Response Inhibition and Immediate Arousal by Raymaekers et al. (2006) - Article

It has long been the goal of many researchers to investigate the number of impairments that underlie the symptoms which characterize Autism Spectrum Disorder (ASD). Through the use of the executive functioning criteria, studies on ASD have highlighted planning, cognitive flexibility, and working memory to be areas which are weak in individuals with the disorder. The area of response inhibition is what the authors chose to focus on. More specifically, the study aimed to use an immediate arousal task to examine inhibition of responses in children with high functioning autism (HFA), and to look for an association with impulsivity, hyperactivity, or inattention.

Procedure

Participants for the study consisted of 39 children with HFA and a control group of 29 average functioning children. Once written permission was obtained from the parents, questionnaires were sent to the children to ascertain their suitability and possible comorbid disorders. The task consisted of a computer based reaction test. Participants were instructed in condition A to press a response button as quickly as they could upon the appearance of a white cross onscreen. In condition B they were instructed to wait for an acoustic signal before reacting as fast as they could to a white cross onscreen. The speed of the presentation rate was varied. An A-B-B-A style of sequencing of conditions was used.

Results and discussion

The aim of the study was to examine whether or not there existed a response inhibition deficit in children with HFA. The presentation of an auditory signal and a visual stimulus produced an arousal effect which resulted in an increase in error rate and a decrease in reaction time. It was hypothesized that this effect would be strongest in children with HFA. Inhibition errors did increase with the addition of the auditory signal, however this was not unique to the HFA group. The results of this study suggest that children with HFA don’t have a deficit in the inhibition system. This result is in dispute of some studies.