Decoding congruency effects: Insights from reach actions and electroencephalography (EEG)

Poster Session A - Saturday, April 13, 2024, 2:30 – 4:30 pm EDT, Sheraton Hall ABC

Moaz Shoura¹ (moaz.shoura@mail.utoronto.ca), Katie Smith², Adrian Nestor¹, Christopher Erb²; ¹University of Toronto, ²University of Auckland

Behavioral performance in congruency tasks has provided important insights into the mechanisms of cognitive control. The present work aims to shed light on the neural basis of these mechanisms by evaluating the neural dynamics underlying reach actions in an Eriksen flanker task. Specifically, we collected electroencephalography (EEG) data while healthy adult participants reached to specific locations depending on the direction of an arrow embedded within a field of congruent or incongruent distractors. Then, we employed EEG pattern analysis to decode specific stimulus and response properties: current stimulus congruency (i.e., whether the target was congruent or not with the distractors), the congruency of the preceding trial and response type (i.e., whether participants responded with the same or different action relative to the previous trial). Overall, all properties could be decoded above chance, though current congruency was more robustly decoded that the other two. Importantly, combinations of properties could also be decoded reliably (e.g., current congruency when preceded by a congruent or by an incongruent trial). Further, the temporal profile of decoding was investigated across stimulus-locked patterns, with current congruency spanning an extensive interval of above-chance decoding between roughly 200ms to 750ms and peaking around 300ms after stimulus onset. This analysis was complemented by decoding of initiation-locked EEG patterns, which yielded convergent results. In summary, the current work characterizes the neural dynamics of cognitive control and paves the way for elucidating its relationship with behavioral performance.

Topic Area: EXECUTIVE PROCESSES: Goal maintenance & switching