Effects of route familiarity on drivers’ psychological conditions: Based on driving behaviour and driving environment

Route familiarity affects a driver’s mental state and indirectly affects traffic safety; however, this important factor is easily overlooked. Previous research on route familiarity has only analysed psychological states in terms of unfamiliarity and familiarity, the influence of driving behaviour and driving environment on psychological states has been ignored. As a result, the mechanisms through which the route familiarity influence driver psychological states, and vice versa, are unclear. This study proposes a quantitative framework for studying driver psychological condition and route familiarity using experimental data from a real driving task and driving environment data. The experimental data included 1022 observations obtained by 23 participants over 7 consecutive trials on 6 unfamiliar experimental routes with large differences in scenarios; environmental data were automatically extracted after segmenting a driving video through the Dilated Residual NetWorks model. The results reveal that (1) the relationship between the driver’s psychological condition and route familiarity is not monotonic and is different for straight and turning sections; (2) the driver’s psychological condition is influenced by the visual scene elements and the type of road section, and the results of the multivariate regression analysis quantified the variability of the influence; and (3) unlike a majority of findings on distracted driving, our study suggest that the driver’s attention to the external environment in the urban distracted driving state will gradually approach a ‘distraction threshold’, and the time and size of the ‘distraction threshold’ are influenced by the driver. This study can further the development of urban traffic safety research and help urban designers plan and improve urban landscapes to ensure drivers maintain stable mental states when they drive.     

Effect of electronic device use while driving on cardiovascular reactivity

Motor vehicle collisions are the leading cause of death in people ages 5–34 in the US, and secondary task engagement, such as talking on a cell phone, is a leading contributor to motor vehicle collisions. The negative effects of secondary task engagement on driving performance has become a prominent recent topic of study given the increasing amount of time drivers engage in distracted driving. However, few studies have examined the effects of secondary task engagement while driving on health related outcomes such as cardiovascular reactivity. Cardiovascular reactivity, as measured by heart rate and blood pressure, has been used in previous studies as a means of measuring effort in task engagement as well as a means to predict cardiovascular disease and stroke. This study investigates the effect of secondary task (talking on a cell phone, texting, and driving with no task) while driving in a simulator on cardiovascular reactivity. Using difference scores between baseline (a period of inactivity) and stimulus (driving with no task and driving with secondary tasks), a repeated measures analysis of variance using a mixed model approach was used to determine the effect of secondary task on cardiovascular reactivity. Findings indicated that talking on a cell phone while driving significantly increased cardiovascular reactivity via heart rate and blood pressure compared to driving with no task. Texting while driving did not differ significantly from driving with no task. This study demonstrates the need for more research on the long term effects of secondary tasks while driving on cardiovascular reactivity and for assessing the risks associated with secondary task use while driving on developing cardiovascular disease or stroke.     

Driving distraction at night: The impact of cell phone use on driving behaviors among young drivers

Currently, young drivers are more likely than other drivers to use cell phones while driving at night, which has become a major cause of road crashes. However, limited attention has been given to distracted nighttime driving. Therefore, the aim of this study was to explore the interaction effect of cell phone use and time of day (daytime and nighttime) on young drivers’ car-following performance. Forty-three young drivers engaged in a driving simulator experiment with a within-subject design that included three distractions (no distraction, talking and texting on a cell phone) and two times of day. This paper applied non-parametric tests to analyze the data and obtained the following results: (1) the standard deviation of lane position (SDLP) did not significantly differ at either time of day under no distraction, but it was significantly higher at night on straight roads and large-radius curves after introducing distractions. In addition, participants drove faster and gave less headway on small-radius curves under both distractions at night; (2) texting significantly increased the SDLP, while there was less lateral variation during the talking tasks than under no distraction on simple road sections; and (3) compared with the experienced drivers, the novice drivers drove faster during the talking tasks on small-radius curves, but there was no significant difference between groups during the texting tasks. These findings provide both theoretical and practical implications for related policy makers to enhance traffic safety.     

