Abstract
Safely responding to a road hazard and avoiding a crash requires knowing when the hazard occurs and where it is in the scene. Cueing attention to the hazard’s location speeds localization in naturalistic road videos, whereas invalid spatial cues slow localization (Wolfe et al., 2021). Since any alerting technology will be imperfect, invalid spatial cues produced in error are particularly dangerous on the road. Temporal cues (telling a driver when a hazard occurs) may be a more useful alternative, but it is unclear what cue-hazard timings are effective. Here, we investigated the effect of auditory cue timing on the speed and accuracy of hazard localization using a set of naturalistic driving videos showing real road hazards. Thirty licensed drivers aged 18-25 watched brief road videos lasting 2-8 seconds. Each video contained an annotated hazard that occurred at an unpredictable time before the end of the video. Observers indicated whether the hazard appeared on the left or right half of the screen. The auditory cue was presented at one of four times relative to hazard onset: -500ms, -250ms, 0ms, and 100ms (after hazard onset). Across all cue timing conditions, mean hazard localization accuracy exceeded 90%, and reaction times were significantly faster when a cue was present compared to a no-cue baseline (t >= 4.5, p <= 0.001 in each case). Hazards were localized faster when cues preceded the hazard, with the fastest reaction times in the -500ms condition (-500ms: M = 77ms, SE = 37ms vs. 0ms: M = 289ms, SE = 25ms; t = 6.46, p < 0.001). These results suggest that non-spatial auditory cues that are heard earlier (up to 500ms before the situation) help to orient attention to road hazards, even in the absence of specific location information in the cue.