Simulated car driving in fMRI--Cerebral activation patterns driving an unfamiliar and a familiar route.

Understanding the neuronal underpinnings of cognitive processes during car driving is essential to understanding the origin of automobile accidents. Using fMRI we aimed to reveal differences in activation distribution contrasting passively observing an unfamiliar versus a familiar route to analyse the importance of the degree of familiarity of a route on attention process. We developed a special driving simulation software known as "Mechanics & Traffic", which focuses on the physical properties of driving. Sixteen male police-academy students with special driving training were examined while passively watching the car on an unfamiliar route, following a training-period outside the scanner, and passively watching the car on the now familiar route. The driving task revealed activations in frontal, parietal, temporal, occipital lobes, the thalamus, and cerebellum. Direct comparison revealed significant activation for the unfamiliar route in the middle temporal and occipital cortex and in the cerebellum. Correlating activations with the influencing covariates of driving experience, the activation pattern was confirmed and an additional activation for the unfamiliar route was found in the inferior frontal and parahippocampal gyrus. The results give further evidence that driving a car is a complex cognitive skill. A training-period and a familiar, monotonous route seem to lead to a reduction in attention and perception processes which might be associated with a danger for commuters, even in specially trained drivers.