Understanding Thirst

By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) - We are creatures dependent on water. There is no doubt that our bodies tell us when we need water by making us thirsty and desirous of more. But how does thirst work?

A report in the journal Nature based on a study in mice has led to an interesting theory. Water consumption helps to regulate the salt and water balance in the body and it is the hypothalamus, a part of the brain that has been implicated.

In this part of the brain, distinct populations of neurons or nerve cells are found to regulate water consumption.

There are different triggers. Fascinating reasearch has demonstrated that light activation of one set of neurons can evoke intense drinking behavior, even in water-satiated animals, whereas light-induced activation of a different set of neurons suppresses drinking.

It is truly a complex relationship in the brain.