NO EFFECT OF NOISE ON VIGILANCE PERFORMANCE

The effects of intermittent noise and its temporal pattern on visual vigilance performance were investigated using a between-subjects design with a multivariate approach. The conventional way of analyzing the data showed a decrement in sensitivity with time on task, a rise in false alarms, but no significant effect of noise. However, a detailed analysis demonstrated a facilitatory effect of the noise stimuli, which may be explained in terms of orienting reaction theory. It is suggested that the usual way of analyzing data from vigilance experiments may veil the effects of independent variables, such as noise. Some sex differences in performance were also noted. An additional estimation task provided no support for expectancy theory.