The ability of young,middle-aged and older drivers to inhibit visual and auditory distraction in a driving simulator task

Driver distraction is one major cause of road traffic accidents. In order to avoid distraction-related accidents it is important to inhibit irrelevant stimuli and unnecessary responses to distractors and to focus on the driving task, especially when unpredictable critical events occur. Since inhibition is a cognitive function that develops until young adulthood and decreases with increasing age, young and older drivers should be more susceptible to distraction than middle-aged drivers. Using a driving simulation, the present study investigated effects of acoustic and visual distracting stimuli on responses to critical events (flashing up brake lights of a car ahead) in young, middle-aged, and older drivers. The task difficulty was varied in three conditions, in which distractors could either be ignored (perception-only), or required a simple response (detection) or a complex Go-/NoGo-response (discrimination). Response times and error rates to the critical event increased when a simultaneous reaction to the distractor was required. This distraction effect was most pronounced in the discrimination condition, in which the participants had to respond to some of the distracting stimuli and to inhibit responses to some other stimuli. Visual distractors had a stronger impact than acoustic ones. While middle-aged drivers managed distractor inhibition even in difficult tasks quite well (i.e., when responses to distracting stimuli had to be suppressed), response times of young and old drivers increased significantly, especially when distractor stimuli had to be ignored. The results demonstrate the high impact of distraction on driving performance in critical traffic situations and indicate a driving-related inhibition deficit in young and old drivers.     

Evidence for the role of personality in the cognitive performance of older male drivers

ObjectivesThis study aimed to examine whether in older male drivers the level of information processing under increasing cognitive workload varies with the level of personality traits.MethodThe study involved 60 male, active drivers aged between 65 and 81 (M = 71, SD = 4.4). During passive driving they performed central (a test in the n-back scheme, in three cognitive workload levels) and peripheral (memorizing objects characteristic for road traffic) tasks presented simultaneously in the central and peripheral visual fields. A wide-angle high-fidelity collimated visual system was used to display visual stimuli. In the central task, the reaction time and its correctness were measured, while the peripheral task measured the number of memorized objects. The EPQ-R questionnaire was used to assess personality traits, and the memory functions were assessed using the MMSE test.ResultsAs the central task-induced cognitive workload increases, the performance of both central and peripheral tasks deteriorates. These tasks were performed less accurately by drivers with a higher level of psychoticism than those with a lower level of this trait. This dependency related to all levels of cognitive workload. In contrast, the drivers with a higher level of neuroticism showed a lower level of performance of the peripheral task than those with a low level of this trait. This dependency concerned only the central task with a medium cognitive workload.ConclusionThe level of personality traits, especially the ones related to the emotional sphere, contributed to the decrease in the effectiveness of action (longer reaction time, increase in the number of errors, decrease in the number of memorized objects) in the conditions of increasing cognitive workload. A higher level of neuroticism and psychoticism can be conducive to making errors on the road. This applies especially to situations that pose high demands on the driver’s cognitive system.     

Assessing the driving distraction effect of vehicle HMI displays using data mining techniques

With the rapid development of human–machine interface (HMI) systems in vehicles, driving distraction caused by HMI displays affects road safety. This study presents a data mining technique to model the four driving distraction indicators: speed deviation, lane departure standard deviation, dwell time, and mean glance time. Driving distraction data was collected on a real-car driving simulator. 3 secondary tasks in 13 mass produced cars were tested by 24 drivers. The random forest algorithm outperformed linear regression, extreme gradient boosting, and multi-layer perceptron as the best model, demonstrating good regression performance as well as good interpretability. The result of random forest showed that the importance of target speed is large for all driving distraction indicators. Among the variables of interaction and user interface design, less step and less on-screen distance of finger movement are efficient for lowering lane departure standard deviation and dwell time. The position of right point is another important variable, and should be between 37 and 47 degrees on a typical sample in this study. A larger angle leads to bigger lane departure, while a smaller angle leads to bigger mean glance time. Most variables of HMI display positioning themselves are not important. This study provides one driving distraction assessment method with a variable impact trend analysis for HMI secondary tasks in an early phase of product development.     

