NOISE AND HUMAN PERFORMANCE, A PSYCHOPHYSIOLOGICAL APPROACH

Abstract

A theoretical approach is developed for the study of the effects of noise on human performance which takes into account the psychological factors of distraction and habituation and the physiological factors of auditory adaptation and bodily arousal. Two experiments designed to test theoretical predictions suggested that the approach is reasonable. Distraction studied in terms of changes in ambient noise levels was found to be a function of the amount of change. When adaptation of the ear is controlled by use of on-off sound sequences, ignoring distraction, performance is directly related to the on-off ratio early in exposure and inversely related to the ratio later in exposure. At all sound ratios performance in noise is better than in quiet. When distraction is taken into account, these results are influenced by the differences in rate and amount of adaptation of loudness and rate of habituation to distraction so that at any given time performance may seem to be decreased, increased or unaffected.