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Fatal Distraction? A Comparison of the Cell-phone Driver and the Drunk Driver
Get PDFWe used a high-fidelity driving simulator to compare the performance of cell-phone drivers with drivers who were legally intoxicated from ethanol. When drivers were conversing on either a hand-held or hands-free cell-phone, their reactions were sluggish and they attempted to compensate by driving slower and increasing the following distance from the vehicle immediately in front of them. By contrast, when drivers were legally intoxicated they exhibited a more aggressive driving style, following closer to the vehicle immediately in front of them and applying more force while braking. When controlling for driving difficulty and time on task, cell-phone drivers exhibited greater impairment than intoxicated drivers
Mental Workload as a Function of Traffic Density: Comparison of Physiological, Behavioral, and Subjective Indices
Get PDFHigh traffic density can be expected to increase the attentional processing requirements of driving. Establishing methods of assessing the differential demands placed on drivers by environmental variables has been the focus of a recent series of investigations. Results of an initial examination of the impact of traffic density on mental workload are reported here. The current investigation utilizes an array of methodological assessment techniques and compares the sensitivity of each to changes in attentional processing requirements as a function of driving task demand. Analogous versions of a visual and auditory sensory detection task were developed and used in a dual task paradigm involving simulated driving. P300 amplitude, though in the predicted direction, failed to distinguish between increased task demands resulting from increases in traffic density. Response time and accuracy to the detection task in both visual and auditory modalities demonstrated significant processing decrements as a function of increased traffic density. Subjective workload ratings obtained from the NASA TLX did not distinguish between driving task difficulty, but indicated that performing the visual detection task in combination with driving was perceived as more difficult than performing the concurrent auditory task. Implications of these results for modeling differential aspects of mental workload and for establishing workload assessment techniques for surface transportation environments are discussed
Reliability of a Road Test After Stroke
Get PDFBackground: Despite physical, perceptual and cognitive impairments, amongst others, which might affect driving after stroke, some patients have demonstrated the ability to resume safe driving. Such patients are identified following strictly administered predriving evaluations. The road test is generally acclaimed to be the most valid test of driving performance. Aim: The purpose of this study was to determine the reliability of the road test when performed by stroke patients in Belgium. Method: This was a prospective study of a predriving evaluation at the Belgian Road Safety Institute. Thirty subjects with sequelae of stroke were included. Subjects were accompanied and evaluated during the road test by one of two assessors (A or B) from the road safety institute in an automatic car fitted with a video camera for recording driving performance. Inter-rater reliability was evaluated by comparing results from (1) real-life performance and video recording and (2) between-video judgements. Results: Most sub-items of the road test showed >80% scoring agreement between the various evaluations. Intraclass correlation coefficient (ICC) of the items varied from -0.08 to 1.0. ICC of the overall performance was 0.62 when real-life scores were compared with video evaluations and 0.80 in video versus video comparison. Conclusion: Driving is important for optimal participation in daily and social activities. The reliability of assessing overall performance of the on-road test is moderately high and better when assessed using same evidence. Yet, the reliability of some items needs further attention
The Evolution of Autonomic Space as a Method of Mental Workload Assessment for Driving
Get PDFBecause heart rate lacks diagnosticity, an autonomic space approach for the assessment of mental workload has been proposed. In addition to increasing the capability to identify differences between tasks, the autonomic space approach can be used to make better inferences about the psychological processes involved. In this paper, the approach and its application to a simulated driving task are discussed, as well as suggestions for future research and its development
Truck Driver Training Using Simulation in England
Get PDFThe UK Department for Transport, on behalf of the Road Haulage Modernisation Fund, has established a research programme to determine the potential role of synthetic training in both ab initio license acquisition and also skills development in experienced drivers. TRL and EADS Dornier are commissioning an advanced full-motion-base truck simulator and developing bespoke courseware. The potential benefit of the system will be evaluated through a structured programme of training over 600 drivers. This paper reviews the current legislative framework in the UK and the European Union and discusses potential changes that will impact the training market. The paper then discusses the outline of the research programme and the technical capability of the system being develope
