Abstract
Being able to divide attention across different tasks when driving, such as controlling speed and lane position, searching for hazards as well as listening to commands from in-vehicle assistance systems relies on timely allocation of cognitive resources. People with impaired vision (VI e.g., visual acuity as low as 20/200) may drive on a restricted license in some states and are likely to use driver assistance systems. However, the effects and interaction of VI and auditory distraction on the detection of hazards have not previously been examined. To address this gap in the literature, the current study evaluated the effects of simulated VI and auditory distraction on the detection of pedestrians in a driving simulator. Central vision loss was simulated in young normally-sighted subjects by goggles with diffusing filters that degraded both visual acuity (20/90 with and 20/20 without goggles) and contrast sensitivity (1.44 with and 1.77 log units without goggles). Auditory task demand was manipulated by playing audiobook excerpts and instructing subjects to listen for and repeat out loud two predetermined words. Subjects completed 4 highway drives (60 mph) in counterbalanced order (1) without simulated VI and without distraction; (2) with simulated VI and without distraction, (3) without simulated VI and with distraction; and (4) with simulated VI and with distraction. Subjects pressed the horn each time they saw a pedestrian hazard. Neither simulated VI nor distraction affected detection rates. However simulated VI substantially increased RTs by around 600ms. With the addition of audio distraction, RTs increased further and detection timeliness (detected in time to avoid a collision) decreased to only 70%. Combined simulated VI and distraction substantially increased the likelihood of a potential collision in young drivers. In the next phase of the project we will recruit older drivers to test the interactions between age, simulated VI and distraction.
Meeting abstract presented at VSS 2018