Drivers With Vision Defects And Their Impact On Eye Movement Patterns - Evidence For Safe Driving

Neryla Jolly, Hamish MacDougall & Robert Heard

An important component of vision in the driving situation are eye fixation movements which feed back information to assist the driver to gain vehicle control through guiding steering and vehicle position, and helping with the identification of risky situations. Reduced vision is understood to lead to problems with the above skills as well as detecting other vehicles, pedestrians and hazards. Logically vision defects cause a change in fixation movements, reduced vision feedback and increased risk in the driving situation, resulting in accidents.

The aim of this research is to compare the eye fixation movements in fully sighted drivers with drivers who have vision defects.

Method: Drivers were tested in two situations in a simulator or on road. In both situations the eye fixation movements were recorded, using eye tracking goggles. The simulator was used in order to provide consistency and repeatability of a route and driving environment pattern. This incorporated a software program with images of an on road driving experience projected onto a screen. The driver, seated in a real stationary car, navigated to reach a set destination in as short and safe a time as possible.

Where drivers were licensed to be tested on road and for some drivers on a private driving track, the eye fixation movements were recorded whilst the driver navigated a pre determined route. Consistency could only be maintained by using, the same route, a similar vehicle, similar lighting conditions and consistent accompanying passengers. Variability in traffic conditions was uncontrolled.

To enable best comparison the outcomes for 5 on road situation segments were selected. Each was chosen because it related to high accident situations. The eye fixation patterns for the simulator and on road drive were compared for driver with full vision and drivers with visual field defects.

Outcomes: Initial outcomes have revealed that for fully sighted drivers there is high agreement in eye fixation patterns between the simulator and on road for driving some tasks. Results will be presented for drivers with peripheral vision loss which has been long standing and recent. Some of the drivers with long standing vision loss have been driving with the defect for many years.