In which system is acetylcholine an important neurotransmitter?

Acetylcholine is a crucial neurotransmitter involved in both the central nervous system (CNS) and the peripheral nervous system (PNS). In the CNS, acetylcholine plays a key role in various functions including memory, attention, and arousal. It is involved in the modulation of plasticity, synaptic growth, and neurogenesis, contributing to learning and memory processes.

In the PNS, acetylcholine is primarily known for its role at the neuromuscular junction, where it facilitates muscle contraction by transmitting signals from motor neurons to muscle fibers. Additionally, it is involved in autonomic functions, influencing processes such as heart rate and digestion.

This dual functionality in both systems illustrates its versatility and importance in regulating numerous physiological and cognitive processes.