Dopamine is a chemical messenger between nerve cells that is associated with reward and addiction, among other things.

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It results from a loss of cells in the brain that produce a chemical messenger called dopamine, which coordinates movement.

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It seems to stimulate overeating by speeding up production of a chemical messenger in the brain called GABA, or gamma-amino butyric acid.

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One of the key culprits in the cascade is a chemical messenger called glutamate, which normally plays a crucial role in learning and memory by stimulating nerve cells to fire.

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