Maud Ranchet

Impact of specific executive functions on driving performance in people with Parkinson's disease

Executive functions encompass various cognitive processes and are critical in novel or demanding driving situations. Our aim was to determine the role of impairments in specific executive functions (updating, flexibility, inhibition) on road performance in drivers with Parkinsons disease (PD), a condition commonly associated with early executive dysfunction. In this pilot study, 19 patients with mild to moderate PD and 21 healthy controls matched for age, education, and driving experience were tested using a neuropsychological battery assessing global cognitive abilities, updating (n‐back task), flexibility (plus‐minus task), and inhibition (Stroop test). Participants also underwent a 45‐minute road test in which they were scored by a driving instructor and a second experimenter. To separate “at‐risk” drivers from safe drivers, a composite driving indicator was calculated from the Test Ride for Investigating Practical Fitness to Drive score, the penalty score from the observation grid, and the number of safety interventions made by the driving instructor. Eight of the 40 drivers (all PD) were rated as “at risk.” Measures of updating (the n‐back task) and mental flexibility (the plus‐minus task) predicted driving safety even after adjustment for group status, explaining 53% of the total variance. These 2 tests also discriminated between safe and “at‐risk” drivers within the PD group. These findings, although preliminary, suggest that updating and mental flexibility are critical for safe driving in PD. Assessment batteries for driving fitness should probe different aspects of executive functions, specifically when evaluating drivers with PD.

Relationships between Cognitive Functions and Driving Behavior in Parkinson’s Disease

Alterations in cognitive functions in Parkinson’s disease (PD) have been reported even in mild stages of the disease. These functions may play a role in complex daily activities, such as driving. This article provides an overview on the relationships between cognitive functions and driving behavior in PD in driving simulator and on-road studies. The role of attention, executive functions, visual memory, visuospatial construction and information processing speed is discussed. In driving simulator studies, driving performances were correlated with several neuropsychological measures, especially those of Trail Making Test (TMT), Brixton and Symbol Digit Modalities Test. In on-road studies, TMT, Useful Field Of View and Block Design tests appear as good predictors of driving performances. Most of these tests are also relevant to driving in Alzheimer’s disease and traumatic brain injury.

Establishing an evidence-base framework for driving rehabilitation in Parkinson's disease: a systematic review of on-road driving studies

BACKGROUND Individuals with Parkinsons disease (PD) experience problems with on-road driving that can be targeted in driving rehabilitation programs. OBJECTIVE To provide a framework for driving rehabilitation in PD by identifying the critical on-road driving impairments and their associated visual, cognitive, and motor deficits. METHODS We conducted a systematic review of the literature on on-road driving and naturalistic driving practices in PD. Relevant databases including Pubmed, Medline, PsychINFO, ISI Web of Science, Cochrane library, and ClinicalTrials.gov, were reviewed using the key words Parkinsons disease, on-road driving, naturalistic driving, and their related entry words. On-road driving skills were mapped onto an existing theoretic model of operational, tactical, and strategic levels. The on-road and off-road cognitive, motor, and visual predictors of global on-road driving were summarized. RESULTS Twenty-seven studies were included. All but one study were prospective and Class II studies according to the American Academy of Neurology Classification Criteria. Participants were on average 68 years old and in the mild to moderate stages of PD. Drivers with PD were more likely to fail a driving assessment compared to age- and gender-matched controls. Compared with controls, drivers with PD experienced difficulties on all levels of driving skill. However, the compensation strategies on the strategic level showed that drivers with PD were aware of their diminished driving skills on the operational and strategic levels. Operational and tactical on-road driving skills best predicted global on-road driving. A combination of visual, cognitive, and motor deficits underlie impaired on-road driving performance in PD. CONCLUSION Driving rehabilitation strategies for individuals with PD should include training of operational and tactical driving skills or indirect comprehensive training program of visual, cognitive, and motor skills.

Agreement between physician's recommendation and fitness-to-drive decision in multiple sclerosis

OBJECTIVE To investigate the agreement of fitness-to-drive decisions made by the referring physicians and by the on-road assessors in individuals with multiple sclerosis (MS). DESIGN Retrospective analysis. SETTING Driving institute. PARTICIPANTS A sample of individuals with MS (N=218) who completed the medical and driving questionnaire and performed an official on-road test. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURE Fitness-to-drive decision made by the on-road assessor. RESULTS The referring physician and on-road assessor agreed on fitness to drive in 191 (88%) of the cases (prevalence-adjusted and bias-adjusted κ=.81, P<.0001). When compared with the on-road assessors judgment, the physicians recommendation of fitness to drive was overestimated in 16 individuals with MS and underestimated in 11 individuals with MS. Patients with poor binocular acuity were more likely to be inaccurately classified by the physician (P=.001). CONCLUSIONS This study showed a high level of agreement between the fitness-to-drive decisions made by the physicians and the on-road assessors in individuals with MS. Visual functions should be assessed in the doctors office for more accurate referrals.

Fitness-to-drive agreements after stroke: medical versus practical recommendations

Physicians often struggle to screen out patients who are no longer fit to drive after stroke. The agreement between the recommendations of physicians and on‐road assessors with regard to fitness to drive after stroke was investigated.

