---
title: Does brain activity change across the menstrual cycle? | Niyora
description: 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
url: https://niyora.com/research/papers/female-menstrual-phases-modulate-human-prefrontal-asymmetry-a-2009/
---

- [Niyora](https://niyora.com/)
- [Research](https://niyora.com/research/)
- [Library](https://niyora.com/research/library/)
- Does brain activity change across the menstrual cycle?

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.

 Early or limited evidence

14 healthy women

## 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](https://doi.org/10.1016/j.yhbeh.2008.10.008)

## Topics

[Menstrual cycle and mood](https://niyora.com/research/topics/condition-cycle-mood/)[Anxiety and tension](https://niyora.com/research/topics/symptom-anxiety/)[Adolescents and young people](https://niyora.com/research/topics/life-area-adolescents/)

Research tells you what helps on average. Niyora helps on the day it hits.

Calm down, see it another way, and decide what to say, with a PMS and PMDD app built by a doctor.

## Related studies

Randomised trial, 2026

Does aerobic or resistance exercise reduce anxiety in women with PMS?

Cohort study, 2025

How common is PMS in Chinese teenage girls, and what factors are linked to it?

Survey study, 2026

Is worry about climate change linked to worse PMS symptoms?

Survey study, 2023

Do stomach and gut problems change during the menstrual cycle?

Survey study, 2023

How common are PMS, PMDD, anxiety, and depression in rural adolescent girls?

Survey study, 2021

What factors affect premenstrual syndrome in teenage girls?

Ask AI about this page

Copy prompt

ChatGPT

↗

Claude

↗

Perplexity

↗

Google AI Mode

↗

Grok

↗