'I didn't see that coming': simulated visual fields and driving hazard perception test performance.

Area of Science:

• Ophthalmology
• Human Factors Engineering
• Transportation Safety

Background:

• Limited evidence exists on how specific visual field defects impact driving safety.
• Driving impairment due to visual field loss is a significant public health concern.

Purpose of the Study:

• To investigate the effect of simulated visual field loss on driving hazard detection.
• To assess the impact of scotomata (blind spots) located to the right and left of visual fixation on driving performance.

Main Methods:

• Utilized a novel gaze-contingent software (GazeSS) to simulate visual field defects during a computer-based hazard perception test.
• Thirty healthy drivers completed the UK driving licence examination's hazard perception test under three conditions: normal vision, simulated left scotoma, and simulated right scotoma.

Main Results:

• Simulated visual field loss significantly reduced hazard detection scores compared to baseline performance (p=0.007).
• No significant average difference in performance was observed between simulated scotomata located to the left versus the right of fixation.
• Specific types of hazards proved more challenging under simulated visual field loss conditions.

Conclusions:

• Simulated visual field loss negatively impacts the ability to detect driving hazards in a computer-based assessment.
• The location of a simulated scotoma (left vs. right of fixation) did not differentially affect overall driving hazard detection performance.
• Further research is needed to identify specific hazards that pose greater risks to drivers with visual field loss.