Researchers have identified the brain circuits that compel mice to seek out sweet treats.
Kay Tye of the Massachusetts Institute of Technology in Cambridge and her colleagues genetically engineered mice so that the neurons in a brain circuit involved in reward processing would fire when exposed to light. When the researchers activated these neurons, the animals sought sugar more frequently through a port in their cage, even when they received a mild electric shock to their feet in the process. Switching the neurons off stopped the sugar-seeking behaviour, but did not prevent the mouse from eating its normal food.
The researchers propose that targeting this pathway could be a possible therapy for compulsive overeating.