A pupillometric investigation of state regulation in adults scoring high versus low on ADHD symptomatology.

According to the state regulation deficit (SRD) account, ADHD is associated with difficulties regulating tonic arousal levels, which may be due to inefficient effort allocation. We aimed to test the SRD account by using a target detection task with three different event rates (ER; 700 ms, 1800 ms, 6000 ms), in order to manipulate the tonic arousal state and its effects on performance and pupil indices in adults with high (n = 40) versus low (n = 36) ADHD symptom levels. In an additional condition, a fast ER (700 ms) was accompanied by auditory white noise (WN), to further increase tonic arousal level. The ER manipulation had a clear effect on RT and variability of RT. These effects were more pronounced for the high-ADHD group, especially for variability of RT with decreasing ER, suggestive of deficient upregulation of a tonic arousal state in that group, in line with their self-reported SRDs in daily life. Adding WN to the fast condition led to more errors, however similarly for both groups. Contrary to our predictions, the ER manipulation had no effect on tonic pupil size (as a measure of tonic arousal). Phasic pupil amplitude (as a measure of cognitive effort) linearly increased with decreasing ER, suggesting more effort allocation during slower ERs. WN decreased phasic pupil amplitude, but had no impact on tonic pupil size. Importantly, however, no ADHD-related differences were present for the pupil indices. In conclusion, adults with elevated levels of ADHD symptoms reported more SRDs in daily life and showed a performance pattern that suggests difficulties in upregulating but not downregulating the tonic arousal state. Surprisingly, these findings were not accompanied by group differences in pupillometric indices. This casts some doubts on the relationship between these measures of autonomic nervous system activity and state regulation, in particular in the context of ADHD symptomatology.

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. (PsycInfo Database Record (c) 2021 APA, all rights reserved).