Performance of Drivers with Parkinson's Disease under the Effect of Cognitive Overloading: Insinuation for Assessment and Training

Abstract

Signs and symptoms of Parkinson’s Disease include a combination of slowness of movement, increased tone, tremor and loss of postural reflexes. Cognitive changes and dementia can also be found in older people suffering from PD. The excessive expenditure of cerebral resources in multitasks can cause cognitive overload resulting in deterioration of functional performance. Previous research has highlighted that the balance of cognitive overload is essential for safe driving; however, this has not yet been researched in relation to people with PD. When exposed to demanding traffic scenarios, PD drivers who have already coupled with mental inflexibility and sluggish reasoning can reach dangerous level of cognitive overload. The present study employed computation of arithmetic sums as secondary task to investigate the effect of cognitive overloading on older PD drivers. Methodology: A pre-post case-control study design was implemented. Convenience sample of 28 mild to moderate stages of PD drivers and 30 age-matched healthy controls were recruited and their motor and cognitive functions were assessed. Participants were then assessed twice using a driving simulator: one with exposure to the secondary task and the other without. Results: When compared with healthy controls, PD drivers scored lower in motor and cognitive psychometric assessments and performed less competently in driving assessments (P<0.001). PD drivers drove more cautiously and took more time to complete all the driving tests when compared with the healthy counterparts (P < 0.001). With the distraction of the secondary task, both the performance of PD drivers and controls declined, but PD drivers to a great extent. The Trail-Making Test-B was found to be valuable in predicting the overall performance of PD drivers.Conclusion: The ability of PD participants was observed to have significant deterioration in driving through T-junctions and roundabouts. PD drivers should avoid multitasks in driving as cognitive overload result from which can compound the problem of indecisiveness of the drivers; leading to inconvenience or dangers to other road users. Training on PD drivers should emphasize on intersection manoeuvre management.