Visual Attention in Stroke Patients Returning to Driving
Get PDFThe UK along with many European countries lacks a standardised test to objectively test visual attentional deficits in drivers of vehicles, particularly following stroke injury. Detecting motion components in the visual scene may be the first indication of an impending collision, however, this is often overlooked in current assessment procedures. The series of experiments presented here used a semi-immersive virtual reality paradigm and eye gaze monitoring technology, to identify deficits in peripheral processing and extend the concept of useful field of view (UFOV) (Ball et al. 1988; 1993). We used displays that tested peripheral attention with brief (90ms) episodes of relative motion, changing size, luminosity and colour. Participants were presented with different sets of stimuli on a large video screen at 10°, 20°, and 30° eccentricities and used a natural gaze response to look to the cued location. Gaze response was monitored using an ASL 504 eye movement tracking system, and the dependant measure was accuracy of saccade to the eccentric target. Six stroke participants (mean age = 61.16) were tested, and their results compared against previously gathered data for the same experiments from three healthy aging groups of drivers (Young: N=21, mean age = 25.29, Middle aged: N=20, mean age = 50.25, and Elderly: N=20, mean age = 70.50). The systematic decrease in performance with increasing age that was previously found for the healthy aging participants (p< 0.001) was also found in the stroke group, who performed worse than the healthy aging groups in the same tasks (p< 0.001). The results underpin our previous finding of deficits in processing basic components of visual control that go beyond current UFOV tests. These current results highlight the compounding effects of stroke injury on the ability of attention to be captured by motion components that may be the first and only indication of an impending collision event. We discuss the implications of treating stroke patients as though they belong to a homogenous group when assessing suitability to return to driving; our results indicate that they clearly do not. Younger stroke drivers made recoveries that placed their performance alongside that of their age-matched healthy controls, unlike older stroke patients who remained more impaired than their age-matched healthy controls. We conclude that assessment of visual attention as it relates to moving objects in a visually cluttered environment should be part of any assessment criteria for measuring fitness to drive in stroke patients making a return to driving
Risk of Fatal Rear-End Collisions: Is There More to It Than Attention?
Get PDFRear-end collisions predominantly occur in the daytime under clear, unobstructed viewing conditions and usually involve a lead vehicle that is stopped at the time of collision. These facts suggest that driver inattention plays a significant causal role in rear-end collisions, and mitigation efforts have therefore focused largely on development of warning technologies to alert drivers of an impending crash. However, we note that this pattern of crash data should not lead to the conclusion that drivers have special difficulty avoiding rear-end collisions in broad daylight. Nor should it be concluded that other “environmental” factors do not influence driving behavior to increase rear-end crash risk. Crash frequency is determined both by the inherent risk in the driving task and by the frequency of driver exposure to conditions in which a crash is possible. When exposure level is equated across conditions which differ in ambient light level, we find that rear-end collisions appear to be more than twice as likely in darkness than in daylight
Commuter Behavioral Model for the Pilot Program of an Electronic Toll System on Korea Express Highways
Get PDFIn recent years, congestion pricing has gained popularity as a method for managing peak-period congestion on major roads in urban areas. Intelligent Transportation Systems (ITS) technology has resulted in an electronic toll collection (ETC) system called “Hi-Pass,” which is operated by the Korea Highway Cooperation for the pilot program. The limited sections of highway involved in the program have gained good approval ratings from motorists. In this research, the Korean highway toll system was analyzed with respect to the brief legal history of the toll road, collection method and levels. In addition, the electronic toll collection policy for foreign countries including France, Norway, and Italy are investigated. The toll system of each country is clearly differentiated with regard to the institution, regulation and the country’s economy. In the review of the pilot ETC program “Hi-pass” system in Korea, several important factors were found. First, a more concrete marketing strategy for ETC users will needed to encourage continued usage. In particular, frequent users and higher-income users adopted the ETC system more easily than others did. Second, in order to encourage the non-user to try the ETC system, the costs of on-board units must be kept reasonably low (about $50), and aggressive discounts (about 3-5% compared to the current 1%) are needed
