Spatial navigation ability and gaze switching in older drivers: A driving simulator study.

Objective: Driving ability in older people is affected by declining motor, cognitive and visual functions. We compared perceptual and cognitive skills and driving behaviour in a Japanese population.

Methods: We used a driving simulator to measure the effects of spatial navigation skills and eye movements on driving ability. Participants were 34 older and 20 young adults who completed a simulated driving task involving a lane change and a right turn at an intersection. We used an eye tracker to measure gaze. We measured visual recognition (Benton Judgment of Line Orientation Test (BJLO)), spatial navigation (Card-Placing Test (CPT A & B)), visual perception (Raven's Colored Progressive Matrices (RCPM)) and driving ability (Stroke Drivers' Screening Assessment).

Results: Older participants scored significantly lower on the BJLO, CPT-A & B and RCPM, showed a significant correlation between gaze time and CPT-A & B scores (both p < .01) and had a longer gaze time. There were significant between-group differences in saccade switching (p < .01 right turn), distance per saccade (p < .05 for right turn and lane change) and saccade total distance (p < .05 right turn; p < .01 lane change). There was an association between age and rate of gaze at the right door mirror (p = 0.04).

Conclusion: The findings indicate that older drivers have poorer eye movement control and spatial navigation. This is likely to result in delayed responses and difficulties in predicting the on-coming driving environment. Driving simulation could help older drivers in their driving abilities.