Revised reinforcement sensitivity theory: The impact of FFFS and stress on driving

This study investigated the effect of a fear-based personality trait, as conceptualized in Gray’s revised reinforcement sensitivity theory (RST) by the strength of the Fight/Flight/Freeze system (FFFS), on young people’s driving simulator performance under induced psychosocial stress. Seventy-one young drivers completed the Jackson-5 questionnaire of RST traits, followed by a psychosocial stress or relaxation induction procedure (random allocation to groups) and then a city driving simulator task. Some support was found for the hypothesis that higher FFFS sensitivity would result in poorer driving performance under stress, in terms of significantly poorer hazard responses, possibly due to an increased attentional focus on the aversive cues inherent in the stress induction leaving reduced attentional capacity for the driving task. These results suggest that stress may lead to riskier driving behaviour in individuals with fearful RST personality styles.     

The influence of music genres on the driving behaviour of young drivers and their visual scanning of the environment

Recently, distractions have been recognized as a significant risk factor in road traffic. This simulator study aims to investigate how different music genres affect the driving behaviour of young drivers and their visual scanning of the environment in urban settings. The genres considered were Croatian pop, foreign pop, classical music, metal, and Balkan folk music, while on one road section there was no music. The research sample consisted of 61 participants (44 males and 17 females) with a mean age of 24.58 years and a mean driving experience of 5.25 years. The influence of music on the drivers’ behaviour was analysed on the basis of the data collected from the driving simulator, eye tracking glasses, and structured observation during driving sessions. It was found that the highest average speed (around 60 km/h) was recorded while the participants were listening to Balkan folk and metal music, while other music genres, as well as the “no music” condition, influenced driving speed in a similar way to one another and the participants drove at 50 km/h on average. Furthermore, the results suggest that the music genre also affects how drivers visually scan the environment (the number of gazes classified as fixations and number of road signs looked at). The findings obtained may be used in road safety work and practical recommendations and further research are discussed.     

Aggressive thinking on the road. The mediation effect of aggressive thinking in the relationship between driving anger and aggression in Romanian drivers

Anger and aggression on the road have been pointed out as two of the main predictors of road accidents. However, while the emotional (anger) and behavioral (aggression) components of hostility have been deeply studied, the cognitive part has not received the same attention in this specific context. Thus, it is important to provide psychometric tools for assessing aggressive thoughts during driving, as the literature showed that cognitions play an important role in aggressive behavior. To this end, we asked Romanian drivers to answer three questionnaires: Driving Anger Thought Questionnaire (DATQ), the Driving Anger Scale (DAS) and the Driving Anger Expression Inventory (DAX), obtaining a total sample of 2133 answers. First, the psychometric properties of the DATQ were tested through a Confirmatory Factor Analysis, showing that the original 5-factor structure was maintained (Judgmental/Disbelieving Thinking, α = .93 both in men and women; Pejorative Labeling/Verbally Aggressive Thinking, α = .90 both in men and women; Physically Aggressive Thinking, α = .89 in men and α = .86 in women; Revenge/Retaliatory Thinking, α = .84 in men and α = .81 in women, and Adaptive/Constructive Expression, α = .84 in men and α = .82 in women). Then, we analyzed the mediation effect of angry thoughts between anger and aggression on the road, concluding that angry thoughts mediate this relationship. The main implications of the results are discussed.     

The mediation effect of emotion dysregulation in the relationship between anger and aggression on the road in a sample of Spanish drivers

Aggressive behaviour on the road is one of the most studied topics in human factors, given it has been related to both risky behaviour and traffic crashes. While previous research has proposed trait driving anger as one of the better predictors, mediation variables which could explain this relationship have not deserved attention. The current research aimed to explore the mediation effect of emotion regulation in this relationship. The sample consisted of 472 Spanish drivers, who completed a set of self-reports regarding trait driving anger, frequency of aggressive behaviours at the wheel, and difficulties in emotion regulation. The results showed significant relationship among the variables in almost all the cases. Furthermore, a SEM analysis showed that difficulties in emotion regulation significantly mediated the relationship between trait driving anger and each way of the aggressive behaviours (verbal, physical, using own vehicle, and displaced). These results have important implications in the design of strategies focused on the improvement of emotion regulation to reduce aggressive behaviours in drivers. Finally, the limitations of the study are commented.     

