Driving is a cognitively demanding activity commonly affected by brain injury and illness. Accurate driving assessment is essential for reducing risk, optimizing independence, and informing driving-related interventions. Virtual reality driving simulation (VRDS) enables safe, sensitive, objective, and standardized measurement of driving abilities. VRDS has been validated in relation to self-reports and driver records. However, self-reports are subjective, and driver records include only major events (collisions, violations). Video telematics platforms can measure naturalistic driving in a more objective and sensitive manner. The present study used video telematics to examine relationships between VRDS performance and directly observed naturalistic driving.

20 healthy adult drivers (ages 23-61, mean age=36; 75% women) completed a VRDS assessment that included 1) driving on a straight road, 2) following a truck on a highway, and 3) reacting to a child running into a street to retrieve a ball. Primary VRDS measures were 1) speed and lane management on the straight road; 2) speed and following distance management in the truck-following task; and 3) reaction time, stopping, and distance from the child in the child-ball task. Participants also completed 28 days of naturalistic driving with a video telematics platform in their vehicle. Driving events were detected automatically using accelerometer, GPS, and video data, and driving behaviors were coded by driving risk analysts. The primary naturalistic measure was the number of unsafe driving behaviors per hour driven; specific driving behaviors served as exploratory variables. We examined correlations between VRDS and naturalistic driving variables. Given limited statistical power, we reported correlations that were small-to-medium or greater (r>.2) in primary analyses and medium-to-large or greater (r>.4) in exploratory analyses.

On average, drivers exhibited approximately one unsafe driving behavior per hour (M=0.9, SD=0.9, range=0.1-2.7). Common behaviors were failing to stop, unsafe following distance, speeding, and cell phone use. No collisions occurred. Average lane position in VRDS (specifically, leftward deviation from the center of the lane) was correlated with more real-world unsafe driving behaviors per hour (r=.35, p=.13), as were higher average straight road speed (r=.26, p=.27), greater straight road speed variability (r=.28, p=.24), and failing to stop for the child in the child-ball task (r=.22, p=.36). In exploratory analyses, failing to stop for the child was associated with real-world distracted driving (r=.45, p=.047), greater lane position variability in VRDS was associated with real-world unsafe following distance (r=.57, p=.009), and greater speed variability in VRDS was associated with real-world seat belt non-use/misuse (r=.49, p=.03).

The present findings provide preliminary evidence that VRDS variables are related to directly observed naturalistic driving, supporting the potential utility of VRDS as a sensitive, ecologically valid driving evaluation tool. As the present study used a small sample of healthy drivers, further research will explore this topic in larger samples and in clinical populations, such as acquired brain injury. Future work will also investigate whether incorporating VRDS with conventional driving evaluation tools (e.g., neuropsychological tests, behind-the-wheel assessments) can enhance the ability of clinical driving evaluations to predict real-world risky driving.

Return to driving after moderate-to-severe traumatic brain injury (TBI) is often a key step in recovery to regain independence. Survivors are often eager to resume driving and may do so despite having residual cognitive limitations from their injury. A better understanding is needed of how cognition and self-awareness impact survivors’ driving after injury. This study examined the influence of cognition and self-awareness on driving patterns following moderate-to-severe TBI.

Participants were 350 adults aged 19-87 years (mean age = 46 years; 70% male) with history of moderate-to-severe TBI, who resumed driving and were enrolled in the TBI Model System. Cross-sectional data were obtained ranging 1-30 years post injury, including questions on driving practices, the Brief Test of Adult Cognition by Telephone (BTACT), and the Functional Independence Measure (FIM). Self-awareness of cognitive function was measured via the discrepancy between dichotomized ratings (intact versus impaired) of objective cognitive testing (BTACT) and self-reported cognitive function (FIM Cognition subscale). Driving patterns included frequency (driving 'more than once a week’ versus 'once a week or less') and restricted driving behavior (total number of driving situations the survivor described as restricted, ranging 0-15). Regression analyses were conducted to examine the relationships between cognition, self-awareness, and each driving outcome (frequency and restriction), followed by causal mediation analyses to examine the mediating effect of self-awareness. Demographics (age, sex, education), injury characteristics (time since injury, injury severity, history of seizures in past year), and medical/social factors (family income, motor function, urban-rural classification) were included in the models as covariates.

