Executive function "drives" differences in simulated driving performance between young adults with and without autism spectrum disorder.

Individuals with autism spectrum disorder (ASD) may experience greater difficulty learning to drive than peers who do not have ASD, but reasons for those differences are unclear. This study examined how diagnostic symptoms of ASD and commonly co-morbid executive dysfunction relate to differences in simulated driving performance between young, inexperienced drivers with and without ASD. Participants included 98 young adults, ages 16-26 years, half of which were diagnosed with ASD. Participants with ASD completed the Autism Diagnostic Observation Schedule (ADOS-2) and self- and parent-report versions of the Social Responsiveness Scale (SRS-2) to confirm diagnosis and assess the severity of ASD symptoms. All participants completed neuropsychological tests measuring executive functioning. Driving behaviors, including speed and lane positioning, were assessed on a virtual reality driving simulator. Analyses were conducted to first examine relationships between autism severity and driving behaviors, and then to examine whether neurocognitive performance mediated differences in driving behaviors between young adults with and without ASD. Controlling for age, gender, and licensure status, ASD symptom severity was not significantly related to driving. Neurocognitive variables were grouped into three factors: Speed of Information Processing, Auditory Attention and Working Memory, and Selective and Divided Attention. Speed of Information Processing significantly mediated group driving differences. Results suggest that assessment of executive functions such as processing speed may be more useful than the diagnostic assessment of ASD symptoms for evaluation of driving readiness.