Evaluating the impact of real-time coaching programs on drivers overtaking cyclists

Innovative motor insurance schemes involve the use of on-board devices to collect kinematic driving data as part of the so-called ‘Pay-How-You-Drive’ schemes, which charge premiums based on drivers’ behavior. Some of these schemes also involve on-board coaching programs, which give real-time feedback to users.Here, we aimed to investigate the influence of motor insurance on-board real-time coaching programs on drivers’ behavior while overtaking cyclists, as motor vehicle/bicycle interactions are a relevant issue in road safety. The tested programs give real-time feedback to users on their acceleration, promoting smoother and safer driving styles.Data were collected with a driving simulator experiment involving 67 young drivers. The experiment was divided into two trials: in the first, participants drove as normally as possible without receiving any type of feedback; in the second, which took place one month later, they received feedback based on their driving behavior. Using data from the first trial, participants were clustered (k-mean approximation) into two groups, according to their driving style (aggressive vs. defensive). For each group, half of the drivers received contingent positive feedback (when a smooth driving event occurred) and the other half received contingent negative feedback (when a harsh driving event occurred). Feedback was presented in the form of auditory cues (for half of one group) or as visual cues (for the others). Thus, there were eight groups based on driving style, feedback type, and feedback modality.Multiple kinematic variables were studied with mixed ANOVA, and included not only clearance distances, speeds, and acceleration, but also the chosen overtaking strategy (accelerative vs. flying). Driving style, gender, car usage, feedback type and modality were considered as factors in the analysis.Results showed that the coaching programs had a significant positive effect, in terms of safety, reducing acceleration and speeds during the overtaking and inducing drivers to adopt the safer accelerative strategy. It was also particularly effective in improving the performance of aggressive drivers. These results are of high interest for real-world applications because they were obtained with a general-purpose coaching program; conversely, it might be impractical to develop dedicate programs for specific situations such as drivers overtaking cyclists.     

Fear and avoidance of driving among drivers involved in a road traffic crash. The role of traumatic fear and driving cognitions

Fear and avoidance of driving are possible consequences of involvement in road traffic crashes (RTCs). Few studies have assessed the factors associated with fear and avoidance of driving after an RTC. The aim of this present study is to investigate the relations among trauma appraisals of fear, negative driving cognitions, fear and avoidance of driving in a sample of people who experienced vehicle crashes. Further, the mediating role of negative driving cognitions in the relation between trauma appraisals, fear of driving and avoidance of driving was assessed. The sample was comprised of 116 drivers who had been involved in an RTC in the past two years. Negative driving cognitions positively predicted fear of driving and avoidance of driving. Moreover, negative driving cognitions mediated the relation among trauma appraisals of fear with fear of driving and avoidance of driving. The theoretical and practical implications of these results are discussed.     

The effect of a collision warning system on the driving performance of young drivers at intersections

This study investigated the manner in which the driving performance of young people was affected by a collision warning system when they encountered a driver running a red light at an intersection. Furthermore, the causal relationship among driving performance, traffic factors and intersection accidents was examined using Path Analysis. Participants drove a driving simulator with an intersection collision warning system (ICWS) in a simulated urban area. The driving performance measures recorded were reaction time, speed, lateral position deviation and crash events. Experimental results indicated that drivers who drove a vehicle with an ICWS audio signal at an intersection had a shorter reaction time, a lower speed and a reduced accident rate than those observed while driving a vehicle without ICWS audio signal. Furthermore, Path Analysis showed that the ICWS had an indirect effect on accident rate reduction through improved driving performance. The location of intersection accident had both direct and indirect effects on the accident rate. The number of driving days per week had a direct effect on accident rate reduction.     

