Glossary

neuromodulator

A neuromodulator is a chemical substance released from a neuron in the central nervous system (the brain or spinal cord), or in the periphery, that transmits information to other neurons, altering their activities. A neuromodulator affects not just a single cell, but groups of neurons or effector cells that have the appropriate receptors. Unlike a neurotransmitter, it may be released at sites other than synaptic sites, it often acts through second messengers, and it can produce long-lasting effects. The release may be local, so that only nearby neurons or effectors are influenced, or it may be more widespread.