A new study by UTS medical scientists comparing the driver behaviour of older and younger drivers has shown health and lifestyle rate with age and experience as risk factors on the road.
The study, which put drivers aged from 17 to 68 through their paces in a simulator while recording their brain activity and cardiovascular responses, also found that the over 25s were subject to more risk factors leading to driving errors than the under 25s.
Dr Sara Lal, who supervised Bachelor of Medical Science (Honours) student Laarnie Pe Benito in the research, said the neurophysiological lab-based assessment had highlighted several issues "relatively untouched" in previous studies based largely on questionnaires.
"We know that an increase in slow wave brain activity signals the onset of drowsiness and that the same sort of brain activity is seen in people affected by alcohol and those affected by sleep apnoea," Dr Lal said. "Driving with sleep apnoea, then, is effectively the same as drink driving."
A group of 74 subjects, 40 under 25 and 34 over 25, were tested and questioned for the study. They were asked to drive the simulator to the point of fatigue and subjected to distractions, such as talking to passengers or using a mobile phone. Results were collated based on the virtual driving errors recorded in conjunction with the neurophysiological data.
Ms Pe Benito said the results defied some of the conventional wisdom about the differences between young and more seasoned drivers.
"For young drivers we found that the strongest predictors of crashing were body mass index (BMI) and regular alcohol consumption – as distinct from driving under the influence of alcohol," she said.
"Obesity is a significant risk factor shared with older drivers. High BMI goes hand-in-hand with increased levels of lethargy, the rapid onset of fatigue and slower reaction times.
"Age and experience also were identified as risk factors, but the issue of driving experience was not confined to the young. We have found that people who have obtained a driving licence later in life are more at risk of having an accident than inexperienced younger drivers.
"Interestingly older drivers were more sensitive to lifestyle factors, like smoking and emotional stress, and were found to take part in more risky driving behaviour.
"However, there was no significant difference in brain activity and mood between young and older drivers and no association found between mood and driving performance," Ms Pe Benito said.
Editor's Note: Original news release can be found here.