Study, 1993
Does the ability to think clearly change with the menstrual cycle?
Yes. When women were tested in their premenstrual phase versus their preovulatory phase, they showed more difficulty suppressing irrelevant information and following instructions. The difficulty was more pronounced in women who reported worse premenstrual symptoms.
What they did
20 women with an average age of 30.4 years completed a thinking task twice: once during preovulatory phase and once during premenstrual phase. The Mental Dice Task asked them to generate random numbers from 1 to 6. They rated their premenstrual symptom severity.
What they found
All the women showed fewer repetitions and more counting patterns in their random number sequences compared to real dice rolls, at both testing times. During the premenstrual test, this counting bias was stronger. Women who reported worse premenstrual symptoms showed a bigger increase in this bias. The researchers thought this indicated reduced ability to ignore task-unrelated thoughts and weaker frontal lobe function.
What it means for you
Thinking and decision-making ability may change through the menstrual cycle, particularly the ability to suppress distraction and follow instructions. This happened with self-reported cognitive symptoms, suggesting thinking changes are real. The study was small and tested only one task, so findings may not apply to other kinds of thinking.
20
women
30.4
average age (years)
2
test sessions
About the study
- Original title
- Random-number generation and the menstrual cycle: preliminary evidence for a premenstrual alteration of frontal lobe functioning
- Authors
- Brugger P, Milicevic A, Regard M et al.
- Journal
- Perceptual and motor skills
- Year
- 1993
- Study design
- Study
- Participants
- 20
- What was tested
- Testing on Mental Dice Task during preovulatory and premenstrual phases
- Read the paper
- doi.org/10.2466/pms.1993.77.3.915
Topics
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