Imaging and menopausal hot flashes

Farrell recently published an interesting review paper on imaging human brain responses during heating and cooling. Here, he discussed our work on imaging such responses during menopausal hot flashes (HFs). Hot flashes are triggered by small elevations in core body temperature acting within a greatly reduced interthreshold zone in symptomatic menopausal women. This reduction is due to estrogen withdrawal and increased sympathetic activation among other factors. There is an a2-adrenergic component in this mechanism, as demonstrated by the fact that HFs can be provoked by yohimbine, an a2-adrenergic antagonist and inhibited by clondine, an a2-adrenergic agonist. 5