Neuromodulator

A neuromodulator is a substance other than a neurotransmitter, released by a neuron at a synapse and conveying information to adjacent or distant neurons, either enhancing or damping their activities.

A neuromodulator is a relatively new concept in the field and it can also be considered as a neurotransmitter that is not reabsorbed by the pre-synaptic neuron or broken down into a metabolite. Such neuromodulators end up spending a significant amount of time in the CSF (cerebrospinal fluid) and influencing (or modulating) the overall activity level of the brain. For this reasons, some neurotransmitters are also considered as neuromodulators. Examples of neuromodulators in this category: serotonin and acetylcholine. Substance P and Octopamine are also being shown as a neuromodulators.

Neuromodulator