Endocrine links between food reward and caloric homeostasis.

Both intrinsic and extrinsic (endocrine) inputs to the central nervous system (CNS) modulate motivation for feeding. Endocrine inputs such as insulin and leptin can have very rapid effects, but also the potential for chronic actions to decrease rewarding attributes of food. Future studies should elucidate the neural and cellular mechanisms which underlie these endocrine actions in the CNS.