Personality traits and executive functions related to on-road driving performance among older drivers

Risk assessment of driver performance in the oil and gas transportation industry: Analyzing the relationship between driver vigilance, attention, reaction time, and safe driving practices

The increasing use of road traffic for land transportation has resulted in numerous road accidents and casualties, including those involving oil and gas tanker vehicles. Despite this, little empirical research has been conducted on the factors influencing tanker drivers' performance. This study aims to address this knowledge gap, particularly in the energy transportation industry, by examining the driving performance factors that affect tanker drivers and incorporating risk assessment measures. The model variables were identified from the literature and used to develop a survey questionnaire for the study. A total of 307 surveys were collected from Malaysian oil and gas tanker drivers, and the driving performance factors were contextually adjusted using the Exploratory Factor Analysis (EFA) approach. The driving performance model was developed using partial least squares structural equation modeling (PLS-SEM). The EFA results categorized driving performance into two constructs: 1) drivers' reaction time with β = 0.320 and 2) attention and vigilance with β value = 0.749. The proposed model provided full insight into how drivers' reaction time, attention, and vigilance impact drivers' performance in this sector, which can help identify potential risks and prevent accidents. The findings are significant in understanding the factors that affect oil and gas drivers' performance and can aid in enhancing oil and gas transportation management by including effective risk assessment measures to prevent fatal crashes.

Digital clock drawing test reflects visuospatial ability of older drivers

Objectives

To keep older drivers safe, it is necessary to assess their fitness to drive. We developed a touch screen-based digital Clock Drawing Test (dCDT) and examined the relationship between the dCDT scores and on-road driving performance of older drivers in a community-setting.

Methods

One hundred and forty-one community-dwelling older drivers (range; 64-88 years old) who participated in this study were included in the analysis. Participants completed the dCDT, the Mini-Mental State Examination-Japanese (MMSE-J), and an on-road driving assessment. We examined the relationship between dCDT scores using the method by Rouleau et al. (maximum 10 points) and the on-road driving performance based on a driving assessment system originally developed by Nagoya University.

Results

Multiple regression analyses showed that errors in the driving test were associated with dCDT score for the items "confirmation," "turning left" and "maintains driving lane position".

Discussion

This study confirmed the relationship between the dCDT score and driving errors, such as confirmation, turning left and maintaining driving lane position. The increase in these errors indicates a decline in visuospatial ability while driving. The dCDT score may reflect older drivers' visuospatial abilities while driving.

Driving Frequency Modulates Correlations Between Executive Functions and Driving Performance: A Driving Simulator Study

Driving a car requires a complex combination of various cognitive functions (e.g., visual perception, motor control, decision making, and others), and deficits in any of these processes may compromise driving safety. Amongst these, executive functions such as inhibitory control, task switching, and decision-making are important, as they enable drivers to process information from their surroundings and respond appropriately to changing road conditions. Although previous research has focused on laboratory measures of individual executive functions, it remains unclear whether performance on such laboratory tests readily translates to actual on-the-road driving performance, especially since drivers' skill levels can vary widely, based on their driving frequency. To this end, we divided 30 participants into two categories based on their driving frequency (i.e., daily commuter vs. weekend only drivers), and we used three well-known executive functioning tasks (the stop signal task, Iowa gambling task or IGT, and a task-switching test) to see whether scores on these tasks predicted such driving performances and behaviors such as braking time, lane-keeping, speed limit violations, and inter-vehicle distance (e.g., in a driving simulator). Participants went through a follow-lead-car scenario in the driving simulator for 20 minutes and then completed the three executive tasks. We found that stop signal reaction time (SSRT) best predicted driving performance, and remained predictive against driver distraction, as well as variabilities in driving frequency. The IGT predicted speed limit violations in high-frequency drivers, whereas task-switching cost predicted lane keeping performance in low-frequency drivers. Together, these results highlight the importance of driving frequency when considering correlates between executive functions and driving performance and behavior. They also imply that executive tasks better predict driving performance in low-frequency (or inexperienced) drivers, while driver temperament (i.e., impulsiveness as indicated by IGT) better predicted driving performance in high-frequency (or experienced) drivers.

Personality Is Associated with Driving Avoidance in the Canadian Longitudinal Study on Aging (CLSA)

As individuals age and become aware of changes in their driving capabilities, they are more likely to self-regulate their driving by avoiding certain driving situations (i.e., night driving, rush hour traffic, etc.). In this paper, we sought to examine the correlates of situational driving avoidance with a particular emphasis on the roles of personality traits, gender, and cognition within a large sample of mid-life and older adults from the Canadian Longitudinal Study on Aging (CLSA). Our findings show that women of older ages tend to report more driving avoidance and that personality traits, specifically extraversion, emotional stability, and openness to experience, may reduce driving avoidance. A negative association was also found between cognition and driving avoidance, such that individuals with higher cognition reported less driving avoidance.

Evaluation of Psychophysical Fitness in Drivers over 65 Years of Age

BACKGROUND

The deterioration of cognitive and psychophysical ability associated with aging has an effect on road safety, especially in the driving of vehicles. The current study's main objective is to evaluate the psychophysical aptitudes in drivers over 65 years of age in a sample of drivers in Spain.

METHODS

The sample was formed of a total of 1663 drivers who attended a Driver Recognition Center. The evaluation of their psychophysical aptitudes was carried out following the Medical-Psychological Exploration Protocol for Driver Recognition Centers, edited by the Ministry of Health and the General Directorate of Traffic.

RESULTS

The results show increased restrictions in the evaluation of driving ability with age, which are especially significant after 75 years of age. Regarding sex, 70.1% of women have an approved evaluation, compared to men aged between 65-69, although from 69 onwards, the percentage of approved women decreases significantly. The loss of visual capabilities and poor performance in psycho-technical tests are the main causes associated with an evaluation with restrictions, with the number of restrictive conditions increasing with age.

CONCLUSIONS

There is an increase in the number of cases with age-related restrictions, especially in the case of women and ophthalmologic-related problems, although the majority of drivers over 65 years old continue driving, thus continuing with a practice that has been related to the well-being and quality of life of older adults.

On the importance of working memory in the driving safety field: A systematic review