Evaluation of a Low-Cost, PC-Based Driving Simulator to Assess Persons with Cognitive Impairments Due to Brain Injury
Get PDFBrain injury due to accident or stroke frequently results in cognitive impairment, reducing an individual’s ability to judge driving situations accurately. Rehabilitation professionals typically use a combination of clinical and on-road tests to determine whether an individual is safe to drive. Weighing the safety of the community, the candidate, and the driving evaluator, these on-road tests are often conducted under road, traffic and weather conditions less demanding than those that a driver might face in the “real world,” and thus may offer less than complete information regarding the candidate’s responses to such real-world driving challenges. Indeed, individuals with mild cognitive deficits may perform adequately under such testing conditions but unsafely when driving challenges increase. Complicating this situation further, those with mild to moderate acquired cognitive impairments may be largely unaware of their own limitations, and thus more intolerant of perceived delays or challenges to their desire to drive again. Although continuing advances have improved performance and fidelity while significantly reducing costs, most interactive driving simulators remain too expensive for widespread clinical application. In a project funded by the National Center for Medical Rehabilitation Research, National Institutes of Health, we sought to determine, on a pilot basis, whether a low-cost, PC-based driving simulator could provide clinicians with information useful to their efforts to assess the safe ability to drive of individuals with cognitive impairments. We developed two comprehensive simulator-based driving scenarios, one quite basic and one more challenging, and pilot-tested them on ten subjects – five with moderate cognitive impairments, and five age and sex matched-controls without impairment. The “simple” scenario was developed to match the essential demands of the first half of an existing on-road driving evaluation; the “complex” scenario was based on the second half of the on-road evaluation into which more demanding, but still common, driving challenges were integrated. Road types, lane widths, pavement markings, traffic signals, horizontal and vertical curvature, and the proximal built environment were all created in simulation to provide a convincing generic representation of the on-road test. Challenges incorporated into the “complex” phase of the scenario, which were absent from the “simple” phase, included traffic events such as: cross-traffic failing to stop at a STOP sign; pedestrians crossing the driver’s path; vehicles suddenly pulling out in front of the subject from the road shoulder; opposing thru traffic appearing suddenly from behind slower moving vehicles as the subject attempted to turn left; slower moving lead vehicles causing passing decisions; traffic streams forcing gap acceptance decisions; etc. Results from the simulator were compared to results from the on-road evaluation. In addition, data gathered from subject exit interviews was used to judge simulator verisimilitude and efficacy in changing self-awareness of deficit. Because the cognitive impairments associated with brain injury often reduce the individual’s awareness of his or her own limitations, we looked at evidence that performance on the simulator could contribute to an individual’s own understanding of his or her driving strengths and weaknesses. The results of the pilot study will lead to an enhancement of simulator capabilities, and to a comprehensive clinical trial at multiple sites. This paper will present the findings of this pilot investigation and an overview of the expanded clinical study
Performance on Cue Recognition and Evasive Action Skills as Predictors of Effective Driving in College-Age Drivers
Get PDFTwo experiments compared self-reported driving effectiveness oflicensed drivers (mean age 19 years) to their performance on two simulateddriving tasks. For both experiments, drivers first completed a driving historyquestionnaire. In Experiment 1, they then performed Cue Recognition, whichuses stationary line drawings of vehicles as stimuli and requires a turning orbraking response to an appropriate stimulus. Males responded faster than females,especially for the most complex choice responses, and reported more tickets.Drivers reporting no tickets responded slower than those reporting at least oneticket, and they reported fewer accidents. In Experiment 2, drivers also performedEvasive Action Skills, which uses more realistic recorded driving scenarios inwhich the appearance of a hazard is the imperative stimulus that commands theappropriate turn or brake response. Number of errors on Evasive Action Skillscorrelated significantly with number of self-reported accidents. Response timeson Cue Recognition and Evasive Action Skills were correlated, but there was norelation between response times on Cue Recognition and errors on EvasiveAction Skills. However, a comparison of the 10 fastest and 10 slowest drivers onCue Recognition showed that the fastest responders committed significantly moreerrors on Evasive Action Skills than did the slowest responders. The data in bothexperiments reflect a speed-accuracy tradeoff