This thesis aimed to provide an insight into, and account for, the varying levels and patterns of ability across different tests of inhibition in autism. In order to address the effects of the meaningful word stimuli of the classic Stroop task on inhibitory performance of children with autism, Experiment I explored reasons for the unique inhibitory strengths of children with autism on the classic Stroop task. The remainder of the thesis focused on tests of inhibition which do not use meaningful word stimuli and explored potential reasons why these tasks still give rise to conflicting results. A comprehensive investigation of motor versus cognitive inhibition in children with autism, the impact of presentation style and working memory load on inhibitory performance, and the impact of same and different response sets was conducted in Experiments 2-4. Furthermore, the possibility of differential impairment in prepotent response inhibition and resistance to distractor inhibition, including the role of a possible bias to weak central coherence in children with autism on the flanker task, was investigated in the final Experiments 5 and 6. The exploration of the impact on inhibitory performance of motor versus cognitive responses, presentation style, and response set showed that although these factors do not seem to particularly affect children with autism in comparison to controls, they do play a large role in determining the inhibitory performance of all participants. Finally, it was concluded that there is evidence for a differential impairment of prepotent response and resistance to distractor inhibition in children with autism, with children with autism being impaired in resistance to distractor inhibition while maintaining intact prepotent response inhibition.
|Date of Award||2010|
|Supervisor||Chris Jarrold (Supervisor)|