Objective: To determine regions of brain activation associated with menopausal hot flashes and sweating.
Design: Controlled laboratory study.
Setting: University medical center.
Patient(s): Symptomatic postmenopausal women and asymptomatic eumenorrheic women.
Intervention(s): None.
Main 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.