Impaired Curve Negotiation in Drivers with Parkinson’s Disease

OBJECTIVE: To assess the ability to negotiate curves in drivers with Parkinson’s disease (PD).
METHODS: Licensed active drivers with mild-moderate PD (n= 76; 65 male, 11 female) and elderly controls (n= 51; 26 male, 25 female) drove on a simulated 2-lane rural highway in a high-fidelity simulator scenario in which the drivers had to negotiate 6 curves during a 37-mile drive. The participants underwent motor, cognitive, and visual testing before the simulator drive.
RESULTS: Compared to controls, the drivers with PD had less vehicle control and driving safety, both on curves and straight baseline segments, as measured by significantly higher standard deviation of lateral position (SDLP) and lane violation counts. The PD group also scored lower on tests of motor, cognitive, and visual abilities. In the PD group, lower scores on tests of motion perception, visuospatial ability, executive function, postural instability, and general cognition, as well as a lower level of independence in daily activities predicted low vehicle control on curves.
CONCLUSION: Drivers with PD had less vehicle control and driving safety on curves compared to controls, which was associated primarily with impairments in visual perception and cognition, rather than motor function