The menstrual cycle and brain function: Myth-bashing

The menstrual cycle involves complex hormonal fluctuations that greatly influence the woman's physiological processes. Historically, menstruation has been stigmatized, leading to misconceptions about its impact on cognitive abilities.

While it has been widely debated how (not whether) these changes affect women’s thinking and performance - neuroscience has shown that the brain does change in different phases of the cycle.

But do these structural changes affect our (women's) brains the way we have been told for ages? Well, it turns out, that it is basically just myths.

The brain structure changes during the cycle
Neuroimaging research demonstrates that the brain undergoes subtle yet significant changes throughout the menstrual cycle.

While the total volume of gray matter (brain cells) remains stable, some regions show fluctuations that follow the cycle of the sex hormones.

For example, the hippocampus, a key area for memory formation and memory keeping, increases in gray matter volume from the premenstrual to later phases. Enhanced connectivity, at some points in the cycle, between the hippocampus and surrounding brain structures suggests improved memory-related functions.

The amygdala, which processes emotions, exhibits changes that correlate with mood variations during the cycle.

Similarly, fluctuations that occur in the caudate nucleus, hypothalamus, and thalamus are linked to pain perception during menstruation.

These findings underscore the dynamic nature of the female brain in response to hormonal changes.

Hormones and brain activity
Functional magnetic resonance imaging, or fMRI, is a brain scan that shows which parts of the brain are active in a given situation. It works by detecting changes in blood flow.

When a brain area is more active, it gets more oxygen-rich blood. Using fMRI, scientists can see how the brain works in real-time,

FMRI studies indicate that the natural hormonal shifts during the female cycle, influence brain activity across different regions. Estrogen and progesterone, the primary hormones regulating the menstrual cycle, seem to play a crucial role in modulating brain function too.

During the follicular phase, when estrogen levels rise, brain areas involved in reward processing show increased activity. This is associated with greater responsiveness to short-term rewards, as seen in decision-making tasks.

Additionally, the orbitofrontal cortex, a region responsible for emotional regulation, exhibits changes in activity levels, affecting responses to emotional stimuli.

Evidence for cognitive fluctuations?
Menstrual-related cognitive impairment has been largely anecdotal and not supported by proper scientific evidence. 

Some studies initially indicated that women might excel in verbal and memory tasks during the luteal phase while performing better in spatial tasks during menstruation.  But when controlled studies of higher quality were done later on these findings could not be replicated.

More recent analyses found little to no significant differences in attention, memory, and problem-solving abilities throughout the cycle. 

Here is a list of all the cognitive functions that have been shown to NOT change during the female cycle - aka - that are NOT affected by sex hormones

Attention stays the same
Many people wonder if the menstrual cycle affects focus and concentration. Studies looking at different phases of the cycle found no evidence that women’s attention changes. Whether they were using birth control pills or not, their ability to focus remained stable with no major changes in attention.

Creativity stays the same
Does creativity shift throughout the menstrual cycle? Research suggests it does not. No significant changes in creative thinking were found when comparing different cycle phases. Even when researchers looked at hormone-confirmed phases, creativity levels remained stable. More research is needed in this area, as only a few studies have explored the topic.

Decision-making and problem-solving stay unchanged
Executive function, which helps people make decisions, plan, and control impulses, also appears unaffected by the menstrual cycle. Studies show no meaningful differences in these abilities across different phases. Whether looking at accuracy or speed, results remained consistent. Among women using birth control pills, no significant changes were found either.

Intelligence does not fluctuate
Research has also looked at general intelligence and whether it varies with hormonal changes. Just like with attention and creativity, no significant differences were found in intelligence levels across the menstrual cycle.

Motor skills stay the same
Physical coordination and motor skills, such as reaction time and precision, are not influenced by the menstrual cycle. Studies found no differences in speed or accuracy, whether examining naturally cycling women or those using birth control.

Spatial skills and verbal abilities show minor differences
Spatial abilities, such as navigating and mentally rotating objects, showed some differences across cycle phases. Some studies found that women performed slightly better in spatial tasks during ovulation compared to other phases. However, these differences were not always confirmed when hormone levels were measured directly.

Similarly, verbal skills showed minor variations, with some studies suggesting improved performance during ovulation.

No evidence of mental fatigue
Some theories suggest that women might experience changes in speed and accuracy of thinking due to hormonal shifts. However, research does not support this. D

Despite physical symptoms such as fatigue during menstruation, cognitive abilities remain stable. This suggests that hormonal fluctuations do not significantly impact how quickly or accurately women process information.

Why do the results matter?
These findings challenge the common belief that the menstrual cycle influences cognitive performance.

While hormone levels do fluctuate, they do not seem to have a noticeable effect on brain function. Women perform just as well in thinking tasks, problem-solving, and decision-making throughout their cycle.

This research is important because it helps dispel myths that suggest hormonal changes make women less capable at certain times of the month.

Scientific evidence does not support the idea that women’s cognitive abilities are affected by their cycle, reinforcing the idea that they can confidently take on any challenge at any time!

About the scientific paper:

First author: Daisung Jang, Australia
Published: PLoS One, March 2025
Link to paper: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0318576