Relations between voluntary emotion regulation, automatic emotion regulation, and frontal EEG asymmetry

Deficits in emotion regulation are characteristic of many psychiatric disorders such as Major Depressive Disorder. Recent studies have shown that humans can successfully enhance, maintain, and suppress negative emotion in the laboratory. Furthermore, relative left-sided baseline frontal EEG alpha asymmetry has been shown to be associated with one form of automatic emotion regulation: fast recovery from an emotional challenge. In the current study, we sought to extend these findings in one multi-day, within-subjects study. Participants who had previously visited the laboratory for two sessions of baseline EEG recordings returned for an additional baseline EEG recording session (average time between recording sessions = 56 months). Eyeblink startle magnitude and corrugator EMG activity were then recorded while participants passively viewed unpleasant and neutral pictures. On the second day, eyeblink startle magnitude and corrugator EMG activity were recorded while participants were instructed to enhance, maintain, or suppress their emotional responses to unpleasant pictures. We hypothesized that relative left-sided frontal asymmetry would be associated with fast recovery following picture offset on Day One, and with ability to voluntarily suppress emotion on Day Two. Relative left-sided lateral frontal EEG asymmetry at the current recording session was inversely correlated with corrugator activity immediately following picture offset. Relative right-sided frontal pole EEG asymmetry at the current recording session was associated with ability to enhance negative emotion. These findings are discussed in terms of helping to clarify popular conceptualizations of emotion regulation in the literature, and in terms of helping to understand the abnormalities in regulatory processes that may underlie various forms of psychopathology.