Behavioral expression of food-associated memory in fruit flies is constrained by satiety and promoted by hunger, suggesting an influence of motivational state. Here, we identify a neural mechanism that integrates the internal state of hunger and appetitive memory. We show that stimulation of neurons that express neuropeptide F (dNPF), an ortholog of mammalian NPY, mimics food deprivation and promotes memory performance in satiated flies. Robust appetitive memory performance requires the dNPF receptor in six dopaminergic neurons that innervate a distinct region of the mushroom bodies. Blocking these dopaminergic neurons releases memory performance in satiated flies, whereas stimulation suppresses memory performance in hungry flies. Therefore, dNPF and dopamine provide a motivational switch in the mushroom body that controls the output of appetitive memory.
Journal article
Cell
16/10/2009
139
416 - 427
Animals, Appetitive Behavior, Behavior, Animal, Conditioning, Classical, Dopamine, Drosophila Proteins, Drosophila melanogaster, Memory, Motivation, Mushroom Bodies, Neuropeptides, Receptors, Neuropeptide