Ces travaux ont pour but d'explorer le traitement musical chez les personnes présentant un trouble du spectre autistique (TSA). Cette question a été abordée sous l'angle des traitements global et local dans le cadre des deux théories cognitives dominantes de l'autisme : i) la faiblesse de cohérence centrale et ii) la théorie du surfonctionnement perceptif. Ces deux théories postulent la présence d'un biais de traitement envers l'information locale dans l'autisme provenant, soit i) d'un déficit du traitement global, soit ii) d'une capacité perceptive supérieure. A travers une dizaine d'études, nous avons confronté ces deux théories manipulant les traitements global et local dans la musique. Nous avons aussi questionné la perception auditive chez ces personnes ainsi que son impact sur des traitements de plus haut niveau. Dans l'ensemble, nos travaux mettent en évidence une plus grande implication des processus perceptifs dans le traitement musical chez ces personnes, allant dans le sens de la théorie du surfonctionnement perceptif. Par ailleurs, certains de nos résultats pointent un mécanisme cognitif central chez les personnes autistes : le mécanisme de cartographie véridique. / This research aimed to explore musical processing in individuals with an autistic spectrum disorder. This question has been tackled by exploring global and local processing in the framework of the two main cognitive theories of autism: i) the weak central coherence theory and ii) the enhanced perceptual processing theory. These two theories postulate a bias toward local processing in autism which originates either from i) a global processing deficit or ii) enhanced perceptual capacities. Through ten studies, we confronted these two theories by manipulating global and local processing of music. We also explored auditory perception in autistic people and its impact on higher musical processing. Globally, our research highlights a greater implication of perceptual processes in musical processing, giving support to the enhanced perceptual processing theory. In addition, some of our results point to a central cognitive mechanism in autism: the mechanism of veridical mapping.

<p>Three main theories have been proposed to account for the completion of occluded objects, namely local theories (e.g., Kellman & Shipley, 1991), global theories (e.g., Boselie & Leeuwenberg, 1986), and integrative models of completion (e.g., Sekuler, 1994; van Lier et al., 1994). Here, we investigated age-related changes in the completion of a complex partially occluded object using a prime-matching task. Subjects were shown a prime (global, local, occluded, or no prime) that was followed immediately by two shapes that were judged as being the same or different. In Experiment 1, we tested adults (n = 36/group) at various prime durations (150 - 700 msec) to tap into earlier and later representations of the occluded object. Although the occluded object primed both the global and local shapes at 150 and 500 msec (<em>p</em>s<0.05), only the global shapes were primed at 300 and 700 msec (<em>p</em>s<0.05). Overall, our results are most consistent with integrative models of completion. In Experiment 2, we tested 8-year-olds (n = 20) at a prime duration of 700 msec and 11-year-olds (n = 30/group) at a prime duration of 300 or 700 msec. For 11-year-olds, unlike adults, the occluded object did not significantly prime either the global or local shapes at 300 msec (<em>p</em>>0.50). For both 8- and 11-year-olds, the global, local, and occluded primes did not significantly prime either shape at 700 msec (<em>p</em>s>0.50). Based on the current testing conditions, we found that the perceptual completion process may not be adult-like even at 11 years of age.</p> / Master of Science (MSc)