Prediction of effort and eye movement measures from driving scene components

For transitions of control in automated vehicles, driver monitoring systems (DMS) may need to discern task difficulty and driver preparedness. Such DMS require models that relate driving scene components, driver effort, and eye measurements. Across two sessions, 15 participants enacted receiving control within 60 randomly ordered dashcam videos (3-second duration) with variations in visible scene components: road curve angle, road surface area, road users, symbols, infrastructure, and vegetation/trees while their eyes were measured for pupil diameter, fixation duration, and saccade amplitude. The subjective measure of effort and the objective measure of saccade amplitude evidenced the highest correlations (r = 0.34 and r = 0.42, respectively) with the scene component of road curve angle. In person-specific regression analyses combining all visual scene components as predictors, average predictive correlations ranged between 0.49 and 0.58 for subjective effort and between 0.36 and 0.49 for saccade amplitude, depending on cross-validation techniques of generalization and repetition. In conclusion, the present regression equations establish quantifiable relations between visible driving scene components with both subjective effort and objective eye movement measures. In future DMS, such knowledge can help inform road-facing and driver-facing cameras to jointly establish the readiness of would-be drivers ahead of receiving control.     

A simulation sickness study on a driving simulator equipped with a vibration platform

Simulator sickness is a well-known side effect of driving simulation which may reduce the passenger well-being and performance due to its various symptoms, from pallor to vomiting. Numerous reducing countermeasures have been previously tested; however, they often have undesirable side effects. The present study investigated the possible effect of seat vibrations on simulator sickness. Three configurations were tested: no vibrations, realistic ones and some that might affect the proprioception. Twenty-nine participants were exposed to the three configurations on a four-minute long automated driving in a simulator equipped with a vibration platform. Simulator sickness was estimated thanks to the Simulator Sickness Questionnaire (SSQ) and to a postural instability measure. Results showed that vibrations help to reduce the sickness. Our findings demonstrate that some specific vibration configurations may have a positive impact on the sickness, thus confirming the usefulness of devices reproducing the road vibrations in addition to creating more immersion for the driver.     

A driving simulator study to assess driver performance during a car-following maneuver after switching from automated control to manual control

A review of the literature on autonomous vehicles has shown that they offer several benefits, such as reducing traffic congestion and emissions, and improving transport accessibility. Until the highest level of automation is achieved, humans will remain an important integral of the driving cycle, which necessitates to fully understand their role in automated driving. A difficult research topic involves an understanding of whether a period of automated driving is likely to reduce driver fatigue rather than increase the risk of distraction, particularly when drivers are involved in a secondary task while driving. The main aim of this research comprises assessing the effects of an automation period on drivers, in terms of driving performance and safety implications. A specific focus is set on the car-following maneuver. A driving simulator experiment has been designed for this purpose. In particular, each participant was requested to submit to a virtual scenario twice, with level-three driving automation: one drive consisting of Full Manual Control Mode (FM); the other comprising an Automated Control Mode (AM) activated in the midst of the scenario. During the automation mode, the drivers were asked to watch a movie on a tablet inside the vehicle. When the drivers had to take control of the vehicle, two car-following maneuvers were planned, by simulating a slow-moving vehicle in the right lane in the meanwhile a platoon of vehicles in the overtaking lane discouraged the passing maneuver. Various driving performances (speeds, accelerations, etc.) and surrogate safety measures (PET and TTC) were collected and analysed, focusing on car-following maneuvers. The overall results indicated a more dangerous behavior of drivers who were previously subjected to driving automation; the percentage of drivers who did not apply the brakes and headed into the overtaking lane despite the presence of a platoon of fast-moving vehicles with unsafe gaps between them was higher in AM drive than in FM drive. Conversely, for drivers who preferred to brake, it was noted that those who had already experienced automated driving, adopted a more careful behavior during the braking maneuver to avoid a collision. Finally, with regard to drivers who had decided to overtake the braking vehicle, it should be noted that drivers who had already experienced automated driving did not change their behavior whilst overtaking the stopped lead vehicle.     

Approaching to a structural model of impulsivity and driving anger as predictors of risk behaviors in young drivers

Due to the high rates of traffic accidents in young drivers, psychology studies identify road anger as an important factor associated to risk driving behaviors, in order to know which psychological variables can predict road anger, the literature suggest impulsivity as an individual condition related to anger. The objective of this research is to obtain an explanatory model of risk driving as a result of the relationship of impulsivity, road anger expression and the control of impulsivity and anger. A sample of 407 subjects, both sexes drivers were surveyed, obtaining a structural equation model with acceptable adjustment values. The model showed that control of impulsivity and anger predict impulsivity (β = −0.25) and physical expression of anger (β = −0.50), Impulsivity also showed predictive capacity towards the physical expression of anger (β = 0.29), and the physical expression of anger towards risk driving behaviors (β = 0.89). Due to the findings it is suggested the implementation of social programs that promote the development of anger regulatory skills and impulse control, as part of the preventive actions of road accidents.     

