Cognitive Control Beyond Single-Item Tasks: Insights from Pupillometry, Gaze, and Behavioral Measures

Abstract

Cognitive control has been typically examined using single-item tasks. This has implications for the generalizability of theories of control implementation. Previous studies have revealed that different control demands are posed by tasks depending on whether they present stimuli individually (i.e., single-item) or simultaneously in array format (i.e., multi-item). In the present study we tracked within-task performance in single-item and multi-item Stroop tasks using simultaneous pupillometry, gaze, and behavioral response measures, aiming to explore the implications of format differences for cognitive control. The results indicated within-task performance decline in the multi-item version of the Stroop task, accompanied by pupil constriction and dwell time increase, in both the incongruent and the neutral condition. In contrast, no performance decline or dwell time increase was observed in the course of the single-item version of the task. These findings point to capacity constraints beyond the explanatory range of current theories of cognitive control, with implications for cognitive control research, and highlight the need for better understanding the cognitive demands of multi-item tasks.