West LA Times

A new study conducted by UCLA researchers has uncovered a fascinating connection between food-seeking behavior and specific brain cells in mice. The research, published in the journal Nature Communications, reveals that these cells, located in a part of the brainstem associated with panic, play a crucial role in driving animals to seek out food, even when they are not hungry.

Corresponding author Avishek Adhikari, a UCLA associate professor of psychology, explained, "Activation of the entire PAG region causes a dramatic panic response in both mice and humans. But when we selectively stimulated only this specific cluster of PAG neurons called vgat PAG cells, they did not alter fear, and instead caused foraging and feeding."

The study found that when these specific cells were stimulated in mice, the animals exhibited a strong desire for fatty and pleasurable foods, even enduring foot shocks to obtain them. This behavior indicates that the circuit is not driven by hunger but rather by a craving for highly rewarding, high-caloric foods.

Fernando Reis, a UCLA postdoctoral researcher involved in the experiments, noted, "Mice show compulsive eating in the presence of aversive direct consequences when this circuit is active, and don’t search for food even if they’re hungry when it’s not active. This circuit can circumvent the normal hunger pressures of how, what and when to eat."

The implications of this research extend beyond mice, as humans also possess similar vgat PAG cells in their brainstems. If the findings are confirmed in humans, they could offer new insights into understanding and potentially treating eating disorders. Adhikari pointed out, "People possess the same kinds of cells, and if confirmed in humans, the finding could offer new ways of understanding eating disorders."

The study was supported by several organizations, including the National Institute of Mental Health, the Brain & Behavior Research Foundation, and the National Science Foundation.