Oculomotor changes due to road events during prolonged monotonous simulated driving.

The possible influence of occuring external events on driver attention and vigilance level was assessed during a prolonged simulated driving task. Special attention was given to the duration of the task, as well as to the influence of time of day and of individual factors. Thirty six subjects drove for two hours. Blinking activity and eye movements associated with glances to the speedometer were recorded during the entire driving task and particularly during specific road events. During significant events, blinking and ocular activity decreased, attesting a higher attention of the driver. With increased duration of driving, the reduction in blinking and ocular activity was progressively smaller for the less significant events, indicating a reduction in attention. During driving, women blinked more frequently than men. With increased duration of driving, drivers adopted different behavioural strategies depending on their age and sex to reach a safe and adapted method of driving.