteignent leur pleine maturitĂ©. Pour ce faire, nous avons menĂ© une Ă©tude expĂ©rimentale transversale sur un vaste Ă©chantillon composĂ© de 121 participants neurotypiques en utilisant lâĂ©lectrophysiologie Ă haute densitĂ©, plus sĂ©cifiquement par le biais dâanalyses temps-frĂ©quence. Notre Ă©tude dĂ©montre la prĂ©sence de prĂ©curseurs de lâintĂ©gration audiovisuelle dĂšs lâĂąge de 2 ans. De plus, nous observons que les jeunes de 11-14 ans commencent Ă intĂ©grer ces informations de façon similaire aux adultes, mais que les mĂ©canismes dâintĂ©gration audiovisuelle atteignent leur pleine maturitĂ© tardivement au cours de lâadolescence soit entre les Ăąges de 15 et 17 ans. Cette Ă©tude appuie la littĂ©rature quant Ă lâĂ©mergence progressive des capacitĂ©s Ă intĂ©grer les informations audiovisuelles, permet de documenter la progression dĂ©veloppementale de ces capacitĂ©s et rĂ©pond Ă lâabsence de littĂ©rature sur les processus neuronaux de lâintĂ©gration audiovisuelle chez le nourrisson et lâenfant dâĂąge prĂ©scolaire. Dans lâensemble, cette thĂšse offre une meilleure comprĂ©hension du dĂ©veloppement neurotypique des mĂ©canismes dâintĂ©gration audiovisuelle et fournit un point de comparaison pour Ă©tudier ces processus auprĂšs dâenfants prĂ©sentant des troubles neurodĂ©veloppementaux souvent accompagnĂ©s de dĂ©ficits sensoriels.An abundant litterature documents the benefits associated to multisensory integration in adults as well as brain mechanisms underlying these skills. However, numerous questions regarding the development of multisensory integration during childhood remain unanswered and there is no consensus among animal data in addition to behavioral, electrophysiological and neuroimaging studies conducted in humans wether these skills are innate or acquired. The first objective of this thesis is to review the literature on the development of multisensory integration capacities. This review, which will constitute the first article of this thesis, presents neuronal and behavioral studies in favour of the nature or nurture character of multisensory integration mechanisms. This review suggests that the capacity to detect and form multisensory associations begins very early in development, but that the ability to integrate multisensory information in an optimal manner is a progressive process that continues to develop over childhood and adolescence. This work has also allowed us to better target the gaps in the existing literature related to the neuronal development of integration capacities, with special emphasis on the integration of non linguistic audiovisual information.
Thus, to date no electrophysiological study has yet address the developmental progression of audiovisual integration capacities in infants and preschool children. This ascertainment has justified the conduct of the experimental study presented in the second article with the aim of characterizing the neurotypical developmental progression of non linguistic audiovisual information integration mecanisms as early as 3 months of age to adulthood. This research is also aimed at confirming the age when audiovisual integration mechanisms, on the one hand, begin to operate in a similar fashion than adults and, on the other hand, reach their full maturity. For these purposes, we have conducted an experimental
iv
study. Here, we undertook a cross-sectional experimental investigation on a large cohort of 121 neurotypical individuals using high-density electrophysiology more specifically through time-frequency analysis. Our study revealed the presence of precursors of audiovisual integration in children as young as two years of age. Moreover, our results indicate that 11- to 14-year-old adolescents start to integrate this information in an adult-like manner, but that audiovisual integration mechanisms reach their full maturity late throughout adolescence between the age of 15 and 17 years. This study supports the literature regarding the progressive emergence of the capacities to integrate audiovisual information, documents the developmental progression of these capacities and answers the absence of literature on the neuronal processes of audiovisual integration in infants and preschool children.
Overall, this thesis provides a better understanding of the development of audiovisual integration mechanisms and provides a benchmark to investigate these processes in children with neurodevelopmental disorders often accompanied with sensory impairments
The influence of contour fragmentation on recognition memory: An event-related potential study
The Bank of Standardized Stimuli (BOSS), a New Set of 480 Normative Photos of Objects to Be Used as Visual Stimuli in Cognitive Research
There are currently stimuli with published norms available to study several psychological aspects of language and visual cognitions. Norms represent valuable information that can be used as experimental variables or systematically controlled to limit their potential influence on another experimental manipulation. The present work proposes 480 photo stimuli that have been normalized for name, category, familiarity, visual complexity, object agreement, viewpoint agreement, and manipulability. Stimuli are also available in grayscale, blurred, scrambled, and line-drawn version. This set of objects, the Bank Of Standardized Stimuli (BOSS), was created specifically to meet the needs of scientists in cognition, vision and psycholinguistics who work with photo stimuli