Alcohol effects on human risk taking.
BACKGROUND
Despite a well-established relationship between alcohol and risky behavior in the natural environment, laboratory investigations have not reliably shown acute alcohol effects on human risk-taking.


OBJECTIVE
The present study was designed to demonstrate a dose-response relationship between acute alcohol administration and human risk taking. Further, this investigation sought to delineate behavioral mechanisms that may be involved in alcohol-induced changes in the probability of risky behavior.


METHODS
Using a laboratory measure of risk taking designed to address acute drug effects, 16 adults were administered placebo, 0.2, 0.4, and 0.8 g/kg alcohol in a within-subject repeated measures experimental design. The risk-taking task presented subjects with a choice between two response options operationally defined as risky and non-risky. Data analyses examined: breath alcohol level (BAL), subjective effects, response rates, distribution of choices between the risky and non-risky option, and trial-by-trial probabilities of making losing and winning risky responses.


RESULTS
The alcohol administration produced the expected changes in BAL, subjective effects, and response rate. Alcohol dose-dependently increased selection of the risky response option, and at the 0.8 g/kg dose, increased the probability of making consecutive losing risky responses following a gain on the risky response option.


CONCLUSIONS
Acute alcohol administration can produce measurable changes in human risk-taking under laboratory conditions. Shifts in trial-by-trial response probabilities suggest insensitivity to past rewards and more recent losses when intoxicated, an outcome consistent with previous studies. This shift in sensitivity to consequences is a possible mechanism in alcohol-induced changes in risk taking.
Lane
Scott D
SD
Psychiatry and Behavioral Sciences, The University of Texas Health Science Center-Houston, 1300 Moursund Street, Houston, TX 77030, USA. scott.d.lane@uth.tmc.edu
Cherek
Don R
DR
Pietras
Cynthia J
CJ
Tcheremissine
Oleg V
OV
D000328:Adult; D001944:Breath Tests; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D012309:Risk-Taking
D000431:Ethanol