Thirty-nine percent of survivors had impaired self-awareness, 88% of survivors drove numerous times per week, and the average survivor reported limited driving in 6 situations (out of 15 total situations). Cognition was inversely related to impaired self-awareness (OR = 0.03, p < 0.001) and inversely related to restricted driving behavior (b = -0.79, p < 0.001). Motor function was positively related to impaired self-awareness (OR = 1.28, p < 0.01). Cognition was not related to driving frequency, and self-awareness did not mediate the relationships between cognition and driving patterns (all p > 0.05).

Most survivors who drive after their injury are driving frequently, but the situations they drive in differ based on their cognitive ability. Impaired self-awareness of cognitive deficits is common after TBI, and self-awareness of cognitive function does not affect driving patterns. Future research needs to focus on how cognition affects nuanced aspects of driving behavior after injury (i.e., types of situations survivors drive in).

Explore the relationship between a motor programming and sequencing procedure and informant rating of patients' functional abilities, especially driving. The Fist-Edge-Palm (FEP; Luria, 1970; 1980) task has previously demonstrated merit distinguishing between healthy controls and those with neurodegenerative processes (Weiner et al., 2011). However, associations between FEP performance and informant-rated functional status, particularly driving ability, have been minimally reported. This exploratory review examined the relationship between FEP, informant-rated driving ability, overall functional impairment, and neurocognitive diagnostic severity.

41 Veterans seen in a South-Central VA Memory Clinic between 08/2020 and 07/2022 served as participants. Neuropsychological assessment included gathering demographic information, chairside neurobehavioral examination (including FEP), cognitive testing, and collateral informant completed Functional Activities Questionnaire (FAQ). Diagnostic severity [no diagnosis, mild cognitive impairment (MCI), dementia (MNCD)] was determined based on the patient's cognitive and functional deficits as measured by neuropsychological testing and informant-rated functional deficits. Correlational analyses were conducted to examine the strength of possible relationships between FEP performance, diagnostic severity, informant-rated functional status including driving impairment. Linear regression analyses determined the extent to which diagnostic severity and FEP performance predict informant-reported driving and ADL impairments

Participants were 97.5% male, 78% white, 22% black. Diagnostically, 3 patients received no diagnoses, 14 with MCI, and 24 with MNCD. Spearman rank correlations were computed; FEP performance was moderately negatively correlated with diagnostic severity [rho = -.35; p < .05] and driving impairment [rho = -.31; p < .05]. Diagnostic severity was moderately positively correlated with driving [rho= .44; p < .05] and total functional [rho = .65; p < .05] impairment. Total functional impairment positively correlated with reported driving impairment [rho = .58; p < .05]. Simple linear regressions tested if FEP performance and diagnostic severity independently predicted informant-reported driving and functional impairment. FEP performance predicted diagnostic severity (R2 = .12, p < .05) and reported driving impairment severity (R2 = .10, p <.05) but did not predict total functional impairment severity (R2 = .06, p = .14). Diagnostic severity predicted both informant-reported driving impairment severity (R2 = .16, p <.05) and functional severity (R2 = .30, p < .05). Multiple regression tested if diagnostic severity and FEP performance together was more predictive of driving and functional impairment than individually; the overall model was predictive of driving (R2 = .19, p < .05) and total functional (R2 = .30, p < .05) impairment, but only diagnostic severity significantly predicted reported driving (B = .63, p < .05) and functional (B = 6.25, p < .05) impairments.

FEP performance was associated with diagnosis and collateral informant concerns of patient driving ability but not statistically related to overall functional impairment or nondriving related ADLs. FEP demonstrates utility in identification of patients demonstrating concerning driving fitness per collateral informants and diagnostic severity due to rapidity of administration, ease of instructing providers, and implementation in a wide variety of clinical settings when a caregiver or informant may not be available. Future directions include explaining the relationship between FEP and driving ability and exploring associations between FEP and other neuropsychological instruments.

