Two groups of neurons, each governed by different genes, drive a mouse’s thoughts on thirst, researchers report in the Jan. 26 Nature. Both sets of neurons are found in the hypothalamus, the region of the brain that also regulates hunger, body temperature and sleep.
Optogenetic experiments in mice indicate that one set of neurons triggers the body’s need to take drink, while another set tells the body it’s hydrated and doesn’t need a drink. The findings held even in well hydrated and thirsty mice. The neurons only control thirst, so the hypothalamus could be divided into cells that control specific cravings, the researchers suggest.