The Neurobiology of Hunger

Weight loss leads to an intense motivation to seek and consume food. We are examining the contribution of hypothalamic neurons to homeostatic hunger. Optogenetic activation of hypothalamic AGRP neurons rapidly induces hunger in mice. The motivational properties of AGRP neuron activity as well as in vivo calcium dynamics indicate that these neurons influence hunger responses through a negative valence teaching signal. These studies reveal a key role for AGRP neurons in learning about food. Our findings are consistent with a neuronal basis for negative emotional attributes of weight loss diets.