Acute alcohol effects on subtypes of impulsivity and the role of alcohol-outcome expectancies

Psychopharmacology (Berl). 2013 Sep;229(1):21-30. doi: 10.1007/s00213-013-3079-8. Epub 2013 Apr 12.


Rationale: It is well established that alcohol acutely impairs the ability to inhibit a pre-potent response (motor impulsivity), but its effects on cognitive impulsivity, including temporal (delayed gratification) and reflection (decision making) impulsivity, are not clear. An important factor contributing to the effects of alcohol is cognitive expectancies of alcohol-related outcomes.

Objectives: The current study investigated the effect of alcohol, and alcohol outcome expectancies, on subtypes of impulsivity.

Methods: Impulsivity was tested using the Stop Signal, the Single Key Impulsivity and the Information Sampling Task for motor, temporal and reflection impulsivity, respectively. Participants (n = 48) received placebo, a low (0.4 g/kg) or high dose (0.8 g/kg) of alcohol, before completing the impulsivity measures.

Results: Motor impulsivity was affected by alcohol dose; participants receiving a high dose displayed reduced inhibitory control. Reflection impulsivity was affected by cognitive alcohol expectancies, but not by alcohol condition; participants expecting greater cognitive and behavioural impairment by alcohol exhibited low impulsivity. Temporal impulsivity was not affected by either alcohol dose or outcome expectancies.

Conclusions: These data suggest that the effects of alcohol on the subtypes of impulsivity are dissociable. Motor impulsivity is sensitive to the pharmacological effects of alcohol, whereas the reflection subtype is affected by cognitive alcohol expectancies. The findings have implications for the understanding of impulsive behaviour under the influence of alcohol.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Alcohol Drinking / psychology*
  • Double-Blind Method
  • Ethanol / administration & dosage*
  • Ethanol / adverse effects
  • Female
  • Humans
  • Impulsive Behavior / chemically induced*
  • Impulsive Behavior / psychology*
  • Male
  • Psychomotor Performance / drug effects*
  • Psychomotor Performance / physiology
  • Surveys and Questionnaires
  • Time Factors
  • Young Adult


  • Ethanol