The driving anger expression inventory: a measure of how people express their anger on the road

Four ways people express their anger when driving were identified. Verbal Aggressive Expression (alpha=0.88) assesses verbally aggressive expression of anger (e.g., yelling or cursing at another driver); Personal Physical Aggressive Expression (alpha=0.81), the ways the person uses him/herself to express anger (e.g., trying to get out and tell off or have a physical fight with another driver); Use of the Vehicle to Express Anger (alpha=0.86), the ways the person uses his/her vehicle to express anger (e.g., flashing lights at or cutting another driver off in anger); and Adaptive/Constructive Expression (alpha=0.90), the ways the person copes positively with anger (e.g., focuses on safe driving or tries to relax). Aggressive forms can be summed into Total Aggressive Expression Index (alpha=0.90). Aggressive forms of expression correlated positively with each other (rs=0.39-0.48), but were uncorrelated or correlated negatively with adaptive/constructive expression (rs=-0.02 to -0.22). Aggressive forms of anger expression correlated positively with driving-related anger, aggression, and risky behavior; adaptive/constructive expression tended to correlate negatively with these variables. Differences in the strengths of correlations and regression analyses supported discriminant and incremental validity and suggested forms of anger expression contributed differentially to understanding driving-related behaviors. Theoretical and treatment implications were explored.     

Evaluating the impact of adaptive signal control technology on driver stress and behavior using real-world experimental data

While the operational and crash reduction benefits of adaptive signal control technology (ASCT) have long been investigated, the impact of this technology on driver behavior and stress is still uncertain. This study evaluated the impact of ASCT on driver behavior and stress in a real-world environment. Participants travelled through two arterial corridors, one equipped with ASCT and the other having traditional time-of-day coordinated signals. Driver stress was measured using a heart rate detector and a perceived stress scale while driver behavior was examined using vehicular trajectory data. Overall, driving behavior improved on the ASCT as compared to the non-ASCT corridor, as indicated by higher speeds and a fewer number of stops on the ASCT corridor relative to the non-ASCT corridor. Repeated measures ANOVA showed a statistically significant reduction in driver heart rate by −10 beats per minute over the ASCT corridor. A similar trend was observed for drivers’ perceived stress, analyzed by Wilcoxon sign ranked test. Driving behavior also showed significant improvement with ASCT presence, and speed was found to be negatively correlated with stress. Furthermore, the participants’ speed was controlled by the two systems i.e. ASCT and non-ASCT as expected. This study provides a significant proof of concept that ASCT can create positive improvements in driver stress and behavior that can be further investigated in the future.     

The influence of attention allocation and age on intersection accidents

Many severe accidents occur in urban areas. As part of the research project UR:BAN, this study investigated the causes of driver errors (e.g., inadequate attention allocation) in urban areas when turning left at intersections. As intersection accidents are especially difficult for older drivers, differences between older and younger drivers were examined as well. In a first step, accident protocols of left turn crashes with pedestrians and bicyclists were analysed in detail, since they are the most dangerous ones. Characteristics of the oncoming traffic and the location of crossing bicyclists and pedestrians were identified as possible causes. Accordingly, critical scenarios were implemented in a static driving simulator, varying the characteristics of the oncoming traffic, the direction and location of crossing vulnerable road users. These factors were examined in a within-subject design, with two different aged groups of participants (12 aged 20–35 y, 12 aged 65+ y; between-subjects factor).The results revealed that the presence of the oncoming traffic, which was assumed to capture the drivers’ attention, did not lead to more accidents with vulnerable road users. However, this may be because many drivers waited until the oncoming traffic had passed. Unexpectedly, older drivers had fewer accidents. This may be explained by the more cautious behaviour of older drivers, who drove significantly slower and waited significantly longer at the stop line before turning. Further analyses showed that a more cautious behaviour, independently of the age, predicted accident avoidance better than attention allocation. From these results, warning systems for younger and older drivers, especially for those not driving cautious, need to be developed. This idea will be tested in future studies introducing different warning concepts.     

