Noise and attentional selectivity: A reproducible phenomenon?

It has been suggested that loud noise increases attentional selectivity. Hockey (19706) found that noise improved performance on the high priority aspects of a complex task and found a corresponding impairment on the low priority aspects of the task. An alternative explanation was offered by Poulton (1976) who suggested that noise impairs performance by masking auditory feedback from subjects’ responses. Four experiments were carried out in order to investigate the phenomenon. No evidence of impaired performance was found in any of the four experiments, with or without auditory feedback. Thus, neither attentional selectivity nor masking of auditory feedback was found to be a significant factor in these experiments. It was concluded that this task is not suitable for investigating the effects of noise on attentional selectivity. The mechanisms underlying behavioural changes in response to high-intensity sound are not well understood despite an extensive experimental literature. This is in part due to differences in the type of noise used, in the nature of the task, and in measures of performance. These have produced conflicting and often contradictory findings. Noise can be shown to produce either an increment (McGrath, 1960), a decrement (Jerison, 1959), or have no effect on performance (Davies & Hockey, 1966). A further complication is provided by the various theoretical accounts of noise effects, which influence both the design of experiments and the interpretation of results. One approach is to view high-intensity sound as a general exteroceptive stimulant which acts to raise the level of activation in the so-called ‘reticular arousal system’ (Hockey, 1970~). This view has some support from physiological (Anthony & Ackerman, 1955; Helper, 1957) and behavioural studies (Corcoran, 1962; Wilkinson, 1963) and allows application of the inverted-U-shaped arousal/performance function (Hebb, 1955; Malmo, 1959; Duffy, 1962) to the effects of noise. As the optimum level of arousal is held to be different for simple tasks than for complex tasks (Broadhurst, 1959), arousal theorists can account for the differential effects of noise in terms of task demands. performance most sensitive to arousal have not been clearly defined. One possible explanation is