Cognitive functioning differentially predicts different dimensions of older drivers’ on-road safety

Abstract

The extent to which deficits in specific cognitive domains contribute to older drivers’ safety risk in complex real-world driving tasks is not well understood. We selected 148 drivers older than 70 years of age both with and without neurodegenerative diseases (Alzheimer disease-AD and Parkinson disease-PD) from an existing driving database of older adults. Participant assessments included on-road driving safety and cognitive functioning in visuospatial construction, speed of processing, memory, and executive functioning. The standardized on-road drive test was designed to examine multiple facets of older driver safety including navigation performance (e.g. following a route, identifying landmarks), safety errors while concurrently performing secondary navigation tasks (“on-task” safety errors), and safety errors in the absence of any secondary navigation tasks (“baseline” safety errors). The inter-correlations of these outcome measures were fair to moderate supporting their distinctiveness. Participants with diseases performed worse than the healthy aging group on all driving measures, and differences between those with AD and PD were minimal. In multivariate analyses, different domains of cognitive functioning predicted distinct facets of driver safety on road. Memory and set-shifting predicted performance in navigation-related secondary tasks, speed of processing predicted on-task safety errors, and visuospatial construction predicted baseline safety errors. These findings support broad assessments of cognitive functioning to inform decisions regarding older driver safety on the road and suggest navigation performance may be useful in evaluating older driver fitness and restrictions in licensing.

The relations between specific measures of simulated driving ability and functional ability: New insights for assessment and training programs of older drivers

“…Recent research has provided positive evidence for simulator validity Fisher et al, 2011;Shechtman, Classen, Awadzi, & Mann, 2009), nevertheless a validation on road is necessary to validate our conclusions that each specific driving measure is related to a specific set of functional abilities and that only a small proportion of the variability observed in specific driving measures is explained by functional abilities. Results of recent studies investigating the relation between cognitive abilities and driving errors in different situations on road seems to be in line with our results (Aksan et al, 2015;Anstey & Wood, 2011). However, future research should investigate the relation between several measures of driving ability on road (not only driving errors) with several functional abilities (not only cognitive abilities) since the results of the present study indicate that each specific driving measure is related to a specific set of functional abilities.…”

“…This latter driving measure was also predicted by visual acuity. This finding, that it depends on the specific driving measure under investigation, is in line with previous studies with older drivers specifically addressing this issue (Aksan et al, 2015;Anstey & Wood, 2011;Mullen et al, 2008). For example, the UFOV predicted performance on a rural highway course, while the ANT also predicted performance on parking lot courses (Mullen et al, 2008).…”

“…Although some studies investigating the relations between specific measures of older drivers' driving and functional ability were already conducted (Aksan, Anderson, Dawson, Uc, & Rizzo, 2015;Anstey & Wood, 2011;Backs, Tuttle, Conley, & Cassavaugh, 2011;Jongen et al, 2012;Mullen et al, 2008;Shanmugaratnam, Kass, & Arruda, 2010;Szlyk, Myers, Zhang, Wetzel, & Shapiro, 2002;Tuttle, Cassavaugh, & Backs, 2009), these mainly focused on measures of cognitive ability. Here, in addition to measures of cognitive ability, measures of visual and motor ability were included.…”

The effects of cognitively demanding dual-task driving condition on elderly people’s driving performance; Real driving monitoring

“…Previous studies show that older drivers (+75) have the highest crash rate among all the age groups (Eby et al, 1998). In addition, cognitive impairments which are likely to appear in age over 65 decline the driving safety (Aksan et al, 2015). However, the patterns of accidents vary among different groups of older people.…”

Road safety in an aging population: risk factors, assessment, interventions, and future directions

“…Generic tools and dementia screening instruments do not assess the specific deficits that cause drivers to become unsafe. A consistent body of research has demonstrated that memory deficits are not typically associated with unsafe driving (Reger et al, 2004;Anstey et al, 2005;Aksan et al, 2015), which may explain why patients with early AD may continue to drive safely. In contrast, deficits in executive function, visual selective attention, and processing speed predict crashes in older drivers (Ball et al, 2006;Dawson et al, 2010;Anstey et al, 2012).…”