Physical Activity and Neural Correlates of Sad Facial Expressions in Premenstrual Syndrome

Exercise benefits our emotional function, particularly frontal lobe-mediated cognitive processes. Recent studies have indicated that affective neural circuits are modulated by premenstrual syndrome (PMS). Meanwhile, observational studies have reported that physical activity can promote PMS remission. Nonetheless, few studies have investigated the effect of physical activity on sad emotion recognition from a neurobiological perspective. Our objective was to explore the relationships between exercise and high order sad emotion cognitive processing in women with PMS. We conducted a sad facial emotion recognition task to examine the effects of aerobic exercise on activity in central frontal regions with electroencephalography in 31 participants. Participants were divided into a high (HPMS) or low severity PMS (LPMS) group according to self-reported PMS scores. We then analyzed cortical activity in response to sad cues, comparing such activity between the groups. Repeated ANOVA and pooled t statistics were used for statistical analysis. We observed a significant reduction in the N250 wave evoked by sad emotions after exercise compared with baseline at most channels in HPMS (P < 0.05), but not in LPMS. There was also a significant post-exercise prolongation of N250 latency at F3 and C3 in HPMS. There were no differences in N250 activation between the groups at baseline but significantly lower activation was noted in the lateral prefrontal cortex (PFC: F7 and F8) of HPMS compared with LPMS after exercise. Furthermore, higher PMS scores were significantly associated with greater PFC-N250 amplitude before exercise, but this was not observed after exercise. Acute exercise induced significant brain activity changes in response to sad cues in the HPMS group only. Furthermore, significantly lower activation of the lateral PFC was found after exercise in HPMS compared with LPMS. Given our results, we discuss the potential efficacy of exercise to modulate emotional context or sad emotion regulatory capabilities in women with PMS.