Brain Circuitry May Trigger Overeating

Scientists have discovered that the BNST gaba neurons are an outcropping of the amygdala, the part of the brain associated with emotion. The BNST also forms a bridge between the amygdala and the lateral hypothalamus, the brain region that drives primal functions such as eating, sexual behavior and aggression. The researchers implanted fiber optic cables in the brains of mice, allowing them to shine light through the cables and onto BNST synapses. As soon as the light hit BNST synapses the mice began to eat voraciously even though they had already been well fed. Moreover, the mice showed a strong preference for high-fat foods. Science, Sept. 2013