title: Cholinergic receptor subtypes and their role in cognition, emotion, and vigilance control: an overview of preclinical and clinical findings.
abstract: BACKGROUND
  The cholinergic system has long been linked to cognitive processes. Two main classes of acetylcholine (ACh) receptors exist in the human brain, namely muscarinic and nicotinic receptors, of which several subtypes occur.
  
  
  OBJECTIVE
  This review seeks to provide an overview of previous findings on the influence of cholinergic receptor manipulations on cognition in animals and humans, with particular emphasis on the role of selected cholinergic receptor subtypes. Furthermore, the involvement of these receptor subtypes in the regulation of emotion and brain electrical activity as measured by electroencephalography (EEG) shall be addressed since these domains are considered to be important modulators of cognitive functioning.
  
  
  RESULTS
  In regard to cognition, the muscarinic receptor subtypes have been implicated mainly in memory functions, but have also been linked to attentional processes. The nicotinic α7 receptor subtype is involved in working memory, whereas the α4β2* subtype has been linked to tests of attention. Both muscarinic and nicotinic cholinergic mechanisms play a role in modulating brain electrical activity. Nicotinic receptors have been strongly associated with the modulation of depression and anxiety.
  
  
  CONCLUSIONS
  Cholinergic receptor manipulations have an effect on cognition, emotion, and brain electrical activity as measured by EEG. Changes in cognition can result from direct cholinergic receptor manipulation or from cholinergically induced changes in vigilance or affective state.
authors.affiliation: Department of Psychiatry, University of Leipzig, Semmelweisstr. 10, 04103 Leipzig, Germany. graef@cbs.mpg.de
authors.forename: Susanne
authors.initials: S
authors.lastname: Graef
authors.forename: Peter
authors.initials: P
authors.lastname: Schönknecht
authors.forename: Osama
authors.initials: O
authors.lastname: Sabri
authors.forename: Ulrich
authors.initials: U
authors.lastname: Hegerl
mesh_terms: D000818:Animals; D001143:Arousal / Q000502:physiology*; D001921:Brain / Q000378:metabolism*; D003071:Cognition / Q000502:physiology*; D004569:Electroencephalography; D004644:Emotions / Q000502:physiology*; D006801:Humans; D007858:Learning / Q000502:physiology; D019964:Mood Disorders / Q000378:metabolism; D011950:Receptors, Cholinergic / Q000145:classification / Q000502:physiology*
chemical_list: D011950:Receptors, Cholinergic