Survey study, 2009
Does brain activity change across the menstrual cycle?
Yes, brain activity in the prefrontal cortex shifts between different phases, with different sides of the brain being more active at different times. This is based on a small study.
What they did
Measured brain activity in 14 healthy women at different menstrual phases using magnetoencephalography while they looked at fearful faces. They measured brain responses in two time windows.
What they found
Brain activity showed different patterns across menstrual phases. The right side of the brain was more active during the periovulatory phase, while the left side became more active during the menstrual phase. In the menstrual phase, anxiety scores were associated with left prefrontal cortex activation.
What it means for you
The brain's emotional processing may change across the menstrual cycle. This is a very small study measuring brain waves in a laboratory, not everyday mood or behaviour.
14
women studied
200-300
milliseconds, first time window
300-450
milliseconds, second time window
About the study
- Original title
- Female menstrual phases modulate human prefrontal asymmetry: a magnetoencephalographic study
- Authors
- Hwang RJ, Wu CH, Chen LF et al.
- Journal
- Hormones and behavior
- Year
- 2009
- Study design
- Survey study
- Read the paper
- doi.org/10.1016/j.yhbeh.2008.10.008
Topics
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