Hunger is more powerful than thirst and fear
The sensation of hunger is more powerful than fear or thirst, a new study claims.
The National Institutes of Health conducted research into the topic using mice, putting the rodents in different scenarios requiring them to choose between different cravings. Scientists deprived them of food for 24 hours or triggered neurons to make the mice hungry, with the same done for thirst, and they were exposed to fox scents to scare them.
It was found that the mice which were both thirsty and hungry ended up eating more food rather than drinking water. Furthermore, the hungry mice in the space filled with fox scents would still venture ahead for food, despite the apparent threat, whereas the mice which had been fed stayed close to the corners and away from the scented area rather than going out to eat.
This also means the mice separated themselves socially in order to find food and those which were hungry were more likely to stay in an area with food than another different one with other mice.
The study, conducted by carried out by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), found AgRP neurons might act to boost hunger over other cravings. These neurons are located in the nerve centre of the brain, known as the hypothalamus, which controls hormone releases and the nervous system. It’s thought these findings can help experts understand eating disorders and how to stop food cravings to tackle issues like obesity.
“We interpret this as a unique ability of hunger-tuned neurons to anticipate the benefits of searching for food, and then alter behaviour accordingly,” lead author Dr Michael Krashes said.
He adds that the NIDDK now hopes to conduct more studies into how AgRP neurons affect other brain regions during motivated behaviours, explaining: “These interrelationships are highly complicated and further work will need to delve much more deeply into understanding how these interrelationships work on the neural level.
“Our continued existence, among that of other species, has motivated us to pursue an array of behaviours, all governed by our nervous system. Of course, we can't pursue all those motivations at once, so we have had to choose which ones were most important during different times of need.”