title: The effects of moderate alcohol concentrations on driving and cognitive performance during ascending and descending blood alcohol concentrations.
abstract: OBJECTIVE
  Alcohol has an adverse effect on driving performance; however, the effects of moderate doses on different aspects of the driving task are inconsistent and differ across the intoxication curve. This research aimed to investigate driving and cognitive performance asymmetries (acute tolerance and acute protracted error) accompanying the onset and recovery from moderate alcohol consumption.
  
  
  METHODS
  Sixty-one participants received a placebo, medium (target blood alcohol concentration [BAC] 0.05 mg/ml) or high (target BAC 0.08 mg/ml) dose of alcohol. Participants completed a simulated drive, cognitive tests and subjective rating scales five times over a 3.5 h period.
  
  
  RESULTS
  When ascending and descending BACs (0.05 and 0.09 mg/ml) were compared participants' self-ratings of intoxication and willingness to drive showed acute tolerance. Acute protracted errors were observed for response speed, maze learning errors, time exceeding the speed limit and exaggerated steering responses to hazards.
  
  
  CONCLUSIONS
  Participants' estimates of their level of intoxication were poorly related to their actual BAC levels (and hence degree of impairment), and various aspects of driving and cognitive performance worsened during descending BACs. This indicates that drivers are not good at judging their fitness to drive after drinking only moderate amounts of alcohol and suggests an important focus for public education regarding alcohol and driving.
authors.affiliation: Traffic and Road Safety Research Group (TARS), School of Psychology, The University of Waikato, Hamilton, New Zealand.
authors.forename: Nicola J
authors.initials: NJ
authors.lastname: Starkey
authors.forename: Samuel G
authors.initials: SG
authors.lastname: Charlton
mesh_terms: D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects* / Q000097:blood / Q000523:psychology*; D000435:Alcoholic Intoxication / Q000097:blood / Q000523:psychology; D001334:Automobile Driving / Q000523:psychology; D001944:Breath Tests; D002492:Central Nervous System Depressants / Q000008:administration & dosage / Q000009:adverse effects; D003071:Cognition / Q000187:drug effects*; D000431:Ethanol / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011581:Psychological Tests; D011597:Psychomotor Performance / Q000187:drug effects*; D011930:Reaction Time / Q000187:drug effects; D014584:User-Computer Interface; D055815:Young Adult
chemical_list: D002492:Central Nervous System Depressants; D000431:Ethanol
keywords: acute protracted error; acute tolerance; alcohol; cognitive performance; driving; subjective intoxication