title: Meta-analysis of the acute effects of nicotine and smoking on human performance.
abstract: OBJECTIVE
  Empirical studies indicate that nicotine enhances some aspects of attention and cognition, suggesting a role in the maintenance of tobacco dependence. The purpose of this review was to update the literature since our previous review (Heishman et al. Exp Clin Psychopharmacol 2:345-395, 1994) and to determine which aspects of human performance were most sensitive to the effects of nicotine and smoking.
  
  
  METHODS
  We conducted a meta-analysis on the outcome measures of 41 double-blind, placebo-controlled laboratory studies published from 1994 to 2008. In all studies, nicotine was administered, and performance was assessed in healthy adult nonsmokers or smokers who were not tobacco-deprived or minimally deprived (<or=2 h).
  
  
  RESULTS
  There were sufficient effect size data to conduct meta-analyses on nine performance domains, including motor abilities, alerting and orienting attention, and episodic and working memory. We found significant positive effects of nicotine or smoking on six domains: fine motor, alerting attention-accuracy and response time (RT), orienting attention-RT, short-term episodic memory-accuracy, and working memory-RT (effect size range = 0.16 to 0.44).
  
  
  CONCLUSIONS
  The significant effects of nicotine on motor abilities, attention, and memory likely represent true performance enhancement because they are not confounded by withdrawal relief. The beneficial cognitive effects of nicotine have implications for initiation of smoking and maintenance of tobacco dependence.
authors.affiliation: Nicotine Psychopharmacology Section, National Institute on Drug Abuse, NIH Intramural Research Program, 251 Bayview Blvd., Baltimore, MD 21224, USA. heishman@nih.gov
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Heishman
authors.forename: Bethea A
authors.initials: BA
authors.lastname: Kleykamp
authors.forename: Edward G
authors.initials: EG
authors.lastname: Singleton
mesh_terms: D001288:Attention / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008568:Memory / Q000187:drug effects; D009048:Motor Skills / Q000187:drug effects; D009538:Nicotine / Q000008:administration & dosage / Q000494:pharmacology*; D011597:Psychomotor Performance / Q000187:drug effects*; D012907:Smoking / Q000523:psychology*
chemical_list: D009538:Nicotine