Inhibitory control for food throughout the menstrual cycle

The menstrual cycle exerts a modulatory effect on appetite among females, with a notable increase in appetite and food consumption observed during the pre-menstruation. This phenomenon may be attributed to an inhibitory mechanism related to food intake, although the underlying neural substrates remain elusive. This study aims to elucidate the variations in the inhibitory control for food and its associated neural correlates throughout the menstrual cycle.Eleven healthy females with regular menstruation participated in the present study. Participants were asked to visit the laboratory at four distinct phases of their menstrual cycle: during menstruation (MP) and immediately post-menstruation (FP), at ovulation (OP), and during the pre-menstruation (LP). The inhibitory control for food was assessed using a food-related stop signal task (food-SST). During the food-SST, electroencephalography recordings were obtained to evaluate neural activity. The sequence of assessments was randomized among participants. A two-factor linear mixed model analysis with repeated measures (LMMRM) was employed to compare the data across menstrual phases and food categories (neutral, low-calorie food [LC], high-calorie food [HC]) as within-subject variables.The LMMRM analysis revealed no significant variations in reaction time to Go-signals across different food categories or menstrual phases. However, the reaction time for the stop-signal (SSRT) in the LC and HC exhibited a tendency to deteriorate during the LP in comparison to other menstrual phases (Figure 1).The present results indicate a diminished inhibitory control over food during the LP, potentially contributing to the heightened appetite and increased food intake observed during this phase.