Abstract

This study reports the relationship between chronic sleep deficits and distractions on driving mistakes in
university undergraduates (age 19-23 years). All participants were asked to complete a questionnaire about
their sleeping habits and to drive a fixed-base driving simulator housed in a Fiat Cinquencento. Drivers were
distracted either by being asked to read a map, operate a radio, take a drink, open a sweet wrapper or discuss
with the experimenter (on a mobile phone during the drive).The results showed that drivers had more speed
limit exceedances and more road edge excursions when distracted. There was also a significant difference in
speed exceedances between participants who had sufficient sleep and those that had a chronic sleep debt.
Significant positive correlations were found between speed exceedance and obtaining too little sleep, and between feeling uncomfortable during the day in the distracted drivers. There was also a significant negative
correlation between speed exceedances and actual hours of sleep. Even when not distracted, a positive correlation existed between the number of collisions and difficulty in waking up. The results of this study indicate that young drivers with chronic sleep deficits are more likely to make driving errors when distracted.