Using physiological and behavioral measurements in a picture-based road hazard perception experiment to classify risky and safe drivers

Every year, a considerable number of people got injured or even lost their lives in road traffic accidents. To decrease the number of fatalities and injuries, researchers are seeking methods to identify and restrain drivers before the happening of actual traffic accidents, who possess dangerous driving behaviors and may cause road traffic accidents. Such methods are usually exploited to decide drivers’ fitness to drive—an indicator to describe whether they are fit for driving. The aim of this study is to measure drivers’ physiological and behavioral responses to road hazards and to extract features from measurements for further classification of risky and safe drivers. 42 drivers participated in a picture-based road hazard perception experiment, where electroencephalography (EEG), electrodermal activity (EDA), behavioral responses to road hazards, multidimensional driving style inventory (MDSI) questionnaire, and demographic information were recorded. Results indicated that 5 specific physiological features regarding to road hazard perception showed significant differences between risky and safe drivers. Subsequently, participants were classified into risky or safe drivers group by applying only the 5 features. 81.82% and 77.78% accuracy of classification were attained for risky and safe drivers, respectively. It was evidenced that using physiological and behavioral responses to evaluate drivers’ road hazard perception might be utilized as a tool to measure drivers’ fitness to drive. For further studies, improvements to future experiment design were discussed.     

Keep on cruising: Changes in lifestyle and driving style among male drivers between the age of 18 and 23

Despite recent improvements in general road safety levels, young male drivers in most western countries continue to be overrepresented in road traffic accidents. Lifestyle related motivational factors are a key element in the young male driver problem. Based on 379 posted questionnaires completed by the same male drivers at the age of 18 and again at the age of 23, this study examined changes in the relationship between lifestyle and driving style over a 5 year period. A number of changes in car use, driving style and engagement in different leisure time activities were found. Cruising was related to an extrovert social life as well as problem behaviours such as drink driving. At the age of 18 cruising was a part of the normal social life of the majority of the participants. However, while most drivers reduced their level of cruising as well as related problem behaviour over time, a smaller group still showed a similar life style at the age of 23. The study confirmed the importance of lifestyle related motivational factors for driving behaviour among young drivers.     

Driver responses to motorcycle and lead vehicle braking events: The effects of motorcycling experience and novice versus experienced drivers

In many countries, motorcyclists are over-represented in traffic collision fatalities and injuries compared to vehicle registrations. Why drivers may violate the right-of-way of motorcyclists traveling as lead vehicles in front of drivers is empirically examined in two studies that were conducted with a moderate-fidelity driving simulator. The purpose of the first study was to determine if drivers, who also held a motorcycle license (N = 16), drove cars differently than regular drivers (N = 16) around motorcycles. The two groups did not differ on responses to motorcycling braking events, which was consistent with previous research on car following. The second study compared the driving performance of sixteen novice teenage drivers (M = 16.2 years of age) to 15 experienced drivers (M = 32.9) over the span of six monthly simulator sessions. Novice drivers’ perception response times (PRT) to the braking events were significantly longer than those of the experienced drivers. PRTs to motorcycle and lead vehicle braking events decreased over sessions. For all participants, PRTs to the motorcycle events were longer than to the car events. The implications of these results for motorcyclists and drivers with different levels of experience are discussed.     

Stay calm! Regulating emotional responses by implementation intentions: Assessing the impact on physiological and subjective arousal

Implementation intention (IMP) has recently been highlighted as an effective emotion regulatory strategy. Most studies examining the effectiveness of IMPs to regulate emotion have relied on self-report measures of emotional change. In two studies we employed electrodermal activity (EDA) and heart rate (HR) in addition to arousal ratings (AR) to assess the impact of an IMP on emotional responses. In Study 1, 60 participants viewed neutral and two types of negative pictures (weapon vs. non-weapon) under the IMP “If I see a weapon, then I will stay calm and relaxed!” or no self-regulatory instructions (Control). In Study 2, additionally to the Control and IMP conditions, participants completed the picture rating task either under goal intention (GI) to stay calm and relaxed or warning instructions highlighting that some pictures contain weapons. In both studies, participants showed lower EDA, reduced HR deceleration and lower AR to the weapon pictures compared to the non-weapon pictures. In Study 2, the IMP was associated with lower EDA compared to the GI condition for the weapon pictures, but not compared to the weapon pictures in the Warning condition. ARs were lower for IMP compared to GI and Warning conditions for the weapon pictures.     

