Enhanced neuroactivation during verbal memory processing in postmenopausal women receiving short-term hormone therapy

Abstract

To study the effects of hormone therapy on brain activation patterns during verbal memory in postmenopausal women. A randomized, double-blind placebo-controlled cross-over study was performed. A tertiary care university medical center. Ten healthy postmenopausal women (age range 56-60 years) were recruited from the local community. Women were randomized to the order they received combined hormone therapy, 5 microg of ethinyl E(2) and 1 mg of norethindrone acetate, and placebo. Volunteers received hormone therapy or placebo for 4 weeks, followed by a 1-month washout period, and then received the other treatment for 4 weeks. A functional magnetic resonance imaging (fMRI) was performed at the end of each 4-week treatment using a verbal memory task. Brain activation patterns were compared between hormone therapy and placebo. Hormone therapy was associated with increased activation in the left middle/superior frontal cortex (BA 6,9), medial frontal cortex and dorsal anterior cingulate (BA 24,32), posterior cingulate (BA 6), and left inferior parietal cortex (BA 40) during memory encoding. All regions were significant with correction for multiple comparisons. Hormone therapy increased neural activation in frontal and parietal areas in postmenopausal women during a verbal memory task.