The effects of amblyopia on simulated driving behavior in an urban setting

To assess the driving performance and visual attention of amblyopic drivers using a driving simulator integrated with eye tracking technology in an urban setting.

A total of 30 participants were enrolled: 14 amblyopic patients (all anisometropic and one also with strabismus) and 16 controls. Participants completed a simulated urban driving task while their eye movements and driving performance were recorded using a DriveSafety DS-600c simulator integrated with an infrared eye tracker. Driving performance (speed, brake reaction time / deceleration at pedestrian crossings, lane position variability, steering variability) and eye movement parameters (fixations, gaze distribution, saccades) were compared between amblyopic and control participants. In addition, pooling data from both groups, we assessed for correlations between eye movement parameters and driving performance.

Amblyopic and nonamblyopic drivers performed similarly on driving tasks and had comparable eye movement recordings. Some nonsignificant tendencies were noted among amblyopic drivers, including slower driving speeds, longer brake reaction times, and increased steering variability. We identified potential tendencies for correlations between eye tracking metrics and driving performance: increased fixation frequency was associated with greater lane position variability, and larger saccadic movements correlated with improved lane stability and faster hazard response; however, these correlations were not statistically significant.

In our study cohort, simulated driving performance and attention in subjects with anisometropic amblyopia under a standardized, relatively low-complexity urban scenario were similar to findings for nonamblyopic drivers, suggesting that amblyopia did not prevent safe driving in that context. Trends toward correlations between eye tracking and driving simulation parameters were observed, underscoring the potential of combining both approaches in future research in addition to testing a larger sample size, with a more challenging driving scenario.