The brain is our control centre. Every part of the body follows the signals and instructions sent out by the brain. It’s the very root that determines why, how and where body fat is stored. It drives our motivation to exercise (or not), and regulates hormone production, metabolism, hunger and food choices. But what part of the brain can actually switch off hunger cues?
A team of researchers at The Rockefeller University in New York City, have identified just this, proving there is a group of nerve cells (or neurons), which when activated, reduces food intake.
The mechanism centres on dopamine 2 receptor (hD2R) neurons in the hippocampus, a brain structure that has a role in memory formation and the regulation of emotions.
“These cells keep an animal from overeating”, said the first study’s author and postdoctoral researcher in the Laboratory of Molecular Genetics, Estefania P. Azevedo.
“They appear to make eating less rewarding and, in that sense, are tuning the animal’s relationship to food.”
To conduct the study, Azevedo and her team of researchers examined the brains of mice, and found hD2R neurons influenced their feeding behaviour. When the researchers stimulated the cells, the mice at less food, and when they silenced, the animals ate more food.
So, how could this help curb overeating? The team then went on to investigate how the hD2R neurons influence processes that help animals remember food locations.
The researchers found that by stimulating the hD2R neurons, the mice were less inclined to return to locations where they had found food. This suggests the cells weaken memories about meals and their locations, and therefore stop an animal from going back for more food.
The results, published in the journal Neuron, concluded that the brain “fine-tunes” appetite by balancing memory related mechanisms for promoting eating, and therefore hacking this function can stop an individual from overeating.
“So it is possible that, with training, people may be able to learn to change their relationship to food,” explained Azevedo.