Cognitive, motor and sensory deficits associated with aging, and with some neurological conditions such as acquired brain injury, may lead to severe driving performance impairment. While rehabilitation and driver assistance technologies may improve driving performance, the assessment of the actual fitness-to-drive of these people is challenging. Office-based neuropsychological/physical tests are considered insufficient to understand one’s ability to drive. The gold standard is the on-road assessment with dual control cars, superior in ecological validity, but expensive, stressful, and potentially unsafe. Valid, more cost-effective solutions for a safer, more accurate, standardized assessment of fitness-to-drive are currently needed. Modern and sensorized driving simulators offer key advantages, such as the possibility of exposing drivers to several relevant driving scenarios, including hazard situations, and of assessing their driving performance without being physically at risk. However, the extraction and direct interpretation of existing simulator-produced data may require specialized data processing skills or simulation expertise. To overcome this, we have developed an easy-to-use, pencil-and-paper observational instrument. The Sim-DOS is an adaptation of the widely used instrument to assess “natural driving”, the Driving Observation Schedule (DOS; Vlahodimitrakou et al., 2013).

Via expert consensus, DOS targeted behaviors were adapted to a simulated-based environment (signaling, observation of environment, speed regulation, slow or unsafe reaction, distance interpretation, vehicle/lane positioning), and the Sim-DOS scores calculation (based on errors while doing such behaviors) was adapted from DOS to include hazard situations (HS, 0-100) and free driving (FD, 0-°°) scores. The instrument was then piloted with a sample of 35 older adults, along with the collection of simulator-produced data on number of harsh events and driving speed. Participants drove two consecutive 20-minutes long scenarios, with low and high traffic density (LTD, HTD). In each scenario, there were periods with and without potentially hazard situations.

Assessments were performed by two independent trained observers, producing substantial inter-rater reliability (intra-class correlation coefficients above 0.94). Participants (70.7±4.1 years old, 60% male, 46.1±6.7 years of driving experience) were mostly regular drivers (74%). However, psychomotor skills of the majority were compromised, with only one participant being above the 80th percentile in the reaction times test of the national mandatory driving assessment. When exposed to hazard situations, most of the participants (94.1%) did not perform well, independently of traffic density, with average Sim-DOS-HS scores of 87.1±9.7 (out of 100, t-values>7.3, p-values<.05).

Compared to LTD scenarios, in HTD scenarios participants drove less smoothly (HTD:0.97±1.24 vs. LTD:0.33±0.58 of harsh events, Z=3.1, p<.05). However, they also drove slower (HTD:82.41±27.43 vs. LTD:103.55±14.61 km/h, t=5.2, p<.05), improving their ability to manage hazard situations, and therefore producing higher than expected Sim-DOS scores (HTD:87.05±10.28). During free driving, participants performed worse under LTD conditions (Sim-DOS-FD scores: HTD:11.68±6.20 vs. LTD:14.40±9.58, t=2.15, p<.05) as they drove at higher speed (HTD:85.01±24.28 vs. LTD:104.70±11.94 km/h, t=5.8, p<.05), although they did it more smoothly (HTD:1.94±3.74 vs. LTD:0.45±0.74 harsh events, Z=2.65, p<.05).

Our study provides a validated driving assessment tool for use in driving simulators that will allow a safer, more ecologic, holistic and informative evaluation of the fitness-to-drive of older adults and neurological patients.

Daily driving behavior is ultimate measure of cognitive functioning requiring multiple cognitive domains working synergistically to complete this complex instrumental activity of daily living. As the world’s population continues to grow and age older, motor vehicle crashes become more frequent. Cognitive and brain reserve are developing constructs that are frequently assessed in aging research. Cognitive reserve preserves functioning in the face of greater loss of brain structure as experienced during cognitive impairment or dementia. This study determined whether cognitive reserve and brain reserve predict changes in adverse driving behaviors in cognitively normal older adults.

Cognitively normal participants (Clinical Dementia Rating 0) were enrolled from longitudinal studies at the Knight Alzheimer’s Disease Research Center at Washington University. Participants (n=186) were ≥ 65 years of age, required to have Magnetic Resonance Imaging (MRI) data, neuropsychological testing data, as well as one full year of naturalistic driving data prior to the beginning of COVID-19 lockdown in the United States (March 2020). Naturalistic driving behavior data was collected via the Driving Real World In-vehicle Evaluation System (DRIVES). DRIVES variables included idle time, over speeding, aggression, number of trips, including those at day and night. MRI was performed on 3T Tesla using a research imaging protocol based upon ADNI that includes a high-resolution T1 MPRAGE for assessment of brain structures to produce normalized whole brain volume (WBV) and hippocampal volume (HV). WBV and HV were each assessed using tertiles comparing the top 66% with the bottom 33% where the bottom represented increased atrophy. The Word Reading subtest of the Wide Range Achievement Test 4 (WRAT 4) was utilized as a proxy for cognitive reserve. WRAT 4 scores were compared with the top 66% and the bottom 33% where the bottom were poor performers. Linear-mixed-effect models adjusted for age, education, and sex.

