THE INFLUENCE OF ALCOHOL ON ODOR DETECTION*

Abstract. A signal detection experiment showed that human subjects whose blood alcohol level was approximately 70 mg % were more sensitive to a 'burnt ' odor (guaicol) than control subjects. The most plausible explanation for this finding seems to be that alcohol affects the accessibility of odorous molecules at the olfactory epithelium. It is usually assumed that alcohol will affect a person's perceptual ability adversely. For example, it has been suspected that an intoxicated person may be less sensitive to smoke than a sober person and thus more likely to become asphyxiated before awakening. One report (Margulies et ah, 1950), apparently the only one on the topic, claims that only 75 ml of 12 % of alcohol produced a decrement in odor sensitivity. Unfortunately, the reliability of the effect was not assessed. A possible alternative explanation of such a finding is that alcohol affects a person's attitude or ability as to judge such that he performs differently in the task when intoxicated than when sober, although he may be just as sensitive physiologically. The psychological state of the subject must be measured independently of his sensitivity or acuity. The present experiment is related to an earlier one (Engen, 1972) which assessed the bias in reporting the experience of odor in the presence of visual signals. For this reason the present experiment observed the effect of alcohol on (a) the subject's psychological state in terms of his tendency to make false alarms, that is, report the experience of a burnt odor when none has been presented, and on (b) his acuity as indicated by his ability to detect the odor when it was actually presented