Factors affecting the perception of intoxication: dose, tolerance, and setting.

The present experiment was designed to investigate whether changes in internal sensations and affect are used to discriminate intoxication and to determine how the discriminability of these cues is affected by dose, acquired tolerance, and the setting in which alcohol is consumed. Setting varied according to whether subjects were distracted or not distracted from attending to alcohol induced changes. Furthermore, subjects drank either a placebo beverage or one of two doses of alcohol. The results showed an interaction between dose and setting, which suggested that subjects who participated in a distracting task were less accurate in the evaluation of their intoxication and were more easily misled into believing that they had consumed alcohol when they had actually received a placebo. Additional measures suggested that the distracted subjects did not base their intoxication ratings as closely on changes associated with alcohol consumption. Acquired tolerance to alcohol also affected the perception of intoxication and influenced the discriminability of changes in internal sensations and affect. The findings on tolerance are related to motives for increasing alcohol consumption over time and to the inefficacy of blood alcohol level discrimination training with alcoholics.