Action understanding and imitation of actions with an inferable functional outcome level (IFOL) in young children with autism spectrum disorders

Background: Converging evidence from EEG and fMRI studies in adults and school-aged children with autism spectrum disorders(ASD) has led some to propose that autism results from a failure of the mirror neuron system(MNS). However, only studies of young children with ASD can determine whether this dysfunction ia s primary or a secondary deficit. The understanding and imitation of actions with an inferable functional outcome level (IFOL) are critical in social interaction and praxis learning. To the best of our knowledge this kind of actions are not yet investigated in young children with ASD. Objectives: To examine action understanding and imitation of actions with IFOL in children with ASD compared to typically developing(TD) peers. Methods: participants: 20 children with ASD(full IQ above 85) and 20 age and gender matched TD between 2 and 2,5 years of age. pre- and post-tests: observation of the child's grip (bimanual versus unimanual)while drinking a glass of juice to determine the child's predominantly grip and to investigate the correlation between action understanding and implicite imitative learning. The ability to perceive and predict action goals based on the unimanual grip selection of the demonstrator will be investigated by videos shown on a computer screen. Gaze position will be measured with a corneal reflection technique (Seeing Machine FaceLab). The target video will show the demonstrator who performs two different goal-directed actions with IFOL: grasping a glass to drink versus grasping a glass to place. We shall compare the gaze position of ASD and TD. We shall also compare children who selected predominantly a bimanual grip to grasp a glass(without motor familiarity with the observed unimanual grips) with children who selected predominantly an unimanual grip(with motor familiarity)to investigate the effect of congruency between the observed action and the child's motor repertoire on the ability to predict goals. If the child's gaze reaches the goal(mouth or second glass)at the same time or after the demonstrator's hand reaches the goal then the gaze shift is labelled reactive. In contrast, if the child's gaze reaches the goal before the demonstrator's hand reaches the goal then the gaze shift is labelled predictive. We assume that if the predictive gaze appears in the reaching stage(i.e. before the demonstrator grasps the glass) the child has tracked the grip type to understand the action goal, which may be an indication of activity of the MNS. In contrast, if the predictive gaze shifting appears in the placing stage the child has tracked the direction of the moving hand. We expect that regardless of diagnosis and level of motor familiarity, all children initially will use direction of motion as stimulus to predict the demonstrator's goal. Moreover, we expect that ASD children, in contrast to TD children, will not use grip type as stimulus after some trials. A control video with geometric figures will be used to rule out that logical reasoning construes goal prediction.

Jaar van publicatie:2012

Toegankelijkheid:Closed