Neuromodulation of Hippocampal Cells and Circuits

Neuromodulation is the process by which the properties of neurons and synapses are altered by neuroactive substances termed neuromodulators. The distinction between neuromodulation and classical neurotransmission can be fuzzy but in general neuromodulation is more diffuse, less targeted, and acts over a longer time course than classical fast neurotransmission. Often the same neurochemical may have rapid neurotransmitter-like effects followed by more sustained modulator-like actions. What makes neuromodulation an important consideration is that it appears to be a fundamental process in modifying all aspects of neural network functioning and information processing. Neural networks are not hard-wired, but plastic, and the neuromodulation of its components yields distinct activity patterns that are associated with behavioral state, allowing the same neural circuit to have added computational power.