ASD-BARN

Autism Spectrum Disorders (ASD) are highly debilitating developmental syndromes which core feature is social and communications disorders. Motor skill impairments are frequently described in autism, but few studies have addressed the question of their origin and their specificity. Furthermore, it is not clear whether motor problems encountered in autism are related to dyspraxia, or if they present with specific features. This project aims at deciphering the origin of motor problems encountered by children who grow-up with autism in order to propose early interventions that could influence the other developmental trajectories, such as the social one. Our proposal aims at accurately identify the different levels of motor impairments seen in ASD and to compare their motor skills with those exhibited by Typically Developping (TD) children and children presenting with Developemental Coordination Disorder (DCD). We will use two different paradigms that separately assess: 1) the integrity of feed-back corrective mechanisms, 2) feed-forward control, and 3) the ability to build-up a sensori-motor representation. The « Grasp-to-Place task », will enable to determine and quantify the existence and the quality of the feed-forward programming and the on-line corrections using kinematics recordings. In this paradigm, subjects are required to reach for and grasp an object in order to displace it. This everyday life action will be performed on two objects of different weight (light and heavy objects) under two experimental conditions. In the first condition the subject will have a complete weight knowledge thus enabling him to adapt his motor program as a function of object weight (feed-forward execution). In the second condition, as participants will ignore object weight until they lifted the object they will have to adapt their movement to the object weight in flight (on-line execution). A more complex learning task, the « Bimanual load-lifting task », will test the on-line build-up of a sensori-motor representation by analysing kinematics and muscular (EMG) recordings. Most importantly, we will explore brain dynamics of motor learning processes by applying magnetoencephalography (MEG) during the Bimanual Load Lifting paradigm. Different motor processes namely: proprioceptive monitoring, use and update of a sensori-motor representation, anticipatory executive control will be correlated to brain oscillation modulation, both topographically and temporally. A last objective will be to identify differences between TD, ASD and DCD children and disambiguate if differences in pathological populations are due to a developmental delay in brain maturation or to altered brain functioning.