The menstrual cycle affects recognition of emotional expressions: an event-related potential study

BACKGROUND Several studies have investigated the relationship between behavioral changes and the menstrual cycle in female subjects at a reproductive age. The present study investigated the relationship between the menstrual cycle and emotional face recognition by measuring the N170 component of ERPs. METHODS We measured N170 of twelve women in both follicular phase and late luteal phase who were presented with human facial expressions as stimuli (happy and angry). RESULTS In the follicular phase, participants showed a significantly larger response to happy male facial expressions. In the late luteal phase, participants had longer reaction times to all emotional stimuli, and a significantly reduced response to happy faces, especially happy male facial expressions (P<0.001). CONCLUSIONS Our findings suggest that the menstrual cycle modulates early visual cognitive processing, and highlight the importance of considering the menstrual cycle phase in studies that investigate emotion and cognition.