A brain circuit that links hunger signals with the jaw movements of eating

A simple neural circuit connects a satiety-inducing hormone with feeding movements, including chewing and biting. Hunger signals activate neurons in the arcuate nucleus of the hypothalamus. These project to neurons in the ventromedial hypothalamus, which, in turn, regulate further neurons in the perimesencephalic trigeminal area that control muscles required for feeding. In mice, silencing a set of neurons in the brain’s hypothalamus leads to chewing behaviours, even when food is unavailable.