Factor structure and measurement invariance of the multidimensional driving style inventory across gender and age: An ESEM approach

The Multidimensional Driving Style Inventory (MDSI) is the most comprehensive measure of typical driving behavior to date and has been frequently used to compare driving styles across different groups of drivers, particularly between gender- and age-related groups. However, the factor structure of MDSI has not been clearly established and its measurement invariance has not been demonstrated. The goal of the present study was to examine the internal structure and measurement invariance of the MDSI across gender and age. A sample of 1277 drivers from Argentina responded to the Argentinian version of the MDSI. Exploratory structural equation modeling (ESEM) was used to test the factor structure and measurement invariance across females (n = 602) and males (n = 675), and across young (18–29, n = 558), adult (30–49, n = 395) and older (50 and older, n = 317) drivers. The results showed that a 36-item six-factor ESEM model represented by risky, angry, dissociative, anxious, distress-reduction and careful and patient driving styles was the best model based on fit indices and interpretability. Configural, weak and strong invariance of the six-factor ESEM model across gender and age was also supported. The MDSI in its Argentinian version is equivalent across gender and age, supporting the validity of previous research findings examining gender and age differences in driving styles. Future studies should examine the measurement invariance of the MDSI across other relevant driving-related variables.     

The relationship between cognitive function and hazard perception in younger drivers

Driving is a complex task; with research suggesting cognitive function plays a significant role in driver behaviour. Recent studies have investigated the role of cognitive function in younger drivers who are experiencing brain maturation and are over-represented in crash statistics. Emerging evidence suggests poor cognitive functioning is one explanation for this high crash risk. For younger drivers, the relationship between cognitive function and driving ability has been consistently shown for speeding and lane deviations. However, the driving skill most consistently linked to crash involvement is hazard perception, which is the ability to anticipate and respond to potentially dangerous traffic situations. The aim of this study was to investigate the cognitive correlates of hazard perception in younger drivers. Seventy-nine undergraduate students completed a hazard perception test and a battery of cognitive tests that have previously demonstrated a relationship with safe driving. The newly created hazard perception test measured accuracy of hazard identification, response times when anticipating the hazard, and response times when taking action to avoid the hazard. Hazard perception accuracy was significantly related to visuo-spatial skills, executive functioning and global cognitive status. Anticipation response times were significantly related to inhibitory control, with no significant relationship found between cognitive function and action response times. These findings are discussed in line with limitations in the study. Future research into the role of specific cognitive domains could lead to the enhancement of hazard perception testing for licensing with cognitive training and assessment, with the potential to reduce the crash risk of vulnerable younger drivers.     

A driving simulation study to investigate the information threshold of graphical variable message signs based on visual perception characteristics of drivers

Graphical variable message signs (VMSs) are infrastructure-based advanced traveler information systems widely used to provide drivers with real-time traffic condition information about a road section or area. However, there is a lack of research on the suitable volume of information to be shown on graphical VMSs. In practice, an overload of VMS information commonly exists, especially on China’s highways. Building on our earlier findings obtained through surveys and static cognitive experiments, this study introduces the use of dynamic simulation experiments to assess the influence of the volume of information (i.e., number of roads displayed) on graphical VMSs from the perspective of drivers’ visual perception characteristics. Thirty-two drivers participated in the driving simulation experiment and questionnaires. Five indexes, including legibility speed, legibility distance, legibility time, comprehension accuracy, and driver subjective scoring, were thoroughly analyzed to evaluate their relationships to different volumes of information (i.e., four, five, and six roads shown on a VMS). The results show that the legibility distance notably decreased with increasing volumes of information. The comprehension accuracy decreased significantly when the number of roads shown increased to six. The legibility speed, legibility time, and subjective scoring also deteriorated as the number of roads displayed on the VMS increased. The index scores were evaluated, in combination with the data of the drivers’ subjective scoring, data-based statistical analyses, and comprehensive evaluations using the TOPSIS method, to recommend that five is the recommended maximum number of roads to be shown on a graphical VMS. The results of this study support the goal of providing understandable and effective messages for drivers by addressing issues relating to how much information should be displayed on a VMS. These findings provide a basis for policy development to ensure consistent and practical designs of graphical VMSs on highways.