Participants on average were older (73.7±4.9), college educated (16.6±2.2), and similar sex distribution (males=100, females=86). Analyses showed statistically significant differences in slopes where participants with increased hippocampal and whole brain atrophy were less likely to overspeed (p=0.0035; p=0.0003), drive aggressively (p=0.0016; p<0.0001), and drive during the daytime (p<0.0001; p<0.0001). However, they were more likely to spend more time idling (p=0.0005; p<0.0001) and drive during the nighttime (p=0.003; p=0.0002). Similar findings occurred with the WRAT 4 where participants with lower scores were less likely to overspeed (p=0.0035), drive aggressively (p=0.0024), hard brake (p=0.0180), and drive during the daytime (p<0.0001) while they were more likely to also spend more time idling (p=0.0012) and drive during the nighttime (p=0.0004).

Numerous changes in driving behaviors over time were predicted by increased hippocampal and whole brain atrophy as well as lower cognitive reserve scores proxied by the WRAT 4. These changes show that those with lower brain and cognitive reserve are more likely to restrict their driving behavior and adapt their daily behaviors as they age. These results suggest older adults with lower brain and cognitive reserve are more likely to avoid highways where speeding and aggressive maneuvers are more frequent.

Although some animal research suggests possible sex differences in response to THC exposure (e.g., Cooper & Craft, 2018), there are limited human studies. One study found that among individuals rarely using cannabis, when given similar amounts of oral and vaporized THC females report greater subjective intoxication compared to males (Sholler et al., 2020). However, in a study of daily users, females reported indistinguishable levels of intoxication compared to males after smoking similar amounts (Cooper & Haney, 2014), while males and females using 1–4x/week showed similar levels of intoxication, despite females having lower blood THC and metabolite concentrations (Matheson et al., 2020). It is important to elucidate sex differences in biological indicators of cannabis intoxication given potential driving/workplace implications as states increasingly legalize use. The current study examined if when closely matching males and females on cannabis use variables there are predictable sex differences in residual whole blood THC and metabolite concentrations, and THC/metabolites, subjective appraisals of intoxication, and driving performance following acute cannabis consumption.

The current study was part of a randomized clinical trial (Marcotte et al., 2022). Participants smoked ad libitum THC cigarettes and then completed driving simulations, blood draws, and subjective measures of intoxication. The main outcomes were the change in Composite Drive Score (CDS; global measure of driving performance) from baseline, whole blood THC, 11-OH-THC, and THC-COOH levels (ng/mL), and subjective ratings of how “high” participants felt (0 = not at all, 100 = extremely). For this analysis of participants receiving active THC, males were matched to females on 1) estimated THC exposure (g) in the last 6 months (24M, 24F) or 2) whole blood THC concentrations immediately post-smoking (23M, 23F).

When matched on THC exposure in the past 6 months (overall mean of 46 grams; p = .99), there were no sex differences in any cannabinoid/metabolite concentrations at baseline (all p > .83) or after cannabis administration (all p > .72). Nor were there differences in the change in CDS from pre-to-post-smoking (p = .26) or subjective “highness” ratings (p = .53). When matched on whole blood THC concentrations immediately after smoking (mean of 34 ng/mL for both sexes, p = .99), no differences were found in CDS change from pre-to-post smoking (p = .81), THC metabolite concentrations (all p > .25), or subjective “highness” ratings (p = .56). For both analyses, males and females did not differ in BMI (both p > .7).

When male/female cannabis users are well-matched on use history, we find no significant differences in cannabinoid concentrations following a mean of 5 days of abstinence, suggesting that there are no clear biological differences in carryover residual effects. We also find no significant sex differences following ad libitum smoking in driving performance, subjective ratings of “highness,” nor whole blood THC and metabolite concentrations, indicating that there are no biological differences in acute response to THC. This improves upon previous research by closely matching participants over a wider range of use intensity variables, although the small sample size precludes definitive conclusions.