In recent years, many studies have used poor cognitive functions to explain risk safety differences among drivers. Working memory is a cognitive function with information storage and attentional control that plays a crucial role in driver information processing. Furthermore, it is inextricably linked to parameters such as driving performance, driving eye movements and driving neurophysiology, which have a significant impact on drivers' risky behavior and crash risk. In particular, crash risk is a serious risk to social safety and economic development. For this reason, it is necessary to understand how risk-related working memory affects driving so that pre-driving safety pre-training programs and in-vehicle safety assistance systems for driving can be developed accordingly, contributing to the development of semi-autonomous vehicles and even autonomous vehicles. In this paper, a systematic search of the literature over the past 23 years resulted in 78 articles that met the eligibility criteria and quality assessment. The results show that higher working memory capacity, as measured neuropsychologically, is associated with more consistent and safer driving-related parameters for drivers (e.g., lane keeping) and may be related to pupil dilation during risk perception while driving, which is associated with driving outcomes (tickets, pull-overs, penalty points and fines,and driving accidents) is closely related to the perceived usefulness of the human-machine interface, reaction time, standard deviation of steering wheel corners, etc. when the autonomous driving takes over. In addition, higher working memory load interference was associated with more inconsistent and unsafe driving-related parameters (including but not limited to eye movements, electrophysiology, etc.), with higher working memory load being associated with easier driver concentration on the road, faster heart rate, lower heart rate variability, and lower oxyhemoglobin (OxyHb) and deoxyhemoglobin (DeoxyHb). Only a limited number of studies have simultaneously investigated the relationship between working memory capacity, working memory load and driving, showing an interaction between working memory capacity and working memory load on lane change initiation and lane change correctness, with working memory capacity acting as a covariate that mediated the effect of working memory load on braking reaction time. In addition, working memory-related cognitive training had a transfer effect on improving driving ability. Overall, working memory capacity determines the upper limit of the number of working memory attention resources, while working memory load occupies part of the working memory attention resources, thus influencing information perception, decision judgment, operational response, and collision avoidance in driving. Future effective interventions for safe driving can be combined with capacity training and load alerting. These findings contribute to our understanding of the role of working memory in driving and provide new insights into the design of driver safety training programs and automated driving personalized in-vehicle safety systems and roadside devices such as signage.

Decline in Other Instrumental Activities of Daily Living as Indicators of Driving Risk in Older Adults at an Academic Memory Clinic

BACKGROUND

Decisions around driving retirement are difficult for older persons living with cognitive decline and their caregivers. In many jurisdictions, physicians are responsible for notifying authorities of driving risks. However, there are no standardized guidelines for this assessment. Having access to a driving risk assessment tool could help older adults and their caregivers prepare for discussions around driving retirement. This study compares the clinical profiles of older adult drivers assessed in an academic memory clinic who were referred to the driving authority to older drivers who were not with a focus on instrumental activities of daily living (iADLs).

METHODS

Data on referred (R) and not-referred (NR) drivers were extracted from medical records. Elements from the medical history, cognitive history, functional abilities, Modified Mini-Mental State (3MS) examination, Trails A/B, and clock drawing were included in the analysis. Four risk factors of interest were examined in separate logistic regression analyses, adjusted for demographic variables.

RESULTS

50 participants were identified in each group. The R group was older on average than the NR. As expected, R were more likely to have Trails B scores over 3 min and have significantly abnormal clock drawing tests. R also showed lower 3MS scores and a higher average number of functional impairments (including managing appointments, medications, bills, or the television).

CONCLUSION

Beyond standard cognitive tests, impairment in iADLs may help general practitioners identify at-risk drivers in the absence of standardized guidelines and tools. This finding can also inform the design of a risk assessment tool for driving and could help with approaches for drivers with otherwise borderline test results.

Trait anger causes risky driving behavior by influencing executive function and hazard cognition

Drivers with a high level of trait anger feel more intensity of anger on road, contributing to more risky driving behavior and further increasing the probability of collisions. It seems that trait anger directly correlates with risky driving behavior, but how it works in detail remains unknown and previous research indicated executive function and hazard cognition may play a mediation role in it. Our research aims to explore the relationship among these variables and test if there is a multiple mediation model. We sampled 302 valid participants and used online questionnaires, containing trait anger scale (TAS), executive function index (EFI), hazard cognition scale (HCS; representing attitudes towards risky driving behavior), driver behavior questionnaire (DBQ), and self-reported traffic violations (e.g., accidents, penalty points, fines). Hierarchical multiple linear regression of DBQ results show trait anger is a medium but statistically significant predictor of risky driving behavior and drivers' attitude towards risky situations can significantly predict risky driving behavior at medium effect. But risky driving behavior cannot be predicted by executive function. Interestingly, opposing to prior research, zero-inflated Poisson regression analysis of self-reported traffic violations suggests trait anger negatively predicts accidents and fines in the zero-inflation model, and hazard cognition negatively predicts penalty points. Notably, the executive function negatively predicts penalty points and fines in the count model, which confirms our hypothetical direction. They all represent a small effect size in this nonlinear regression model. Path analysis suggested that trait anger influences risky driving behavior through executive function, and hazard cognition both separately and jointly. This study provides a theoretical framework for the transaction model of aggressive driving behavior and offers some possible interventions toward the effect of trait anger on risky driving behavior.

Driving-Related Cognitive Abilities: Evaluating Change over Time in a Sample of Older Adults Undergoing an Assessment Regarding Fitness to Drive

Advancing age can bring a decline in many driving-related cognitive abilities. For this reason, public safety concern has raised about older adults' driving performance, and many countries have adopted screening polices to assess older drivers' fitness to drive. As a result of such assessments, authorities may impose behavioral restrictions to driving. The present study examines whether driving-related cognitive abilities change over time and compares drivers either restricted or not by licensing authorities after the first assessment. The data were derived from a database provided by a service of psychodiagnostic assessment of fitness to drive. This database contained data of people referred for cognitive assessment in order to renew their driving license over the period of 2016 to 2022. The sample included 58 cognitively healthy old drivers (mean age = 82.79, SD = 6.13; 97% men) with a follow-up examination (T2) after a period ranging from one to four years (M = 1.59, SD = 0.72) since the first assessment. Cognitive assessments were conducted using the standard test battery from the Vienna Test System (VTS8; ©Schuhfried GmbH, Mödling, Austria). Decision time variability, motor time, reaction time under stress, and obtaining an overview did not show significant changes between T1 and T2, whereas selective attention and inductive reasoning significantly decreased over time in both groups. Improvements in processing speed consistent with practice effects emerged at T2. Restricted drivers (n = 41) maintained significantly worse performances than unrestricted drivers (n = 17) in the follow-up assessment. Chronological age was associated with higher reaction time under stress, while education showed a buffering role against a decrease in perceptual speed. Overall, although older drivers' driving-related cognitive abilities remain relatively stable over the short-term, the decline in some cognitive functions deserves reevaluation and monitoring.

Ecological validity of executive function tests in predicting driving performance

Almost all of our everyday activities depend on executive function (EF) skills. In line with the increasing attention to the ecological validation of neuropsychological assessment and intervention methods, this study aimed to explore the ecological validity of a relevant set of widely used EF tests, mostly from well-known paradigms of EF assessment, in predicting driving ability. Ninety-six healthy novice drivers (Mage = 26.2 years, SD = 8.4; 48 female) completed four stages of our data collection including psychological, EF, and driving assessments. For the psychological assessment, validated measures of sensation-seeking, risk-taking, personality traits, ADHD symptoms, depression, anxiety, and stress were administered. For the EF assessment, selected tests from the Delis-Kaplan Executive Function System (D-KEFS: Trail Making, Design Fluency, and Tower) and the Behavioral Assessment of the Dysexecutive Syndrome (BADS: Key Search, Zoo Map, and Modified Six Elements) along with a computerized Stroop test were administered. For the driving assessment, we used a simulated driving test comprising of 14 key dimensions of driving skills. Several correlations and multiple regression analyses were conducted. Significant correlations were found between all the EF measures and driving performance. Moreover, the EF measures predicted the driving ability over and above the effects of previous driving experience and the psychological variables. These results provide supporting evidence for the ecological validity of the EF tests in predicting driving performance. The incorporation of assessment and intervention targeting multiple domains of EF into driving rehabilitation and education programs could be a focus of future research.

