With the present introduction of commercially available systems that support drivers in their navigation task the question can be posed how such systems should present their information. The literature suggests an advantage for auditory over visual information because the visual channel is already heavily loaded while driving. In addition, earlier research has shown that verbal guidance instructions, which can be best presented auditorily, yields better performance than symbolic spatial instructions like arrows, which have to be presented visually. The major aim of the present study was to replicate this finding and to test explanations for it. The results in this study showed, indeed, better performance of verbal over spatial instructions. They suggest that the advantage of verbal instructions was caused by the need for additional information processing of spatial instructions which was not required for verbal instructions. This extra processing would take place after the road scene with the indicated side-roads is perceived. It is, therefore, suggested that navigation instructions should primarily be presented in auditory verbal format and not as spatial symbolic instructions. (Author/publisher)
Abstract