Neurochemistry is the area of science that focuses on the chemistry of the nervous system. The chemicals of the nervous system are called neurotransmitters. These chemicals are used to transmit signals between cells and carry information to and from the brain. As early as 1904, scientists suspected that chemicals might be involved in the transmission of nerve impulses. However, acetylcholine, the first neurotransmitter to be identified, was not isolated until the early 1920s.

To understand neurochemistry, it may be helpful to review the structure and function of the nervous system and its component parts. The nervous system contains cells called neurons. Neurons come in many different shapes and sizes, but they all have the same basic parts: dendrites and cell body, axons, and axon terminals. Dendrites are extensions of the cell body. The dendrites and cell body are where signals are received. The cell body also contains the organelles...