Age-related effects of executive function on takeover performance in automated driving

The development of highly automated vehicles can meet elderly drivers' mobility needs; however, worse driving performance after a takeover request (TOR) is frequently found, especially regarding non-driving related tasks (NDRTs). This study aims to detect the correlation between takeover performance and underlying cognitive factors comprising a set of higher order cognitive processes including executive functions. Thirty-five young and 35 elderly participants were tested by computerized cognitive tasks and simulated driving tasks to evaluate their executive functions and takeover performance. Performance of n-back tasks, Simon tasks, and task switching were used to evaluate updating, inhibition, and shifting components of executive functions by principal component analysis. The performance of lane changing after TOR was measured using the standard deviation of the steering wheel angle and minimum time-to-collision (TTC). Differences between age groups and NDRT engagement were assessed by two-way mixed analysis of variance. Older participants had significantly lower executive function ability and were less stable and more conservative when engaged in NDRT. Furthermore, a significant correlation between executive function and lateral driving stability was found. These findings highlight the interaction between age-related differences in executive functions and takeover performance; thus, provide implications for designing driver screening tests or human-machine interfaces.

Impact of Age on Takeover Behavior in Automated Driving in Complex Traffic Situations: A Case Study of Beijing, China

Research on the influence of age on various automated driving conditions will contribute to an understanding of driving behavior characteristics and the development of specific automated driving systems. This study aims to analyze the relationship between age and takeover behavior in automated driving, where 16 test conditions were taken into consideration, including two driving tasks, two warning times and four driving scenarios. Forty-two drivers in Beijing, China in 2020 were recruited to participate in a static driving simulator with Level 3 (L3) conditional automation to obtain detailed test information of the recorded takeover time, mean speed and mean lateral offset. An ANOVA test was proposed to examine the significance among different age groups and conditions. The results confirmed that reaction time increased significantly with age and the driving stability of the older group was worse than the young and middle groups. It was also indicated that the older group could not adapt to complex tasks well when driving due to their limited cognitive driving ability. Additionally, the higher urgency of a scenario explained the variance in the takeover quality. According to the obtained influencing mechanisms, policy implications for the development of vehicle automation, considering the various driving behaviors of drivers, were put forward, so as to correctly identify the high-risk driving conditions in different age groups. For further research, on-road validation will be necessary in order to check for driving simulation-related effects.

The effects of age and physical exercise on multimodal signal responses: Implications for semi-autonomous vehicle takeover requests

The present study examined whether the non-chronological age factor, engagement in physical exercise, affected responses to multimodal (combinations of visual, auditory, and/or tactile) signals differently between younger and older adults in complex environments. Forty-eight younger and older adults were divided into exercise and non-exercise groups, and rode in a simulated Level 3 autonomous vehicle under four different task conditions (baseline, video watching, headway estimation, and video-headway combination), while being asked to respond to various multimodal warning signals. Overall, bi- and trimodal warnings had faster response times for both age groups across driving conditions, but was more pronounced for older adults. Engagement in physical exercise was associated with smaller maximum braking force for younger participants only, and also corresponded to longer average fixation durations, compared to the non-exercise group. Findings from this research can help to guide decisions about the design of warning and information systems for semi-autonomous vehicles.

Impact of Safety Culture Implementation on Driving Performance among Oil and Gas Tanker Drivers: A Partial Least Squares Structural Equation Modelling (PLS-SEM) Approach

This research aims to develop a safety culture model by investigating the relationship between safety culture and driving performance. In previous studies, safety culture has been one of the factors that determine safety issues. These issues were then contextually transformed via a pilot study and organized in the form of a theoretical model. The data were collected from 307 oil and gas tanker drivers in Malaysia through questionnaire surveys. Consequently, structural equation models of partial least squares (PLS-SEM) were applied to statistically assess the final model of this study. The results showed that the implementation of safety culture contributes to driving performance at a substantial level; there is a strong association with an effect of 67.3%. The findings of this research would serve as a benchmark for decision-makers in the oil and gas transportation sector, as promoting an awareness of safety culture should boost the efficiency of drivers. This research fills a gap in knowledge by identifying that positive safety culture practices and mindset are direct antecedents for the improvement of driver performance and, thus, the avoidance of road accidents.

The Impact of Two MMPI-2-Based Models of Personality in Predicting Driving Behavior. Can Demographic Variables Be Disregarded?

The driver’s personality is a key human factor for the assessment of the fitness to drive (FTD), affecting driving decisions and behavior, with consequences on driving safety. No previous study has investigated the effectiveness of Minnesota Multiphasic Personality Inventory (MMPI)-2 scales for predicting the FTD. The present study aimed to compare two MMPI-2-based models of normal and pathological personality traits (i.e., Inventory of Driving-related Personality Traits (IVPE)-MMPI vs. Personality Psychopathology Five (PSY-5) scale) in predicting the cognitive FTD. One hundred young and eighty-seven adult active drivers completed the MMPI-2 questionnaire as a measure of personality and a computerized driving task measuring for resilience of attention (Determination Test (DT)), reaction speed (Reaction Test (RS)), motor speed (MS), and perceptual speed (Adaptive Tachistoscopic Traffic Perception Test (ATAVT)). The effects of age, gender, and education were also controlled. Results showed that the models controlled for demographics overperformed those neglecting them for each driving outcome. A negative effect of age was found on each driving task; the effect of gender, favoring males, was found in both the RS and the MS, and the effect of education was found on the DT and the ATAVT. Concerning personality traits, significant effects were found of sensation seeking (IVPE-MMPI) on each outcome; of anxiety (as a measure of emotional instability; IVPE-MMPI) and introversion (PSY-5) on the measures of MS; and of psychopathic deviation (as a measure of self-control; IVPEMMPI) on the DT. The study confirmed the key role of demographic factors in influencing the FTD, further suggesting the usefulness of some MMPI2-based personality scales in the assessment of driving-related personality determinants.

Cognitive Reserve and Driving-Related Cognitive Abilities in a Sample of Oldest Old Drivers Undergoing Assessment of Fitness to Drive

This study examines the relationship between age, cognitive reserve (CR), and driving-related cognitive abilities in a sample of oldest old drivers undergoing evaluation of fitness to drive. Structural equation modeling was used to investigate the associations between age, CR, and performances to a standardized set of cognitive tests assessing fitness to drive. Education and work complexity were used as proxy measures of CR. The results showed both measures of CR, but not age, were significantly associated with higher general intelligence. Education also predicted higher decision speed, and decision speed partly mediated the effect of education on general intelligence. These findings suggest that over age of 80 years old, CR was a better predictor of driving-related cognitive abilities than age. Education was associated with better performance across different cognitive domains including processing speed.

Executive dysfunctions mediate between altered sensory processing and daily activity performance in older adults

BACKGROUND

Sensory processing is essential for the interaction with the environment and for adequate daily function. Sensory processing may deteriorate with aging and restrict daily activity performance. Aging may also affect Executive functions (EFs) which are critical for daily activity performance. Yet, most studies refer separately to the impacts of sensory processing or EFs and use clinical evaluations that do not necessarily reflect functional restrictions in real life. This study aims to describe the prevalence of altered sensory processing in the elderly as expressed in daily life scenarios and explore whether EFs mediate between altered sensory processing and daily activity performance in older adults.

