Activity in a brain region that regulates emotions fluctuates over the course of a woman's menstrual cycle, according to a new brain-imaging study.
Up to half of all women experience a variety of emotional symptoms, such as mood swings, irritability, and depression, during the days leading up to their periods. Combined with physical complaints, including bloating and cramping, these symptoms are collectively called premenstrual syndrome (PMS).
Although the emotional symptoms of PMS are well documented, says David Silbersweig of Cornell University, researchers know little about how the menstrual cycle affects women's brains.
To investigate, Silbersweig and his colleagues recruited 12 healthy women between the ages of 22 and 35. The researchers specifically selected women who reported having none of the emotional symptoms of PMS.