This paper reviews the literature on the effects of low alcohol doses, and attempts to overcome the defects of previous reviews. A new classification system is proposed, which first distinguishes between subjective and objective features. Subjective features are subdivided into: (1) main effects, including positive mood and social feelings; (2) side effects, including feeling intoxicated. Objective effects are subdivided into: (1) performances, including automatic and controlling behaviour, and driving; (2) physiological and psychological functions; (3) interactive behaviour, including social and expressive behaviour. The material and methodology of the literature review are presented. Some results are reviewed on the `social window' of alcohol action and the objective effects of alcohol, including performance impairment. The following effects on performance are discussed: (1) psychophysical functions; (2) automatic processing; (3) control actions; (4) effects on driving; (5) modification of effect by time after drinking. Some consequences for legislation are indicated. The review shows that important psychophysical functions, including driving, are probably generally endangered only for blood alcohol concentration (BAC) levels of at least 0.07% to 0.08%. For any BAC below this limit, there are many functions and conditions where no noticeable impairment occurs.
Abstract