A diffusion model analysis of task set inertia and task set reconfiguration in ADHD

Switching is one of three primary executive functions alongside inhibitory control and updating but remains relatively understudied in childhood attention-deficit/hyperactivity disorder (ADHD) compared to investigations into working memory and inhibitory control deficits. Where extant literature in adults suggests that switch costs are due to a combination of task set inertia and task set reconfiguration costs, it is not clear which of these is most relevant to explaining ADHD-related atypicalities in performance.

Children with (N = 34) and without ADHD (N = 28) aged 8-12 (average age = 9.45) completed a 192-trial computerized cued switching paradigm. Diffusion model decomposition of the data was performed to identify cognitive subprocesses responsible for the switch.

Consistent with the switching literature in adults, switch costs for children were due to a combination of both task set inertia (reduced drift rate) as well as slower task set reconfiguration (Ter) on switch versus repeat trials. Children with ADHD were less accurate than non-ADHD controls, but the ADHD × Switch interactions were not significant for any variable, indicating that the deficit was general and not switch-specific. Lower accuracy was in turn attributed to slower general drift rate among children with ADHD.

This study contributes to a growing literature finding that the performance deficits in children with ADHD across executive and non-executive function tasks are related to lower-level perceptual decision-making weaknesses that have downstream effects on higher-order processing.