The neurobiological substrates of depression in Parkinson's disease: a hypothesis.
Evidence from a variety of sources indicates that the mesolimbic-mesocortical dopamine projections may play an important role in some types of reward or reinforcement processes in animals. There is circumstantial evidence that this is also true in humans. Since a reduced ability to experience pleasure or reward (i.e. anhedonia) is a cardinal feature of clinical depression, and since the mesolimbic and mesocortical dopamine projections have been shown to degenerate in Parkinson's disease, it is suggested that damage to these reward-related systems may contribute directly to the high incidence of depression that has been reported in this disease.
D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology; D003213:Conditioning, Psychological; D003863:Depression / Q000150:complications / Q000503:physiopathology*; D004298:Dopamine / Q000502:physiology; D005625:Frontal Lobe / Q000502:physiology; D006801:Humans; D008032:Limbic System / Q000502:physiology; D009410:Nerve Degeneration; D009420:Nervous System / Q000503:physiopathology*; D010300:Parkinson Disease / Q000150:complications*; D051381:Rats; D012054:Reinforcement, Psychology; D012201:Reward; D009435:Synaptic Transmission
D004298:Dopamine