Arousal and Anxiety in Children with Autism Spectrum Disorders

Background: Many children with Autism Spectrum Disorders (ASDs) are diagnosed and treated for anxiety disorders. However, deficits in communication and decreased understanding of emotions, in others and in one's self, make self-report of anxious symptoms difficult in this population. Some investigations have explored the psychophysiology of arousal in children with ASDs to better understand the manifestation of anxiety in this population. However, these investigations have not yielded conclusive findings and explore individual arousal mechanisms. We have developed a paradigm to explore multiple measures of arousal and data on anxiety in children with High Functioning Autism (HFA) undergoing a social stressor. Objectives: Short Term: To investigate preliminary, individual differences in physiologic response and self-reports of anxiety to a social stressor in a cohort of children with HFA and a group without HFA. Long Term: To relate these physiologic findings to parent and self-report of anxiety symptoms. Methods: We collected pilot data in 8-12 year old children with community diagnoses of HFA (n=19, 16 males) and those without HFA (n=12, 7 males) on measures of physiologic arousal at baseline, while undergoing a social stressor (The Trier Social Stress Test, TSST), and after a recovery period. The TSST consists of 3 tasks performed in front of 2 adult evaluators: 1) an oral story completion, 2) oral serial substractions, and 3) a tracing exercise done while looking through a mirror. The measures include electrodermal activity (EDA), salivary cortisol reactivity (CORT), and vagal tone (VT). Cortisol was measured at 3 points during the baseline, once following the TSST, and once at recovery. VT and EDA were averaged over multiple, coinciding 4 minute intervals during the 3 epochs. Each participant also rated his/her own anxiety during each activity on a 1-10 scale. Results: Both groups demonstrated an expected decrease in VT and increase in EDA during components of the TSST when compared to the baseline and recovery period. Preliminary analyses demonstrate children with HFA were less likely to have an expected cortisol level increase following the TSST while the non-HFA children were more likely to have an increase, although findings did not achieve statistical significance . For both groups, self-reported anxiety was higher during the TSST than during baseline and recovery. Within and between group differences in physiologic measurements and their relationship to self-reported anxiety will be described. Conclusions: We have developed an assay that incorporates psychophysiology and self-reported anxiety to better understand manifestations of arousal and anxiety in children with HFA and potentially other ASDs. While these results are preliminary and descriptive, with continuation of this study we will be powered to detect significant differences between the two groups. We will also incorporate parent reports of anxiety to analyze correlations between psychophysiologic measures of arousal, self-reports, and parent reports of anxiety.