Visual search of driving situations: Danger and experience

Previous research on visual search in driving suffers from a number of prob lems: small sample sizes, a concentration on mundane situations, and a fail ure to link results to more general psychological theory. The study reporte d in this paper addresses these issues by recording the eye movements of a large sample of drivers while they watched films of dangerous driving situa tions and comparing the findings with those from more general studies on sc ene perception. Stimuli were classified according to the types of road show n and the degree of danger present in the scenes. Two groups of subjects to ok part, fifty-one young novice drivers who had just gained a full driving licence and twenty-six older more experienced drivers. Dangerous situations were characterised by a narrowing of visual search, shown by an increase i n fixation durations, a decrease in saccade angular distances, and a reduct ion in the variance of fixation locations. These effects are similar to the concept of 'attention focusing' in traumatic situations as it is described in the literature on eyewitness memory. When road types are compared, the least visually complex rural roads attracted the longest fixation durations and the shortest angular saccade distances, while the most visually comple x urban roads attracted the greatest spread of search but the shortest fixa tion durations. Differences between the groups of subjects were also presen t. Novices had longer fixation durations than experienced drivers, particul arly in dangerous situations. Experienced drivers also fixated lower down a nd had less vertical Variance in fixation locations than novices.