New Scientist is reporting that the ‘moodiness’ experienced by some women during the premenstrual phase of the menstrual cycle may be linked to the function of the orbitofrontal cortex.
The oribitofrontal cortex (OFC), the part of the brain that lies just above the eyes, is known to be involved in emotional regulation.
The research, led by (the wonderfully named) Xenia Protopopescu from Cornell University, brain-scanned 12 women who did not experience mood changes during their menstrual cycle.
They found that an area in the OFC increased in activity when participants reacted to emotionally-laden words during an experimental task when in their premenstrual phase.
Crucially, there was less recorded activity for the same task when it was completed during the post-menstrual phase, suggesting emotional regulation was most needed during the earlier, premenstrual period, to maintain a steady mood.
The researchers have suggested that women who experience fluxations in mood during their cycle may not have such effective emotional regulation, although the exact mechanism of how the hormonal changes affect the function of the brain is still unclear.
The complexity of the issue is highlighted by the finding that other, more dispersed areas of the OFC, showed the opposite pattern of activity during the same experiment.