Thesis defences: Marie Pieron (IJN)

Marie Pieron (IJN)

Le 30 septembre 2013 à partir de 14h en Salle des Actes.
École normale supérieure, 45, rue d’Ulm 75005 Paris 

"L'inhibition de retour saccadique dans les troubles du spectre autistique".

Le jury sera composé de :

Tiziana ZALLA, Chercheur, CNRS, Directrice de thèse
Jean-Louis ADRIEN, Professeur, Université Paris Descartes, Rapporteur
Sylvie CHOKRON, Directrice de recherche, CNRS, Université Paris Descartes, Rapporteur
Jean-Yves BAUDOUIN, Maître de conférence, Université de Bourgogne, Examinateur
Christine DERUELLE, Directrice de recherche, CNRS, Université Aix-Marseille, Examinatrice
Ann LOHOF, Professeur, Université Pierre et Marie Curie, Examinatrice


Abstract:

In autism spectrum disorders (ASD), visual perception is atypical both in terms of low-level perceptual surfunctioning and perceptual deficits for high-level operations. This phenomenon induces consequences on the triad of symptoms found in ASD: impairments in communication and social interactions and restricted/repetitive behaviour. In order to explore the relationship between oculomotor system, attention, visual perception and this triad, I have worked on the saccadic inhibition of return (IOR), a low-level visual phenomenon.
First, I studied the time course of saccadic IOR. Results of this study showed earlier saccadic IOR effect in autistic individuals compared to typically developed individuals (TD). Indeed, saccadic IOR occurred for a stimulus onset asynchrony shorter in autistic individuals while it occurred later in TD individuals. These findings reflect a visual search that is more oriented toward novelty in the visual environment in autistic individuals. This is an advantage in visual search tasks, in which autistic individuals showed better performance and could be considered as one of the attention mechanisms underlying these performances.
Secondarily I analysed the influence of directional change of gaze on the IOR. The results showed that saccadic IOR effect is present in both TD and autistic groups.
All together these results showed that the saccadic IOR effect is present in individuals with ASD, with both non-social and social peripheral cues.