Localized brain metabolite changes during visual sexual stimulation in postmenopausal women

Abstract

Functional magnetic resonance spectroscopy was used to compare brain metabolite changes between nonpostmenopausal and postmenopausal women exposed to visual sexual stimulation with erotic video clips. Twenty nonpostmenopausal women and 20 postmenopausal women were enrolled in this study. Menopause was defined as continuous amenorrhea for more than 12 months and a follicle-stimulating hormone level higher than 40 mIU/mL. Brain metabolite concentrations were measured from a localized voxel on the anterior cingulate gyrus, one of the most important areas associated with sexual arousal. Subjective sexual arousal and attention to visual stimulation were assessed using a 5-point scale. Functional magnetic resonance spectroscopy data were acquired from nonpostmenopausal and postmenopausal women during rest and activation conditions. Compared with nonpostmenopausal women, postmenopausal women showed significantly lower levels of both βγ-glutamate/glutamine and lipid during the "rest" period but had lower levels of βγ-glutamate/glutamine only during the "activation" period (P < 0.05). This study finds differential brain metabolite changes during visual sexual arousal in nonpostmenopausal and postmenopausal women. These findings would be helpful in understanding the neural mechanism of visual sexual arousal in connection with brain metabolite changes after menopause.