Acetylcholine is a neurotransmitter used at the neuromuscular junction—that means, it is the chemical that motor neurons of the nervous system release in order to activate muscles.
In the brain, acetylcholine functions as a neurotransmitter and as a neuromodulator. The brain contains a number of cholinergic areas, each with distinct functions. They play an important role in arousal, attention, memory, and motivation.
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