Convergence of emotion and conflict processing in the brain: Evidence from an EEG study. [PREPRINT]

This study explored the neural mechanisms underlying the amplification of the conflict-adaptation effect (CAE) by self-related emotions, using a replication of a study by Landman and van Steenbergen (2020). Electroencephalogram (EEG) data were analyzed during two successive trials (Trial N-1 and Trial N) in a prime-probe task, wherein participants responded to the color of target words, which could be congruent or incongruent with the color of the preceding distractor words. Corrugator muscle activity was also measured as an index of emotional valence. Orthogonal to conflict, word emotion (unpleasant and neutral) and its social context (self- and sender-related) were manipulated. We hypothesized that the emotional facilitation of conflict adaptation by self-related emotional words in Trial N-1 is driven by an affective amplification of conflict-related brain signals. Our behavioral results revealed that emotional words increased CAE, but this affect was not moderated by social context. At the neural level, we replicated earlier results related to conflict and cognitive control; conflict induced early theta synchronization in fronto-central areas and late alpha desynchronization in centro-parietal areas during Trial N-1. Those oscillations showed CAE patterns mirroring the behavioral effect in Trial N. Incongruence increased corrugator activity, indicating that conflict induced unpleasant emotion. Emotion induced neural modulation overlapping with the conflict processing observed in the theta and alpha frequency ranges, suggesting additive but not synergistic effects. Our results reveal neural modulation by conflict and emotional words that that might provide input for downstream processes that integrate these signals to drive emotional modulation of behavioral adaptation.