Despite three decades of research, gaps remain in meeting the needs of people with dementia and their family/friend carers as they navigate the often-tumultuous process of driving cessation. This paper describes the process of using a knowledge-to-action (KTA) approach to develop an educational web-based resource (i.e. toolkit), called the Driving and Dementia Roadmap (DDR), aimed at addressing some of these gaps.

Aligned with the KTA framework, knowledge creation and action cycle activities informed the development of the DDR. These activities included systematic reviews; meta-synthesis of qualitative studies; interviews and focus groups with key stakeholders; development of a Driving and Dementia Intervention Framework (DD-IF); and a review and curation of publicly available resources and tools. An Advisory Group comprised of people with dementia and family carers provided ongoing feedback on the DDR’s content and design.

The DDR is a multi-component online toolkit that contains separate portals for current and former drivers with dementia and their family/friend carers. Based on the DD-IF, various topics of driving cessation are presented to accommodate users’ diverse stages and needs in their experiences of decision-making and transitioning to non-driving.

Guided by the KTA framework that involved a systematic and iterative process of knowledge creation and translation, the resulting person-centered, individualized and flexible DDR can bring much-needed support to help people with dementia and their families maintain their mobility, community access, and social and emotional wellbeing during and post-driving cessation.

Driving and stopping driving present challenging issues for older people living with memory problems and the family members supporting them. Changes to driving status impact the individual stopping driving and their family members. CarFreeMe is an existing, effective driving cessation program for older people that may be applicable to older people living with dementia. The purpose of this study was to adapt the program and explore feasibility and key stakeholder perspectives.

The Medical Research Council guidelines for conducting research into complex interventions guided the development, acceptability and feasibility piloting. A multidisciplinary approach was taken, and key stakeholders were involved throughout the process. This included an adaptation process, followed by expert reference group feedback and case series pilot study.

The background research indicated that some key changes were required to meet the needs of people living with dementia. Aspects of the content, language, format and activities were adapted and an additional module was created for family members – whose involvement was identified as important. A more personalized, flexible approach was recommended. The expert reference group [psychologists (n = 2), occupational therapists (n = 3) and dementia behavior consultants (n = 2)] indicated the program was appropriate and needed, and made recommendations for feasibility. Pilot testing with three families indicated acceptability.

A driving cessation program adapted for use with people living with dementia and their families required some changes to meet the needs and situations based on feedback from key stakeholders. Future studies will evaluate implementation outcomes across a range of settings.

To investigate effects of a 12-week treatment with atomoxetine (ATX) on driving performance in real traffic, driving-related neuropsychological performance tests and self-evaluation of driving in adult patients with ADHD compared to an untreated control group with ADHD.

Parallel group design with an ATX and a waiting list group. At baseline and endpoint patients were evaluated with a standardized on-road driving test (SDBO), a driving-related neuropsychological test battery (Act and React Test System [ART2020]), and subjective measures of driving performance (one-week driving diary, Driver Coping Questionnaire).

Forty-three of the 64 included patients completed the study (n = 22 ATX, n = 21 controls). Mean intervention period was 11.9 ± 3.0 weeks, mean daily ATX dosage was 71.6 ± 14.9 mg. At endpoint, 60.1% of patients treated with ATX and 0% of waiting list group had reduced ADHD symptoms by greater or equal to 30%. In SDBO, ATX group reduced driving errors in three of four driving performance categories (attention, P < 0.05; risk-related self-control, P < 0.005; driver skills, P < 0.001), number of driving errors remained stable in control group. At endpoint, 47.6% of control group and 18.2% of ATX group (P < 0.05) did not fulfil the driving fitness criteria according to German Guidelines (percentile rank less or equal to 16 in one or more subtests in ART2020). Total number of self-reported critical traffic situations decreased from 12.0 to 6.8 per week in ATX group (P < 0.05) and remained stable in controls by 9.3 and 9.9 at baseline and endpoint (ns). Coping strategies with stressful traffic situations did not change within both groups.

Our study provides first evidence that treatment with ATX improves driving performance in real traffic in adults with ADHD.