Midfrontal Theta Activity Is Sensitive to Approach-Avoidance Conflict

Abstract

Midfrontal theta (FMh) in the human EEG is commonly viewed as a generic and homogeneous mechanism of cognitive control in general and conflict processing in particular. However, the role of FMh in approach-avoidance conflicts and its cross-task relationship to simpler stimulus-response conflicts remain to be examined more closely. Therefore, we recorded EEG data while 59 healthy participants (49 female, 10 male) completed both an approach-avoidance task and a flanker task. Participants showed significant increases in FMh power in response to conflicts in both tasks. To our knowledge, this is the first study to show a direct relationship between FMh and approach-avoidance conflicts. Crucially, FMh activity was task dependent and showed no cross-task correlation. To assess the possibility of multiple FMh sources, we applied source separation [generalized eigendecomposition (GED)] to distinguish independent FMh generators. The activity of the components showed a similar pattern and was again task specific. However, our results did not yield a clear differentiation between task-specific FMh sources for each of the participants. Overall, our results show FMh increases in approach-avoidance conflicts, as has been established only for more simple response conflict paradigms so far. The independence of task-specific FMh increases suggests differential sensitivity of FMh to different forms of behavioral conflict. Copyright © 2022 the authors.