Effects of Repeated Administration of an Inhibitory Control Task in the Absence of an Intervention

Repeated task administration is crucial to accurately measure cognitive change, but may introduce factors that influence task performance, potentially biasing conclusions. The potential effects of repeated task administration are well-documented in various neuropsychological tests, particularly as practice effects, yet the trajectory of these effects in inhibitory control tasks under controlled and field-appropriate conditions remains unclear. The present investigation aimed to evaluate changes in behavioral performance through the repeated administration of an inhibitory control task (i.e., a Simon Task including no-go trials) in the absence of intervention. Healthy young adults (N = 139; 19.4 ± 1.2 years; 58% female) completed up to 21 testing sessions asymmetrically (intertest interval ~5 days), over a 90-day period. No significant differences were observed for response suppression (i.e., accuracy on compatible/no-go trials) or interference (i.e., accuracy on incompatible trials) across completions. A reduction in reaction time across both compatible and incompatible trials was found following initial task completion but appears to stabilize thereafter as marginal variation in reaction time was observed between the 2^nd and 16^th task completions. Such findings are inconsistent with practice effects, highlighting the stability of inhibitory control task performance despite repeated administration. We recommend that future studies which incorporate an inhibitory control task take the necessary precautions when interpreting small effects and to mitigate the potential effects of repeated task administration.