Neuroimaging of aging and estrogen effects on central nervous system physiology

Objective: To review the literature on neuroimaging studies focusing on gender differences in the aging process and on the effects of postmenopausal estrogen use on the brain.Design: Pertinent studies were identified through a computer MEDLINE search. References of selected articles were hand-searched for additional citations.Conclusion(s): The current literature suggests that estrogen replacement may decrease brain white matter lesions, increase cerebral blood flow, alter regional brain activation patterns during cognitive processing, and have modulatory effects on various neurotransmitter systems. Overall, this points to a functional plasticity in higher order brain processing that can be altered by gonadal steroids.