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.