METHODS

This cross-sectional study included 167 healthy independently functioning people aged 65 and above who were living in the community, had sufficient cognitive status and no symptoms of depression (based on the GDS and the MMSE). All participants completed a socio-demographic-health questionnaire, the Adolescent/Adult Sensory Profile, the Behavior Rating Inventory of Executive Function-Adult Version and the Daily Living Questionnaire.

RESULTS

Altered sensory processing, and mainly by the reduced ability to register and modulate sensory input from daily environment, were prevalent in older adults. Their impacts on daily activity performance were mediated by executive dysfunctions.

CONCLUSIONS

Executive dysfunctions may worsen the negative effects of altered sensory processing on daily activity performance in older adults. The interaction between EFs and sensory processing should receive growing attention in intervention and prevention programs for older adults, with the emphasis on their expressions and implications on peoples' function in real life context.

A Frontal Neuropsychological Profile in Fitness to Drive

Traffic accidents are a global concern due to the elevated mortality rates of both drivers and pedestrians. The World Health Organization declared 2011-2020 as the Decade of Action for Road Safety, endorsing initiatives to reduce traffic-related deaths. Yet, despite these incentives, fatal accidents still occur. Different studies have linked deficits in executive functions to risky driving attitudes and crashes. The present study focuses on demographic, cognitive and personality factors, related to the prefrontal cortex, that are characteristic of drivers prone to risky behavior behind the wheel. The penalty Points System was used to classify drivers as "safe", with no point loss over a two-year period, or "risky", with full point loss during the same interval. A neuropsychological assessment of prefrontal cognitive functions was carried out on each group to identify variables associated with safe and risky behavior. Neuropsychological indexes were obtained from a continuous performance task without cue (Simple Attention), a continuous performance task with cue (Conditioned Attention), the Tower of Hanoi test and the Neurologically-related Changes in Personality Inventory (NECHAPI). A Discriminant Analysis (DA) found that education level, reaction times in Simple and Conditioned Attention, learning errors in the Tower of Hanoi and vulnerability in the personality test, best predicted whether drivers were likely to be in the safe or risky group. Finally, a cross-validation analysis performed on the same sample correctly classified 87.5% of the drivers. These data suggest that prefrontal dysfunction contributes to risky behavior behind the wheel. The inclusion of cognitive programs to identify and train drivers with this propensity could reduce risky driving, and consequently, save lives on the road.

Assessing Fitness-To-Drive among Older Drivers: A Comparative Analysis of Potential Alternatives to on-Road Driving Test

To enable older drivers to maintain mobility without endangering public safety, it is necessary to develop more effective means of assessing their fitness-to-drive as alternatives to an on-road driving test. In this study, a functional ability test, simulated driving test, and on-road driving test were carried out for 136 older drivers. Influencing factors related to fitness-to-drive were selected based on the correlation between the outcome measure of each test and the pass/fail outcome of the on-road driving test. Four potential alternatives combining different tests were considered and three modeling techniques were compared when constructing the fitness-to-drive assessment model for the elderly. As a result, 92 participants completed all of the tests, of which 61 passed the on-road driving test and the remaining 31 failed. A total of seven influencing factors from all types of tests were selected. The best model was trained by the technique of gradient boosted machine using all of the seven factors, generating the highest accuracy of 92.8%, with sensitivity of 0.94 and specificity of 0.90. The proposed fitness-to-drive assessment method is considered an effective alternative to the on-road driving test, and the results offer a valuable reference for those unfit-to-drive older drivers to either adjust their driving behavior or cease driving.

The Effects of Age, Distraction, and Simulated Central Vision Impairment on Hazard Detection in a Driving Simulator

SIGNIFICANCE

Despite similar levels of visual acuity and contrast sensitivity reductions, simulated central vision impairment increased response times to a much greater extent in older than in younger participants.

PURPOSE

Driving is crucial for maintaining independence in older age, but age-related vision impairments and in-vehicle auditory distractions may impair driving safety. We investigated the effects of age, simulated central vision impairment, and auditory distraction on detection of pedestrian hazards.

METHODS

Thirty-two normally sighted participants (16 younger and 16 older) completed four highway drives in a simulator and pressed the horn whenever they saw a pedestrian. Pedestrians ran toward the road on a collision course with the approaching vehicle. Simulated central vision impairment was achieved by attaching diffusing filters to a pair of laboratory goggles, which reduced visual acuity to 20/80 and contrast sensitivity by 0.35 log units. For drives with distraction, subjects listened to an audiobook and repeated out loud target words.

RESULTS

Simulated central vision impairment had a greater effect on reaction times (660-millisecond increase) than age (350-millisecond increase) and distraction (160-millisecond increase) and had a greater effect on older than younger subjects (828- and 492-millisecond increase, respectively). Simulated central vision impairment decreased safe response rates from 94.7 to 78.3%. Distraction did not, however, affect safety because older subjects drove more slowly when distracted (but did not drive more slowly with vision impairment), suggesting that they might have perceived greater threat from the auditory distraction than the vision impairment.

CONCLUSIONS

Older participants drove more slowly in response to auditory distraction. However, neither older nor younger participants adapted their speed in response to simulated vision impairment, resulting in unsafe detections. These results underline the importance of evaluating safety of responses to hazards as well as reaction times in a paradigm that flexibly allows participants to modify their driving behaviors.

Reliability and Validity of a Method for Assessment of Executive Functions in Drivers

The quality of drivers’ performance is one of the crucial components related to road safety. One of the key cognitive characteristics related to the ability to drive safely are executive functions. The main goal of the presented research is to propose a new method (Trace-route task) for assessment of executive functions in drivers. The present article discusses the results of two consecutive studies. Study one aims to determine the validity and reliability of the method used and includes 134 participants, equally divided in two groups—people with disturbances in executive functions and people from the general population. Study two aims to assess the ability of the method to distinguish drivers with risky behavior. It includes 1440 participants divided in two groups—people with and without actual risky driving behavior. The results from the studies show that people with different neurological or psychiatric diseases and drivers with different road violations demonstrate worse planning ability, working memory, decision making, and cognitive flexibility. This data show that the trace-route task method is a valid and reliable instrument for assessing executive functions and has the ability to distinguish people with risky driving behavior from those who drive safely. This study reveals that the proposed method can be used for implementation in the area of traffic psychology.

Cognitive and neural plasticity in old age: A systematic review of evidence from executive functions cognitive training

Cognitive training is a popular intervention aimed at attenuating age-related cognitive decline, however, the effects of this intervention on brain structure and function have not been thoroughly explored. Core executive functions (working memory, inhibition, cognitive flexibility) are dependent upon prefrontal brain regions-one of the most vulnerable areas of age-related decline. They are also implicated in numerous cognitive processes and higher-order functions. Training executive functions should therefore promote cognitive and neural enhancements in old age. This systematic review examined the effects of executive functions training on brain and cognition amongst healthy older adults across 20 studies. Behavioral performance consistently improved on trained cognitive tasks, though mixed findings were reported for untrained tasks. Training-related structural changes were reported, evidenced through increases in grey matter and cortical volume. Functional changes were not consistent, though a general pattern of increased subcortical and decreased frontal and parietal activation emerged across studies, indicating that training may potentially reduce reliance on compensatory neural mechanisms. Training executive functions appears to promote cognitive and neural plasticity in old age, though further research is required to develop a more comprehensive framework which connects and elucidates the mechanisms underlying cognitive training, cognitive transfer, and cognitive aging.

