title: Neuronal effects of nicotine during auditory selective attention.
abstract: BACKGROUND
  Although the attention-enhancing effects of nicotine have been behaviorally and neurophysiologically well-documented, its localized functional effects during selective attention are poorly understood.
  
  
  OBJECTIVE
  In this study, we examined the neuronal effects of nicotine during auditory selective attention in healthy human nonsmokers. We hypothesized to observe significant effects of nicotine in attention-associated brain areas, driven by nicotine-induced increases in activity as a function of increasing task demands.
  
  
  METHODS
  A single-blind, prospective, randomized crossover design was used to examine neuronal response associated with a go/no-go task after 7 mg nicotine or placebo patch administration in 20 individuals who underwent functional magnetic resonance imaging at 3T. The task design included two levels of difficulty (ordered vs. random stimuli) and two levels of auditory distraction (silence vs. noise).
  
  
  RESULTS
  Significant treatment × difficulty × distraction interaction effects on neuronal response were observed in the hippocampus, ventral parietal cortex, and anterior cingulate. In contrast to our hypothesis, U and inverted U-shaped dependencies were observed between the effects of nicotine on response and task demands, depending on the brain area.
  
  
  CONCLUSIONS
  These results suggest that nicotine may differentially affect neuronal response depending on task conditions. These results have important theoretical implications for understanding how cholinergic tone may influence the neurobiology of selective attention.
authors.affiliation: Research Service, Denver VA Medical Center, Denver, CO, USA, jason.smucny@ucdenver.edu.
authors.forename: Jason
authors.initials: J
authors.lastname: Smucny
authors.forename: Ann
authors.initials: A
authors.lastname: Olincy
authors.forename: Lindsay S
authors.initials: LS
authors.lastname: Eichman
authors.forename: Jason R
authors.initials: JR
authors.lastname: Tregellas
mesh_terms: D000279:Administration, Cutaneous; D000328:Adult; D001288:Attention / Q000187:drug effects*; D001307:Auditory Perception / Q000187:drug effects*; D001921:Brain / Q000187:drug effects*; D001931:Brain Mapping; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009474:Neurons / Q000187:drug effects; D009538:Nicotine / Q000494:pharmacology*; D011446:Prospective Studies; D016037:Single-Blind Method
chemical_list: D009538:Nicotine