Driving Performance of Drivers with Autism Spectrum Disorders: A Simulator Study

Background:  Driving is an important step for transitioning into adulthood as it cultivates a sense of autonomy and can help secure employment and social relationships. In order to be safe on the road, drivers are required to demonstrate a range of driving knowledge and skills related to traffic regulations, speed control, lane positioning, vehicle control, safe distance to others, anticipation and management of hazardous situations. Individuals with ASD often have more difficulties with executive functioning, which include processing speed, working memory, attention, mental flexibility, planning, and also difficulties in the ability to anticipate events. Due to the characteristics of autism and the nature of driving, driving can be challenging for drivers on the autism spectrum.

Objectives: This study aims to examine how drivers with Autism Spectrum Disorder perform during an unanticipated driving scenario in comparison with neurotypical drivers using a driving simulator.

Methods:  Seventeen drivers with Autism Spectrum Disorder and 18 drivers without underwent a driving simulation (STISIM M300WS) in an urban setting consisting of a critical driving scenario. Driving mistakes and performance outputs on the driving simulator and the self-reported driving history on the Driving Behaviour Questionnaire were analysed.

Results: Drivers with Autism Spectrum Disorder reported significantly more lapses on the Driving Behaviour Questionnaire and committed more driving mistakes on the driving simulator than drivers without. Drivers with Autism Spectrum Disorder were also slower to react to the abrupt changes in traffic lights. However, drivers with Autism Spectrum Disorder drove less closely to vehicles in front, measured by time to collision (TTC), and were less likely to tailgate other vehicles.

Conclusions:  Drivers with Autism Spectrum Disorder may be less efficient in responding promptly to critical driving scenarios that require prompt identification of and reaction to hazards but they appear to be safe drivers with respect to keeping distance to cars in front. Driver education should emphasise on the critical response of drivers with Autism Spectrum Disorder in different driving scenarios.