You know the feeling: the dryness in the mouth, the stickiness in the throat and the creeping salivation — thirst.
But what causes feelings of thirst in the brain? In a new study, scientists used laser light to activate groups of neurons in the brains of mice. By targeting specific neuron groups, the scientists could make the animals drink even if they weren't thirsty, and stop drinking even if they were thirsty.
Understanding how the brain causes feelings of thirst could help scientists learn what goes awry in disorders that make people drink too much or too little fluid, researchers say.
"Thirst has attracted a lot of interest because it is such a basic function for all organisms," said Yuki Oka, a neuroscientist currently at the California Institute of Technology and co-author of the study published today (Jan. 26) in the journal Nature.