Exploring the contribution of executive functions to on-road driving performance during aging: A latent variable analysis

With the aging of the population the issue of older drivers safety has gained importance in recent years. Age-related cognitive decline is frequently cited as the main cause of unsafe driving performance in older drivers.

OBJECTIVE

The present study investigated how executive functions (EFs), measured as latent variables, are related to on-road driving performance during aging.

METHOD

One hundred and twenty-six participants aged from twenty to eighty-two, completed a two hundred and forty-seven km on-road driving test and a set of executive tasks selected to tap three often postulated EFs: inhibition (inhibiting prepotent responses), updating (updating working memory representations), and shifting (shifting task sets).

RESULTS

Confirmatory factor analysis reproduces previous results obtained by Miyake et al. (2000), Miyake and Friedman (2012) of unity and diversity of EFs in an adult life span sample. Structural equation modeling suggested that on-road driving performance was related to inhibition. Furthermore, findings indicate that the age-related driving performance decline in normal aging may be mediated by the inhibition function.

CONCLUSIONS

The results highlight the importance of a proper method to assess executive functioning in a specific domain as well as emphasising the major role of those functions in driving performance while aging.

Newly Developed TV-Based Cognitive Training Games Improve Car Driving Skills, Cognitive Functions, and Mood in Healthy Older Adults: Evidence From a Randomized Controlled Trial

Background: Cognitive training in a laboratory improves car driving skills of older car drivers. However, it remains unclear whether other types of cognitive training at home have beneficial effects on driving skills. Using our developed cognitive training games that can be played on a television with a set-top box in a person’s home, we investigated the effects of a 6-week cognitive training program on driving skills, which included on-road evaluation (primary outcome), and cognitive functions and emotional states (secondary outcome) in older people.

Methods: In this double-blinded randomized control trial (RCT), 60 older licensed drivers were randomly assigned into one of the two groups: a cognitive training game for car driving (CTCD) group and an active control cognitive training game (ACT) group. Participants in the CTCD group played the CTCD (processing speed, dual attention, and speed prediction) for 20 min in five sessions per week for 6 weeks. Participants in the ACT group played the ACT (selecting the larger number; selecting a number from largest to smallest; play a game of rock, article, scissors) for 20 min in five sessions per week for 6 weeks. We measured driving skills, various cognitive functions, and emotional states before and after the 6-week intervention period.

Results: Our main results showed that compared to the ACT group, the CTCD group demonstrated improved driving skills (adjusted p = 0.034). Moreover, the CTCD group demonstrated improved inhibition (stroop, adjusted p = 0.042: reverse Stroop, adjusted p = 0.043) and processing speed performance symbol search (SS), adjusted p = 0.049; digit symbol coding (adjusted p = 0.047), compared to the ACT group. The CTCD group scored higher on vigor–activity mood (adjusted p = 0.041) as measured using the Profile of Mood State.

Discussion: This randomized controlled trial provides scientific evidence for the benefits of the 6-week CTCD program on driving skills and cognitive functions, such as processing speed, inhibition, and vigor–activity mood, in healthy older people. Our results suggest that cognitive training is useful to improve the driving skills of older adults.

Trial registration: This trial was registered at The University Hospital Medical Information Network Clinical Trials Registry (UMIN 000029769). Registered 31 October 2017, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000034010

The Context of Caution: An Examination of Age, Social Context, and Sex on Measures of Inhibitory Control and Risky Decision-Making

Understanding how older adults successfully navigate complex choices like driving requires the consideration of processing speed, inhibitory control, attentional processes, and risk management, and the context within which these decisions occur. The current study employed the Flanker task, the Stoplight task, and a personality inventory with 43 younger adults and 49 older adults either while they were alone or being observed by two same-sex, similarly aged peers. On the Flanker task, older adults performed more slowly, but with comparable accuracy. On the Stoplight task, there was a significant main effect of Context, and an Age-Group by Sex interaction, even after controlling for response time: All groups had a greater number of crashes when alone, and young adult males had significantly more crashes than any other group. These results emphasize the importance of considering the broader context of decision-making.

Aiding medical professionals in fitness-to-drive screenings for elderly drivers: development of an office-based screening tool

ABSTRACTBackground:Elderly drivers are an increasing group in society. Previous research has found that functional and cognitive abilities are more important for driving abilities than biological age. In an attempt to conserve independent mobility for elderly drivers, many researchers have focused on elderly drivers diagnosed with cognitive decline (mild cognitive impairment or mild Dementia). This study is the first to focus on elderly drivers with cognitive complaints or suspected of diminished fitness to drive by an (in)formal caregiver as an at-risk group.

METHODS

The main objective of this study was to develop a fitness to drive screening tool for elderly drivers to be used in a doctor's office. Furthermore, this study investigated the additional value of driving simulator tests in the assessment of fitness to drive. Both screenings (functional abilities and driving simulator test) were benchmarked against the official Belgian fitness to drive licensing procedure.

RESULTS

One-hundred thirty-six elderly drivers participated in a functional abilities screening, a driving simulator assessment and an on-road driving test. Sixty-five percent of the sample was considered fit to drive. Visual acuity, physical flexibility, and knowledge of road signs were found to be the best predictive set of tests for the on-road fitness to drive outcome. A performance based driving simulator assessment increased predictive accuracy significantly.

CONCLUSION

The proposed screening procedure saves part of the at-risk elderly driver population from stressful and costly on-road driving evaluations. This procedure provides more information of an individual driver's specific driving parameters. This opens doors for personalized older driver training to maintain independent mobility in later life.

Default-mode network dynamics are restricted during high speed discrimination in healthy aging: Associations with neurocognitive status and simulated driving behavior

Numerous daily tasks, including car driving, require fine visuospatial tuning. One such visuospatial ability, speed discrimination, declines with aging but its neural underpinnings remain unknown. In this study, we use fMRI to explore the effect of aging during a high speed discrimination task and its neural underpinnings, along with a complete neuropsychological assessment and a simulated driving evaluation in order to examine how they interact with each other through a multivariate regression approach. Beyond confirming that high speed discrimination performance is diminished in the elderly, we found that this deficit might be partly due to a lack of modulation in the activity and connectivity of the default mode network (DMN) in this age group, as well as an over-recruitment of frontoparietal and cerebellar regions, possibly as a compensatory mechanism. In addition, younger adults tended to drive at faster speeds, a behavior that was associated to adequate DMN dynamics and executive functioning, an effect that seems to be lost in the elderly. In summary, these results reveal how age-related declines in fine visuospatial abilities, such as high speed discrimination, were distinctly mediated by DMN functioning, a mechanism also associated to speeding behavior in a driving simulator.

Can Driving-Simulator Training Enhance Visual Attention, Cognition, and Physical Functioning in Older Adults?

