Non-randomised trial, 2004
Does the menstrual cycle affect brain activity related to memory and attention?
Yes. Brain electrical activity related to attention (the P300 response) was significantly stronger during menstruation than during ovulation. Memory effects were similar at both cycle phases.
What they did
Researchers measured brain electrical activity (event-related potentials) in 12 women while they performed memory tasks at two cycle phases: menstruation and ovulation. Women saw words on a screen, some of which repeated after about 6 trials, in two types of memory tasks.
What they found
The P300 amplitude, which reflects attention and context updating, was significantly greater during menses than during the ovulatory phase. The repetition effect (brain response to seeing words repeat) was significant at both cycle phases but did not differ between them.
What it means for you
This suggests attention and context-updating processes in the brain change across the menstrual cycle, with stronger responses during menstruation. However, this is a very small study with no control group for comparison, so clinical significance is unclear. The women studied did not have mood disorders.
12
Women studied
6
Mean trials between word repetitions
About the study
- Original title
- The effect of the menstrual cycle on electrophysiological and behavioral measures of memory and mood
- Authors
- O'Reilly MA, Cunningham CJ, Lawlor BA et al.
- Journal
- Psychophysiology
- Year
- 2004
- Study design
- Non-randomised trial
- What was tested
- No intervention; brain activity was measured during memory tasks.
- Read the paper
- doi.org/10.1111/j.1469-8986.2004.00194.x
Topics
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