title: A diffusion model decomposition of the effects of alcohol on perceptual decision making.
abstract: BACKGROUND
  Even in elementary cognitive tasks, alcohol consumption results in both cognitive and motor impairments (e.g., Schweizer and Vogel-Sprott, Exp Clin Psychopharmacol 16: 240-250, 2008).
  
  
  OBJECTIVE
  The purpose of this study is to quantify the latent psychological processes that underlie the alcohol-induced decrement in observed performance.
  
  
  METHODS
  In a double-blind experiment, we administered three different amounts of alcohol to participants on different days: a placebo dose (0 g/l), a moderate dose (0.5 g/l), and a high dose (1 g/l). Following this, participants performed a "moving dots" perceptual discrimination task. We analyzed the data using the drift diffusion model. Model parameters drift rate, boundary separation, and non-decision time allow a decomposition of the alcohol effect in terms of their respective cognitive components, that is, rate of information processing, response caution, and non-decision processes (e.g., stimulus encoding, motor processes).
  
  
  RESULTS
  We found that alcohol intoxication causes higher mean RTs and lower response accuracies. The diffusion model decomposition showed that alcohol intoxication caused a decrease in drift rate and an increase in non-decision time.
  
  
  CONCLUSIONS
  In a simple perceptual discrimination task, even a moderate dose of alcohol decreased the rate of information processing and negatively affected the non-decision component. However, alcohol consumption left response caution largely intact.
authors.affiliation: Department of Psychology, University of Amsterdam, Roetersstraat 15, 1018 WB, Amsterdam, The Netherlands. d.vanravenzwaaij@uva.nl
authors.forename: Don
authors.initials: D
authors.lastname: van Ravenzwaaij
authors.forename: Gilles
authors.initials: G
authors.lastname: Dutilh
authors.forename: Eric-Jan
authors.initials: EJ
authors.lastname: Wagenmakers
mesh_terms: D000293:Adolescent; D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects*; D000435:Alcoholic Intoxication / Q000503:physiopathology; D003071:Cognition / Q000187:drug effects; D003657:Decision Making / Q000187:drug effects*; D004193:Discrimination Learning / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D000431:Ethanol / Q000008:administration & dosage / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008960:Models, Psychological; D010865:Pilot Projects; D011930:Reaction Time / Q000187:drug effects; D013997:Time Factors; D055815:Young Adult
chemical_list: D000431:Ethanol