Virtual reality offers a good possibility for the implementation of real-life tasks in a laboratory-based training or testing scenario. Thus, a computerized training in a driving simulator offers an ecological valid training approach. Visual attention had an influence on driving performance, so we used the reverse approach to test the influence of a driving training on visual attention and executive functions. Thirty-seven healthy older participants (mean age: 71.46 ± 4.09; gender: 17 men and 20 women) took part in our controlled experimental study. We examined transfer effects from a four-week driving training (three times per week) on visual attention, executive function, and motor skill. Effects were analyzed using an analysis of variance with repeated measurements. Therefore, main factors were group and time to show training-related benefits of our intervention. Results revealed improvements for the intervention group in divided visual attention; however, there were benefits neither in the other cognitive domains nor in the additional motor task. Thus, there are no broad training-induced transfer effects from such an ecologically valid training regime. This lack of findings could be addressed to insufficient training intensities or a participant-induced bias following the cancelled randomization process.

How to quantitatively evaluate safety of driver behavior upon accident? A biomechanical methodology

How to evaluate driver spontaneous reactions in various collision patterns in a quantitative way is one of the most important topics in vehicle safety. Firstly, this paper constructs representative numerical crash scenarios described by impact velocity, impact angle and contact position based on finite element (FE) computation platform. Secondly, a driver cabin model is extracted and described in the well validated multi-rigid body (MB) model to compute the value of weighted injury criterion to quantitatively assess drivers’ overall injury under certain circumstances. Furthermore, based on the coupling of FE and MB, parametric studies on various crash scenarios are conducted. It is revealed that the WIC (Weighted Injury Criteria) value variation law under high impact velocities is quite distinct comparing with the one in low impact velocities. In addition, the coupling effect can be elucidated by the fact that the difference of WIC value among three impact velocities under smaller impact angles tends to be distinctly higher than that under larger impact angles. Meanwhile, high impact velocity also increases the sensitivity of WIC under different collision positions and impact angles. Results may provide a new methodology to quantitatively evaluate driving behaviors and serve as a significant guiding step towards collision avoidance for autonomous driving vehicles.

Driving simulator scenarios and measures to faithfully evaluate risky driving behavior: A comparative study of different driver age groups

To investigate the links between mental workload, age and risky driving, a cross-sectional study was conducted on a driving simulator using several established and some novel measures of driving ability and scenarios of varying complexity. A sample of 115 drivers was divided into three age and experience groups: young inexperienced (18-21 years old), adult experienced (25-55 years old) and older adult (70-86 years old). Participants were tested on three different scenarios varying in mental workload from low to high. Additionally, to gain a better understanding of individuals' ability to capture and integrate relevant information in a highly complex visual environment, the participants' perceptual-cognitive capacity was evaluated using 3-dimensional multiple object tracking (3D-MOT). Results indicate moderate scenario complexity as the best suited to highlight well-documented differences in driving ability between age groups and to elicit naturalistic driving behavior. Furthermore, several of the novel driving measures were shown to provide useful, non-redundant information about driving behavior, complementing more established measures. Finally, 3D-MOT was demonstrated to be an effective predictor of elevated crash risk as well as decreased naturally-adopted mean driving speed, particularly among older adults. In sum, the present experiment demonstrates that in cases of either extreme high or low task demands, drivers can become overloaded or under aroused and thus task measures may lose sensitivity. Moreover, insights from the present study should inform methodological considerations for future driving simulator research. Importantly, future research should continue to investigate the predictive utility of perceptual-cognitive tests in the domain of driving risk assessment.

Gender effect on driving cessation in pre-dementia and dementia phases: results of the 3C population-based study

OBJECTIVES

Aging entails deterioration in sensory, physical, and cognitive functions, raising doubt in the driving capacity of older drivers, especially when the deficits are severe, as in dementia. Many older drivers, especially women, adapt their driving habits in order to compensate for these deficits and eventually stop driving. The present prospective study assessed driving cessation in men and women throughout the dementia process, including a 2-year pre-dementia phase.

METHODS

The study was based on a three-city cohort of subjects who were aged 65 years and older in 2000 and followed for more than 10 years. Active dementia detection was conducted at each follow-up. The probability of driving cessation was assessed in men and women during the 2-year pre-dementia phase and until 5 years after diagnosis.

RESULTS

In the 2-year pre-dementia phase, both men and women ceased driving earlier than drivers with no central nervous system pathology (p < 0,001), and women ceased driving earlier than men. A total of 45% of men and 74% of women had already ceased driving at dementia diagnosis. In contrast, the probability of cessation within 3 years after diagnosis was similar between men and women.

CONCLUSION

The study showed that, in this French urban population, few demented drivers, especially women, were still driving after diagnosis. Those who continued to drive 3 years after the diagnosis all had Alzheimer-type dementia. There is certainly a need for physicians to help these drivers to adapt their driving activity to their deficits and to prepare them to stop driving. Copyright © 2016 John Wiley & Sons, Ltd.

Texting while driving, executive function, and impulsivity in college students

The purpose of the present study was to investigate the cognitive processes underlying texting while driving. A sample of 120 college students completed a survey to assess how frequently they send and read a text message while driving. Based on this information, students were assigned to one of two groups: 20 students who frequently text while driving and 20 matched-control students who infrequently text while driving but were similar in gender, age, years of education, and years driving. The groups were compared on the extent to which they differed in self-reported measures of executive function and impulsivity. The groups were also compared on a behavioral measure of impulsivity: the extent to which they discounted hypothetical monetary rewards as a function of the delay. For this measure, the students made repeated choices between smaller monetary rewards available immediately and larger rewards available after delays ranging from 1 week to 6 months. The results show that the group of students who frequently text while driving showed (a) significantly lower levels of executive function and (b) higher levels of self-reported impulsivity, although the groups did not differ significantly on the behavioral measure of impulsivity. These results support a general conclusion that drivers with lower levels of executive function and higher levels of impulsivity are more likely to text while driving.

Exploring associations between self-regulatory mechanisms and neuropsychological functioning and driver behaviour after brain injury

The objective of this prospective one-year follow-up study was to explore the associations between self-regulatory mechanisms and neuropsychological tests as well as baseline and follow-up ratings of driver behaviour. The participants were a cohort of subjects with stroke and traumatic brain injury (TBI) who were found fit to drive after a multi-disciplinary driver assessment (baseline). Baseline measures included neuropsychological tests and ratings of self-regulatory mechanisms, i.e., executive functions (Behavior Rating Inventory of Executive Function-Adult Version; BRIEF-A) and impulsive personality traits (UPPS Impulsive Behavior Scale). The participants rated pre-injury driving behaviour on the Driver Behaviour Qestionnaire (DBQ) retrospectively at baseline and after one year of post-injury driving (follow-up). Better performance on neuropsychological tests was significantly associated with more post-injury DBQ Violations. The BRIEF-A main indexes were significantly associated with baseline and follow-up ratings of DBQ Mistakes and follow-up DBQ Inattention. UPPS (lack of) Perseverance was significantly associated with baseline DBQ Inattention, whereas UPPS Urgency was significantly associated with baseline DBQ Inexperience and post-injury DBQ Mistakes. There were no significant changes in DBQ ratings from baseline (pre-injury) to follow-up (post-injury). It was concluded that neuropsychological functioning and self-regulatory mechanisms are related to driver behaviour. Some aspects of driver behaviour do not necessarily change after brain injury, reflecting the influence of premorbid driving behaviour or impaired awareness of deficits on post-injury driving behaviour. Further evidence is required to predict the role of self-regulatory mechanisms on driver behaviour and crashes or near misses.