Adaptation of the safe driving climate among friends scale in Chinese drivers and its associations with risky driving behaviours

The present study aimed to adapt the Safe Driving Climate among Friends Scale (SDCaF) to Chinese drivers and to examine its reliability and validity. Three hundred and sixty drivers aged from 18 to 24 years old were asked to complete the SDCaF and the Risky Driving Behaviour Scale. A confirmatory factor analysis (n = 360) was conducted to examine the factorial structure of the SDCaF. The validity of the scale was then evaluated by examining the associations between the SDCaF factors, risky driving behaviours and traffic violations. The CFA results showed that the model fit of the Chinese version of the scale (SDCaF-C) was acceptable. Second, the SDCaF-C factors were weakly or moderately correlated with speeding, self-assertiveness and rule violations. Third, significant gender differences were found for the variables of friend pressure and communication, with male drivers scoring higher than female drivers. Moreover, drivers who had traffic violations in the past year scored higher on friend pressure and lower on both communication and shared commitment to safe driving compared to those who had not had traffic violations. The findings supported the psychological properties of the SDCaF-C and highlighted the importance of concerning the effects of safe diving climate among friends on young drivers’ risky driving behaviours.     

Differential effects of driver sleepiness and sleep inertia on driving behavior

ObjectivesDriver sleepiness is one of the major safety issues in conventional driving and sleep inertia emerges as a driver state in automated driving. The aim of the present study was to assess the differential impacts of sleepiness and sleep inertia on driving behavior.Method61 participants completed a 10-min manual driving task during an otherwise automated drive. They completed the task (a) under an alert state, (b) under a sleepy state, and (c) after EEG-confirmed sleep. Driving performance was assessed with the parameters lane-keeping, speed choice, and speed-keeping. The eye-blink-based sleepiness measure PERCLOS (the proportion of time with eyes closed) was compared for the three driver states.ResultsLane- and speed-keeping performance were impaired under the sleepy state and after sleep, relative to the alert state. After sleep, lane-keeping behavior recovered rapidly and speed-keeping recovered by trend. Under the sleepy state, performance deteriorated. After sleep, the mean speed was lower than in the sleepy state and in the alert state. PERCLOS was increased after sleep and under the sleepy state, relative to the alert state.ConclusionsAlthough sleep inertia had detrimental effects on driving parameters similar to sleepiness, this effect rapidly vanished. Hence, while brief naps might be suitable to restore alertness in general, the minimal time needed to regain full capacity after napping should be a focus of future research.     

Effects of a driver assistance system with foresighted deceleration control on the driving performance of elderly and younger drivers

It is imperative to enhance the safety of elderly individuals on the roads to ensure the quality of their daily life. Near-miss incidents or accidents at blind intersections often result from a conflict between the behaviors of the driver and of other road users (pedestrians and cyclists). The failure to search for potential conflict in the context of blind intersections is a concern pertaining to road safety. The proposed assistance system performs a proactive braking intervention to achieve a referenced velocity in uncertain situations, such as one in which an unobserved pedestrian might initiate a road crossing. The proactive braking intervention attempts to manage the potential risk of crashing with respect to covert hazards. Because an automated system may impair a human’s ability to perceive and respond to hazardous situations while driving, this study was designed to examine the effects of proactive braking intervention and visual support cues on elderly and younger drivers’ ability to respond to information about potentially hazardous situations. We conducted a public-road driving experiment involving 108 elderly and younger drivers from two non-overlapping age groups. It was observed that the vehicle slowdown realized through the proactive braking intervention enabled the drivers to perform safety confirmation near blind spots and caused them to be more sensitive to and wary of potential hazards. This approach could be effective not only for elderly drivers, but also for young or inexperienced ones.