On Jul. 10, 2024, Scripps Research scientists announced they have identified a group of neurons in a small and understudied region of the brain—the parasubthalamic nucleus (PSTN)—that controls when an animal decides to take a first bite of food.

In the study, published in Molecular Psychiatry on July 4, 2024, the team of scientists set out to selectively manipulate a group of PSTN cells that dial up their activity during periods of binge-eating. Other scientists have observed that many PSTN cells become active following a large meal, but the team wondered how these cells might influence appetite.

The research team found that the ensemble of cells sensitive to binge-eating were capable of drastically changing the behavior of mice. Hungry mice normally start chowing down on food quickly once it becomes available to them. But when researchers turned on this ensemble of PSTN cells, mice were much slower to begin eating and, surprisingly, much faster to drink water.

By manipulating even smaller sets of cells within the PSTN, the team pieced apart exactly which groups of cells were responsible for the delayed eating and accelerated drinking. They also discovered that yet another group of PSTN cells drives a different effect, urging the mice to eat more sweet foods. 

“Altogether, these results reveal that PSTN neurons exert a complex combination of functions,” says senior author Candice Contet, PhD, associate professor in the Department of Molecular Medicine at Scripps Research. “Several studies had previously shown that PSTN activity can limit the amount of food eaten, but the fact that certain PSTN neurons control the onset of feeding or drinking, or even promote the consumption of food ‘treats,’ is entirely novel.”