An investigation of autonomic arousal and attentional mechanisms in children with ADHD and Autism

Abstract

The present doctoral project was aimed at investigating the impact of Attention Deficit Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) on measures of physiological arousal, alerting/vigilance, attention orienting and executive functions. 106 children between 7 and 15 years of age (31 typically developing; 24 ADHD-only; 18 ASD-only; 33 ADHD&ASD) performed a battery of eye-tracking and EEG experimental paradigms, while parent-reported measures were used to evaluate the severity of symptoms of ASD, ADHD and other psychiatric conditions. Children with clinical diagnoses of ADHD and ASD showed condition-specific signs of dysregulated physiological arousal and vigilance, with ADHD more likely to be associated with difficulties in up-regulating and maintaining an optimal level of vigilance to the environment, and ASD more associated with over-reactivity to sensory information and difficulties in down-regulating autonomic arousal in line with contextual demands. We also demonstrated that executive function and cognitive control mechanisms are likely to be less effective in children with comorbid ADHD+ASD, with negative effects on performance accuracy. In the discussion of this dissertation, some suggestions for clinical practice and future research studies, besides a description of the implications of the findings on the everyday life of people with ADHD and/or ASD, are provided