Three experiments are reported; two compare the attention demanded by visual and auditory road information, the third examines the effects on peripheral vision of monitoring auditory messages of various levels of complexity. The first study demonstates a much greater decrement in peripheral vision when road information is visual rather than auditory. The second study shows that drivers may slow down when listening to auditory messages but that their tracking does not deteriorate; whereas for visual messages there is a greater drop in speed and tracking errors increase. The third study suggests that very simple auditory messages may have a small but significant effect on tracking skill but no effect on peripheral vision; as the complexity of the message increases marked decrements occur in peripheral vision. On the basis of these studies it is suggested that although messages may impair driving performance, this decrement will be substandtially less than that associated with the same information presented visually.
Abstract