A comparison was made of the attention-demanding values of auditory stimuli differing in frequency, and of visual stimuli differing in wave length under different conditions of background noise. Following a survey of the literature, a method was developed which was intended to provide a laboratory analogue of real tasks and which lent itself to measurements of stimulus-effectiveness in attracting the attention of the subject. Quantitative measures could now be obtained both by threshold techniques and reaction time techniques.nWith respect to the practical problem of designing systems of warning signals, the results indicate that engineers and engineering psychologists are justified in utilizing the substantial body of knowledge already established concerning sensory thresholds, and their dependence on frequency, as a guide in the selection of stimuli to be used as warning signals. No statistically significant change in the form of sensory threshold curves results from distraction of the individual by a task.
展开▼
