State regulation in adults scoring high versus low on ADHD symptomatology : a pupillometry study

Objective: According to the state regulation deficit account, attention deficit/hyperactivity disorder (ADHD) is associated with difficulties in maintaining an optimal level of cognitive arousal. As the precise locus of this problem is yet unknown, the present study investigated this through behavioral and pupillometry indices. Method: Adults scoring high versus low on ADHD symptomatology carried out a target detection task at three event rate (ER) levels. Phasic pupil dilation was used as an index of cognitive effort, and tonic pupil size as an index of tonic arousal. Results: Performance and self-reports indicated state regulation difficulties in the high-ADHD group. Phasic pupil dilation was increased during slow ER, indicating additional effort allocation. Surprisingly, tonic pupil size was smallest in the fast ER, and group effects were absent for both pupil measures. Conclusion: The high-ADHD group showed state regulation difficulties despite similar levels of additional effort allocation as reflected by phasic pupil responses