What causes brain fog in perimenopause

Fluctuating estrogen disrupts neurotransmitter activity (especially acetylcholine and serotonin). Sleep disruption and mood changes compound cognitive symptoms.

1 min readReviewed May 2026

By Sarah Editor, MA Journalism, Certified Menopause Coach · Medically reviewed by Jane Smith, MD, MD, NAMS-certified · menopause nams

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Last medically reviewed: 5/15/2026 · Last updated: 5/15/2026 · Next review due: May 2027

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Fluctuating estrogen disrupts neurotransmitter activity (especially acetylcholine and serotonin). Sleep disruption and mood changes compound cognitive symptoms.

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