Cortical activation during menopausal hot flashes

ObjectiveTo determine regions of brain activation associated with menopausal hot flashes and sweating.DesignControlled laboratory study.SettingUniversity medical center.Patient(s)Symptomatic postmenopausal women and asymptomatic eumenorrheic women.Intervention(s)NoneMain Outcome Measure(s)Brain activation measured by functional magnetic resonance imaging.Result(s)Significant (P<.001) areas of activation during hot flashes in symptomatic women included the insula and anterior cingulate cortex. Sweating in the eumenorrheic women was associated (P<.001) with activity in the anterior cingulate and superior frontal gyrus.Conclusion(s)Activation of the insular cortex is associated with the “rush of heat” described during menopausal hot flashes. Thermoregulation in humans appears to be represented in a distributed cortico-subcortical network rather than in a single localized structure.