Neuroscientists have identified the neurochemical signal likely missing in Parkinson's disease by discovering 2 distinctly different kinds of neurons that deliver dopamine to an important brain region responsible for both movement and learning/reward behavior.

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Neuroscientists have identified the neurochemical signal likely missing in Parkinson's disease by discovering 2 distinctly different kinds of neurons that deliver dopamine to an important brain region responsible for both movement and learning/reward behavior.