Neuropsychological aspects of driving after brain lesion: simulator study and on-road driving.

Twenty-nine patients with brain lesion and 29 matched controls participated in the study. The patients were socially well recovered with a high rate of employment. Compared with the controls, they performed significantly worse on a neuropsychological test battery, especially on executive and cognitive functions. Patients drove as well as controls in predictable situations in the advanced simulator used. In unpredictable situations, they demonstrated longer reaction times and safety margins, as well as difficulties in allocating processing resources to a secondary task. The patients showed significantly less attention, worse traffic behavior, and less risk awareness when driving in real traffic. Forty-one percent of the patients did not pass the driving test. The neuropsychological test battery was factor analyzed into four factors: executive capacity, cognitive capacity, automatic attentional capacity, and simple perceptual-motor capacity. The second factor was the mast significant with a simultaneous capacity test predicting driving performance with 78% confidence.