Resting EEG signatures of agentic extraversion: New results and meta-analytic integration

Both frontal asymmetry in the alpha band (8–13 Hz) and posterior versus frontal theta activity (4–8 Hz) have been suggested as resting encephalogram correlates of Trait BAS/Agentic Extraversion (BAS/AE). Here we present data from four independent studies that assessed these associations using various questionnaire measures of BAS/AE. In each study the expected correlation was significant for posterior versus frontal theta activity and further analyses showed that this effect extends into the delta frequency band – a brain rhythm recently implicated in reward processing and salience detection. In contrast, no significant correlations were observed between BAS/AE and frontal alpha asymmetry and a meta-analysis of all available data revealed that this association is considerably weaker and more inconsistent than generally assumed.