Not all minds wander equally: The influence of traits, states and road environment factors on self-reported mind wandering during everyday driving

Inattention is a road safety problem, but few studies have focused specifically on mind wandering during everyday driving. This paper explores differences in self-reported mind wandering according to driver demographic characteristics (including age and gender), cognitive traits (such as tendency toward cognitive failure or mindful attention), states (such as feeling tired or stressed) and road environment factors (such as route familiarity). Five hundred and two participants (113 male, average age 44.4 years, SD=14.0years) completed a series of questionnaires (Mindful Attention and Awareness Scale (MAAS), Cognitive Failures Questionnaire (CFQ) and Driver Behaviour Questionnaire (DBQ)), as well as study-specific questions about mind wandering during different personal states and across a range of road and traffic situations. All respondents reported mind wandering during driving at least some of the time. Mind wandering was more likely to be reported on familiar roads than on unfamiliar roads and when drivers are tired. Drivers who reported relatively more mind wandering were younger, reported less mindful attention in daily life, more cognitive failures, and more driving violations and lapses. Together, the findings suggest that mind wandering is common in everyday driving, however any link with crash risk remains unclear. Future research using self-report and naturalistic methods could provide more insight into relationships between mind wandering, error and crash risk.

Non-illness-related factors contributing to traffic safety in older drivers: a literature review

BACKGROUND/STUDY CONTEXT: Older drivers are at increased risk of becoming involved in car crashes. Contrary to well-studied illness-related factors contributing to crash risk, the non-illness-related factors that can influence safety of older drivers are underresearched.

METHODS

Here, the authors review the literature on non-illness-related factors influencing driving in people over age 60. We identified six safety-relevant factors: road infrastructure, vehicle characteristics, traffic-related knowledge, accuracy of self-awareness, personality traits, and self-restricted driving.

RESULTS

The literature suggests that vehicle preference, the quality of traffic-related knowledge, the location and time of traffic exposure, and personality traits should all be taken into account when assessing fitness-to-drive in older drivers. Studies indicate that self-rating of driving skills does not reliably predict fitness-to-drive.

CONCLUSIONS

Most factors discussed are adaptable or accessible to training and collectively may have the potential to increase traffic safety for older drivers and other road users.

Effects of shrinkage of the visual field through ageing on parking performance: a parametric manipulation of salience and relevance of contextual components

The Master Activation model of attention (Michael, Vairet, and Fernandez, Capture attentionnelle en vision: La saillance, la pertinence, et la balance cortico-sous-corticale. In: G. A. Michael (ed), Neuroscience cognitive de l'attention visuelle [Cognitive Neuroscience of Visual Attention], Solal, Marseille, pp. 165-201, 2007; Michael, Lété, and Ducrot, Trajectories of Attentional Development: An Exploration with the Master Activation Map Model, Developmental Psychology, 49:615-631, 2013) was used to study visual attention and driving behaviours of younger and older drivers while parking a car. The salience and the relevance of elements present in the parking environment were manipulated during parking manoeuvres. Different effects on manoeuvring were observed depending on driver characteristics such as age and the extent of the field of view (FV). It was found that the presence of a relevant element, such as a pedestrian, impaired parking performance only among older drivers with a narrower FV. The distinct effects of salience and relevance suggest that they had different statuses in attentional processing of manoeuvring drivers.

Personality and attitudes as predictors of risky driving among older drivers

Although there are several studies on the effects of personality and attitudes on risky driving among young drivers, related research in older drivers is scarce. The present study assessed a model of personality-attitudes-risky driving in a large sample of active older drivers. A cross-sectional design was used, and structured and anonymous questionnaires were completed by 485 older Italian drivers (Mean age=68.1, SD=6.2, 61.2% males). The measures included personality traits, attitudes toward traffic safety, risky driving (errors, lapses, and traffic violations), and self-reported crash involvement and number of issued traffic tickets in the last 12 months. Structural equation modeling showed that personality traits predicted both directly and indirectly traffic violations, errors, and lapses. More positive attitudes toward traffic safety negatively predicted risky driving. In turn, risky driving was positively related to self-reported crash involvement and higher number of issued traffic tickets. Our findings suggest that theoretical models developed to account for risky driving of younger drivers may also apply in the older drivers, and accordingly be used to inform safe driving interventions for this age group.

Behavioural ratings of self-regulatory mechanisms and driving behaviour after an acquired brain injury

OBJECTIVE

To explore whether measurements of self-regulatory mechanisms and cognition predict driving behaviour after an acquired brain injury (ABI).

DESIGN

Consecutive follow-up study.

PARTICIPANTS

At baseline participants included 77 persons with stroke and 32 persons with a traumatic brain injury (TBI), all of whom completed a multidisciplinary driving assessment (MDA). A follow-up cohort of 34 persons that succeeded the MDA was included. Baseline measurements: Neuropsychological tests and measurements of self-regulatory mechanisms (BRIEF-A and UPPS Impulsive Behaviour Scale), driving behaviour (DBQ) and pre-injury driving characteristics (mileage, compensatory driving strategies and accident rates). Follow-up measurements: Post-injury driving characteristics were collected by mailed questionnaires from the participants who succeeded the MDA.

METHODS

A MDA, which included a medical examination, neuropsychological testing and an on-road driving test, was considered in the decision for or against granting a driver's license. Self-regulatory mechanisms and driving behaviour were examined for research purposes only.

RESULTS

At baseline, self-regulatory mechanisms were significantly associated to aberrant driving behaviour, but not with neuropsychological data or with the outcome of the on-road driving test. Aspects of self-regulation were associated to driving behaviour at follow-up.

CONCLUSION

It is recommended that self-regulatory measurements should regularly be considered in the driving assessments after ABI.

The Big Five Personality Factors as Predictors of Driving Status in Older Adults

Objective: Although factors including cognitive and health status have been associated with driving cessation in older adults, the role of psychosocial variables is not well studied. Previous research on young adult drivers has suggested that personality may be related to driving behavior, but this study is among the first to explore the relationship between driving status and the Big Five Model of personality for older adults. Method: Data are from the Health and Retirement Study (2008 wave, n = 4,028). Descriptive, bivariate, and multiple logistic regression analyses were conducted. Results: Neuroticism (β = −0.4511, p < .001) and agreeableness (β = −0.5058, p < .001) were associated with decreased likelihood of driving; extraversion (β = 0.4588, p < .001), openness (β = 0.5903, p < .001), and conscientiousness (β = 0.4077, p < .001) were associated with increased likelihood of driving, although results were partially mediated by including known risk factors. People who limited their driving to nearby locations were the most different from those who no longer drove. Discussion: Personality adds a unique contribution to the prediction of late-life driving status.

