In mice, social stress selectively enhances excitatory input from the lateral hypothalamus to ventral tegmental area dopamine neurons projecting to the medial prefrontal cortex, but not to the medial nucleus accumbens, resulting in increased dopamine release in the medial prefrontal cortex during stress and driving increased intake of palatable fat.

When an animal experiences social stress, its body releases a stress hormone that acts on a brain region controlling reward signals. This hormone strengthens the connection between a specific brain area that responds to stress and dopamine neurons that send signals to the part of the brain responsible for decision-making. This stronger connection causes more dopamine to be released in the decision-making area, which makes the animal seek out and eat more fatty food. The same stress does not strengthen connections to the brain's main reward center, so the effect is specific to decision-making circuits.