Anhedonia and depression arise when POMC neurons in the arcuate nucleus of the hypothalamus become hyperactive as a result of chronic stress. Reducing the activity also reduces feelings of depression and loss of pleasure.
Chronic stress causes autophagy in adult hippocampal neural stem cells. This results in a decline of hippocampal neurogenesis. Cognitive deficits and mood disorders that arise as a result of chronic stress are a result of autophagic death of hippocampal neural stem cells.