The effects of age and workload on 3D spatial attention in dual-task driving

In the present study we assessed whether the limits in visual-spatial attention associated with aging affect the spatial extent of attention in depth during driving performance. Drivers in the present study performed a car-following and light-detection task. To assess the extent of visual-spatial attention, we compared reaction times and accuracy to light change targets that varied in horizontal position and depth location. In addition, because workload has been identified as a factor that can change the horizontal and vertical extent of attention, we tested whether variability of the lead car speed influenced the extent of spatial attention for younger or older drivers. For younger drivers, reaction time (RT) to light-change targets varied as a function of distance and horizontal position. For older drivers RT varied only as a function of distance. There was a distance by horizontal position interaction for younger drivers but not for older drivers. Specifically, there was no effect of horizontal position at any given level of depth for older drivers. However, for younger drivers there was an effect of horizontal position for targets further in depth but not for targets nearer in depth. With regards to workload, we found no statistically reliable evidence that variability of the lead car speed had an effect on the spatial extent of attention for younger or older drivers. In a control experiment, we examined the effects of depth on light detection when the projected size and position of the targets was constant. Consistent with our previous results, we found that drivers' reaction time to light-change targets varied as a function of distance even when 2D position and size were controlled. Given that depth is an important dimension in driving performance, an important issue for assessing driving safety is to consider the limits of attention in the depth dimension. Therefore, we suggest that future research should consider the importance of depth as a dimension of spatial attention in relation to the assessment of driving performance.

The relation between cognitive control and risky driving in young novice drivers

This study investigated if decreased cognitive control, reflected in response inhibition and working-memory performance, is an underlying mechanism of risky driving in young novice drivers. Thirty-eight participants aged 17 to 25 years old, with less than 1 year of driving experience, completed a simulated drive that included several risky driving measures. Measures of response inhibition and verbal working memory were negatively associated with the standard deviation of the lateral lane position. Response inhibition, but not working memory, was also negatively related with the detection of, reaction to, and crashes with road hazards. Unexpectedly, increased cognitive control did not always relate to decreased risky driving. Visuospatial working-memory performance related positively with yellow-light running and negatively with the minimal following distance inside the city center. The findings evidence the role of cognitive control in explaining risky driving in young novice drivers. This relationship, however, differed per cognitive function and per driving parameter. Implications for future research and traffic safety interventions are discussed.

Systematic review of the evidence for Trails B cut-off scores in assessing fitness-to-drive

Background

Fitness-to-drive guidelines recommend employing the Trail Making B Test (a.k.a. Trails B), but do not provide guidance regarding cut-off scores. There is ongoing debate regarding the optimal cut-off score on the Trails B test.

The objective of this study was to address this controversy by systematically reviewing the evidence for specific Trails B cut-off scores (e.g., cut-offs in both time to completion and number of errors) with respect to fitness-to-drive.

Methods

Systematic review of all prospective cohort, retrospective cohort, case-control, correlation, and cross-sectional studies reporting the ability of the Trails B to predict driving safety that were published in English-language, peer-reviewed journals.

Results

Forty-seven articles were reviewed. None of the articles justified sample sizes via formal calculations. Cut-off scores reported based on research include: 90 seconds, 133 seconds, 147 seconds, 180 seconds, and < 3 errors.

Conclusions

There is support for the previously published Trails B cut-offs of 3 minutes or 3 errors (the ‘3 or 3 rule’). Major methodological limitations of this body of research were uncovered including (1) lack of justification of sample size leaving studies open to Type II error (i.e., false negative findings), and (2) excessive focus on associations rather than clinically useful cut-off scores.

A randomized trial to evaluate the effectiveness of an individual, education-based safe transport program for drivers aged 75 years and older

BACKGROUND

There are concerns over safety of older drivers due to increased crash involvement and vulnerability to injury. However, loss of driving privileges can dramatically reduce independence and quality of life for older members of the community. The aim of this trial is to examine the effectiveness of a safe transport program for drivers aged 75 years and older at reducing driving exposure but maintaining mobility.

METHODS AND DESIGN

A randomised trial will be conducted, involving 380 drivers aged 75 years and older, resident in urban and semi-rural areas of North-West Sydney. The intervention is an education program based on the Knowledge Enhances Your Safety (KEYS) program, adapted for the Australian context. Driving experience will be measured objectively using an in-vehicle monitoring device which includes a global positioning system (GPS) to assess driving exposure and an accelerometer to detect rapid deceleration events. Participation will be assessed using the Keele Assessment of Participation (KAP). Data will be analysed on an intention-to-treat basis; the primary outcomes include driving exposure, rapid deceleration events and scores for KAP. Secondary outcomes include self-reported measures of driving, socialisation, uptake of alternative forms of transport, depressive symptoms and mood. A detailed process evaluation will be conducted, including examination of the delivery of the program and uptake of alternative forms of transport. A subgroup analysis is planned for drivers with reduced function as characterized by established cut-off scores on the Drivesafe assessment tool.

DISCUSSION

This randomised trial is powered to provide an objective assessment of the efficacy of an individually tailored education and alternative transportation program to promote safety of older drivers but maintain mobility.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12612000543886.

The influence of differences in the functioning of the neurocognitive attentional networks on drivers' performance

Considerable research efforts are currently being devoted to analysing the role that the attentional system plays in determining driving behaviour, with the ultimate objective of reducing the number of attention-related accidents. The present study aims to assess the influence of differences in the functioning of the three attentional networks (executive control, attentional orienting and alerting) when drivers have to deal with some common hazardous situations, for example, when an oncoming car or a pedestrian unexpectedly crosses their trajectory. Multiple measures of participants' attentional functioning were obtained from a computer-based neurocognitive test: the Attention Networks Test for Interactions and Vigilance (ANTI-V). These measures were compared to performance in a driving simulator where different types of hazardous situations were presented. Correlation and linear regression analyses revealed significant associations between individual attentional measures and driving performance in specific traffic situations. In particular, a higher attentional orienting score on the ANTI-V was associated with safer driving in situations where a single precursor anticipated the hazard source, whereas in complex situations with multiple potential hazard precursors, higher attentional orienting scores were associated with delayed braking. Additionally, partial evidence of a relationship between crash occurrence and the functioning of the executive control and the alerting networks was found. Overall, the current research would be helpful to better understand the role that each attentional network (executive control, attentional orienting and alerting) play in safe driving, and thus to develop efficient countermeasures to reduce attention-related crashes.

Age and inconsistency in driving performance

Research in cognitive neuropsychology suggests that investigation of the within-person variability, or inconsistency, of cognitive performance may provide valuable insights into ageing mental processes. It is rare though, for this interest in intraindividual variability to extend to everyday activities. As this may provide important information about driving behaviour, we therefore assessed age differences in driving inconsistency in younger (n=24, M age=21.29 years) and older (n=21, M age=71.24 years) persons who drove in residential, urban and motorway conditions in a fully immersive driving simulator. In measures of headway (maintaining a safe distance to a preceding vehicle) and lateral lane position, older drivers exhibited significantly greater performance inconsistency, and this was particularly marked in the faster motorway condition. Older drivers also recorded greater perceived mental demands associated with driving, and greater within-person variability across a range of cognitive measures. The findings suggest that age-related deficits in attentional and executive control may affect the consistency of driving performance in older persons. Discussion considers interventions to introduce in-vehicle systems to help maintain attention in older drivers, and to intervene when safety-critical boundaries are exceeded.