Emulation of Physician Tasks in Eye-Tracked Virtual Reality for Remote Diagnosis of Neurodegenerative Disease

For neurodegenerative conditions like Parkinsons disease, early and accurate diagnosis is still a difficult task. Evaluations can be time consuming, patients must often travel to metropolitan areas or different cities to see experts, and misdiagnosis can result in improper treatment. To date, only a handful of assistive or remote methods exist to help physicians evaluate patients with suspected neurological disease in a convenient and consistent way. In this paper, we present a low-cost VR interface designed to support evaluation and diagnosis of neurodegenerative disease and test its use in a clinical setting. Using a commercially available VR display with an infrared camera integrated into the lens, we have constructed a 3D virtual environment designed to emulate common tasks used to evaluate patients, such as fixating on a point, conducting smooth pursuit of an object, or executing saccades. These virtual tasks are designed to elicit eye movements commonly associated with neurodegenerative disease, such as abnormal saccades, square wave jerks, and ocular tremor. Next, we conducted experiments with 9 patients with a diagnosis of Parkinsons disease and 7 healthy controls to test the systems potential to emulate tasks for clinical diagnosis. We then applied eye tracking algorithms and image enhancement to the eye recordings taken during the experiment and conducted a short follow-up study with two physicians for evaluation. Results showed that our VR interface was able to elicit five common types of movements usable for evaluation, physicians were able to confirm three out of four abnormalities, and visualizations were rated as potentially useful for diagnosis.

Comorbidity in Drivers with Parkinson's Disease

To determine the effect of comorbidity on fitness‐to‐drive recommendations that physicians and on‐road driving assessors make and to investigate the agreement in fitness‐to‐drive recommendations between physicians and on‐road driving assessors.

Fitness-to-drive Disagreements in Individuals With Dementia

Purpose of the Study We sought to investigate the agreement between medical and practical fitness-to-drive recommendations in active drivers with dementia. Design and Methods In this retrospective study, 68 patients underwent medical, visual, and road tests at an official center of the Belgian Road Safety Institute. Physicians provided medical fitness-to-drive recommendations using 1 of 3 categories (favorable, reserved, or unfavorable). On-road assessors used the same 3 categories to make practical fitness-to-drive recommendations. Agreement between the medical and practical fitness-to-drive recommendations was calculated using the percentage of agreement (p0) and weighted kappa (kw). Results Low agreement was found between physicians and on-road assessors regarding their fitness-to-drive recommendations (p0 = 43%, kw = 0.11, p = .20). Compared with the on-road assessors, the physicians overestimated the fitness to drive of 24 (35%) patients and underestimated the fitness to drive of 15 (22%) patients. Patients who incurred more traffic violations were more likely to be overestimated than underestimated by the physician (p = .03). Implications This study showed disagreements between the fitness-to-drive recommendations made by the physicians and the on-road assessors in more than half of drivers with dementia. Efforts need to be made to improve the communication between physicians and on-road assessors for joint decision making of fitness to drive in dementia.

Cognitive workload across the spectrum of cognitive impairments: A systematic review of physiological measures

HIGHLIGHTSCognitive workload is defined as the mental effort required to execute a task.Greater cognitive workload was found in healthy older adults compared to younger adults.The same was observed in patients with mild cognitive impairment compared to healthy older adults.Behavioral performance declined when cognitive resources available became insufficient.Potential of physiological measures in early detection of cognitive deficits. ABSTRACT Our objective was to identify the physiological measures that are sensitive to assessing cognitive workload across the spectrum of cognitive impairments. Three database searches were conducted: PubMed, PsychINFO, and Web of Science. Studies from the last decade that used physiological measures of cognitive workload in older adults (mean age >65 years‐old) were reviewed. The cognitive workload of healthy older individuals was compared with the cognitive workload of younger adults, patients with mild cognitive impairment (MCI), and patients with Alzheimers diseases (AD). The most common measures of cognitive workload included: electroencephalography, magnetoencephalography, functional magnetic resonance imaging, pupillometry, and heart rate variability. These physiological measures consistently showed greater cognitive workload in healthy older adults compared to younger adults when performing the same task. The same was observed in patients with MCI compared to healthy older adults. Behavioral performance declined when the available cognitive resources became insufficient to cope with the cognitive demands of a task, such as in AD. These findings may have implications for clinical practice and future cognitive interventions.

Driving after Concussion: Is It Safe To Drive after Symptoms Resolve?

Post-concussion impairments may result in unsafe driving performance, but little research is available to guide consensus on when concussed individuals should return to driving. The purpose of this study was to compare driving performance between individuals with and without a concussion and to explore relationships between neuropsychological and driving performance. Fourteen participants with concussion (age 20.2 ± 0.9 years old) and 14 non-concussed age- and driving experience-matched controls (age 20.4 ± 1.1 years old) completed a graded symptom checklist, a brief neuropsychological exam, and a 20.5 km driving simulation task. Participants with a concussion completed driving simulation within 48 h of becoming asymptomatic (15.9 ± 9.0 days post-concussion). One-way analyses of variance were used to compare total number of crashes, tickets, and lane excursions, as well as standard deviation of lateral position (SDLP) and standard deviation of speed. Pearsons correlations were conducted to explore the relationship between the neuropsychological and driving performance separately by group (α = 0.05). Participants with a concussion committed more frequent lane excursions (concussed 10.9 ± 4.5; controls 7.4 ± 2.4; p = 0.017) and exhibited greater SDLP, compared with controls, during the first curve (concussed 45.7 ± 21.3 cm, controls 27.4 ± 6.1 cm; p = 0.030) and final curve (concussed 39.6 ± 24.4 cm; controls 33.5 ± 21.3 cm; p = 0.036). Poorer performance on symbol digit modalities (r = -0.54), Rey Osterrieth Complex Figure (r = -0.53), verbal memory (r = -0.77), and motor speed (r = -0.54) were correlated with more frequent lane excursions in the concussed group, but not in the control group. Despite being asymptomatic, concussed participants exhibited poorer vehicle control, especially when navigating curves. Driving impairments may persist beyond when individuals with a concussion have returned to driving. Our study provides preliminary guidance regarding which neuropsychological functions may best indicate driving impairment following concussion.