There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
Unitary concepts of arousal have outlived their usefulness and their psychological
fractionation corresponds to a similar chemical differentiation of the reticular formation
of the brain. Neurobiological characteristics of the monoaminergic and cholinergic
systems can be described in terms of their anatomical, electrophysiological and neurochemical
properties. Functional studies suggest that the coeruleo-cortical noradrenergic system,
under certain circumstances, is implicated in processes of selective attention, that
the mesolimbic and mesostriatal dopaminergic systems contribute to different forms
of behavioural activation, and that the cortical cholinergic projections have fundamental
roles in the cortical processing of signals, affecting attentional and mnemonic processes.
The ascending serotoninergic systems contribute to behavioural inhibition and appear
to oppose the functions of the other systems in several ways.