Visual motion perception and driving hazard visibility at night-time

Motion perception is an important visual process involved in driving, and has been associated with daytime driving performance, however, few studies have investigated the association of motion perception with night driving. This study examined the relationship between motion perception and performance on a computer-based off-road Night-time Hazard Visibility Test (NHVT) in 70 licensed drivers (M = 53.4 ± 23.9 years; 18-84 years), with and without eye disease. Motion perception was tested binocularly on four motion tasks: minimum displacement thresholds (D_min), minimum contrast and minimum velocity of a drifting Gabor, and motion surround suppression based on minimum duration of a high-contrast Gabor using two Gabor sizes. Participants also completed chart-based measures of visual acuity and contrast sensitivity under photopic and mesopic conditions and hazard response times measured using the NHVT. In bivariate linear regression models, poorer motion perception thresholds for all tests were associated with delayed NHVT response times (p ≤ 0.006). In multivariate models, only D_min remained independently associated with NHVT response times, when adjusted for chart-based tests (p ≤ 0.016). Our results provide new insight into aspects of motion perception important for night-time hazard detection, with inter-individual variability in ability to detect small motion displacements being important for rapid identification of moving hazards in night driving scenes.