Neuromodulation refers to the regulation of neural and synaptic function by regulatory extrinsic or intrinsic substances.

Computational modeling of neural substrates provides an excellent theoretical framework for the understanding of the computational roles of neuromodulation. Neuromodulation can be defined as biophysical processes that serve to modify – or modulate – the computation performed by a neuron or network as a function of task demands and behavioral state of the animal. These modulatory effects often involve substances such as acetylcholine (ACh), norepinephrine (NE), histamine, serotonin (5-HT), dopamine (DA), and a variety of neuropeptides. Modulatory effects are difficult to define, because they often originate from different structures and have different spatial distributions and time courses of action. Because of the wider use of modeling techniques and growing interest in systems neuroscience, the computational role of neuromodulation...