Interplay between dopamine and acetylcholine in the modulation of attention Chapter uri icon

abstract

  • Attention involves several functions such as alertness, shift, stabilization, and distractor suppression. Alertness is a global mental state characterized by increased motivation and lowered thresholds for encoding new information. Attention shift allows either transiting from a passive inattentive to an active focused state, or refocusing perceptual resources from a previously targeted perceptual object to a more salient one. During attention stabilization perceptual resources are kept concentrated onto a particular target in a manner that the neural activity evoked by selected stimuli is momentarily enhanced. Suppression is an active process by which neural activity evoked by task irrelevant stimuli is diminished. These functions are impaired in several neuropsychiatric conditions. We review clinical and neurophysiological data in humans and laboratory animals suggesting that acetylcholine and dopamine interact in the neocortex to produce purposeful attention. It is proposed that a more satisfactory theory of attention needs to integrate both tonic and phasic effects produced by acetylcholine and dopamine. In the model here proposed, nicotinic receptors are thought to play a pivotal role in the enhancement of neural activity evoked by task relevant stimuli. Muscarinic receptors are proposed to be involved in alertness, and dopaminergic receptors in the temporary representation of intermediate goals. A combination of signals triggered by muscarinic and dopaminergic receptor coactivation may facilitate the suppression of neural activity evoked by task irrelevant stimuli. A better understanding of the interplay between dopamine and acetylcholine in attention modulation may help to develop better psychopharmacological interventions for neuropsychiatric conditions in which attention is impaired. © 2007 Springer Science%2bBusiness Media, LLC. All rights reserved.

publication date

  • 2007-01-01