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Training of Driving-Related Attentional Performance After Stroke Using a Driving Simulator
Get PDFThe objective of this study was to determine the effect of simulatorbased driving training on attentional performance after stroke. A further analysis of data was conducted from a randomized controlled trial in which the effect of simulator training and cognitive paper and pencil training to improve driving were compared. Performance in divided attention tasks before, during and after 15 hours of simulator-based training of general driving skills in 33 experimental participants were evaluated. Performance in divided attention tasks was assessed during navigation of a 5-km scenario with the divided attention tasks as the only event to respond to and another 13.5-km scenario that contained a good mixture of regular day to day traffic situations. There were significant improvements in mean response time to the divided attention tasks and time to complete the 5-km scenario. Significant decrease in mean response time, number of missed responses, collisions, pedestrians hit, total faults and run time and increase in number of correct responses were found in the 13.5-km scenario. Further analyses showed most improvements in the simulator assessments occurred between preand mid-training. Simulator-based training of driving skills positively impacted attentional performance. Findings in this study suggest that 10 hours of simulatorbased driving training after stroke is sufficient to realize meaningful benefits
Perceptual-Motor Control Strategies for Left-Turn Execution
Get PDFThe purpose of the present study was to investigate the perceptualmotor strategies used by drivers during left-turn execution as a means of identifying potential causes of such accidents and to inform the design of left-turn warnings. Twenty-one participants executed a series of left turns in a driving simulator. The initial distance(D) and time to intersection(TTI) of an oncoming vehicle were varied orthogonally to present drivers with a range of different safety margins. The initial distance values ranged from 50 to 150m, and the TTI values ranged between 4 to 12 sec. Accidents occurred on roughly 3% of the trials, with large individual differences in performance. The most common conditions for accidents to occur involved a large value of D(>=100) and a medium-short value of TTI(<=6). The timing of left-turn initiation was significantly affected by both the TTI and the distance of the oncoming vehicle. On average, left turns were initiated at a shorter TTI when the distance was large. We conclude that since there were several instances in which drivers used the unsafe strategy of basing their decision to turn on the distance of the oncoming vehicle, a left-turn warning that is based on temporal information alone (e.g., Nowakowski, 2006) will likely be unreliable, because the decision to turn is not solely based on temporal information
Crashing Under Pressure: An Examination of Older Driver’s Reactions to Simulated Challenging Road Events
No full textThe driving reactions of 20 older and 20 young adults to two surprising events with varying levels of complexity was examined. Cognitive measures of workload, divided attention and reaction time were also collected. The results revealed that older adults experienced more difficulties when confronted with a surprising event that was more complex and required a rapid reaction. Crash risk was found to be associated with self-reported cognitive workload and divided attention (UFOV) results. The obtained results are in line with current cognitive mode ls of the aging driver
Diabetes and Motor Vehicle Crashes: A Systematic Evidence-Based Review and Meta-Analysis
Get PDFThe primary objective of this systematic review was to address the question, “Are drivers with diabetes mellitus at greater risk for a motor vehicle crash than comparable drivers without the disease?” and secondarily, to address the question, “Are insulin-treated diabetics at higher risk for crash?” Our searches identified 16 articles that addressed these questions. An assessment of study quality of the included studies found them to be in the low-to-moderate range. While attempts were made to control for differences in the characteristics of individuals that may confound the relationship between diabetes and crash risk in all included studies, most failed to control for exposure. A random-effects metaanalysis found that individuals with diabetes have a 19% increased risk for a motor vehicle crash when compared to similar individuals without diabetes. We found no compelling evidence to suggest that insulin-treated individuals are at higher risk for motor vehicle crash than individuals with diabetes not being treated with insulin. We discuss the implications of these findings
Formative Evaluation of Engineering Designs Using Driver Performance in a Immersive Driving Simulator
Get PDFThe systems engineering approach employs iterative evaluation of human factors issues throughout the system design process. Formative evaluation and refinement of user interfaces promotes cost savings by continuously validating design concepts and defining needs for improving the designs at the earliest possible point in the engineering process. Testing may use varying levels of prototypes of the system or simulations of its responses and user interfaces. While human factors evaluation frequently uses paper or foam board mockups, immersive driving simulators enhance the process by incorporating realistic road geometries and traffic flows and by requiring driver perception, decision making, and control actions in realistic scenarios and timelines. Three studies conducted in the Western Transportation Institute driving simulation laboratory are summarized. These used an immersive driving simulator to evaluate drivers’ responses to (1) Intelligent Transportation System (ITS) deployments on a rural highway, (2) the user interface to a lane departure warning system, and (3) a proprietary cooperative warning system for installation on the exterior of vehicles
Aging and the Effects of Conversation with a Passenger or a Caller on Simulated Driving Performance
Get PDFA total of 96 pairs of older and younger drivers participated in a study assessing the effects of conversation on the driving performance of older and younger drivers in a simulated city environment. These effects were investigated while drivers conversed with an in-vehicle passenger or an outside-vehicle caller. All of the passengers completed three separate, counterbalanced blocks of tasks that consisted of two single-task blocks (driving only and conversing only) and one dual-task block (driving and conversing). The results showed greater variability in velocity, lane keeping and steering control under single-task than under dual-task conditions. Drivers also showed greater average velocity and greater deviation from the center of the lane under single-task than under dualtask conditions. However, when crossing an intersection, a task requiring greater attentional resources, drivers exhibited a cost due to the dual task. Our data are consistent with the literature, which suggests that a secondary task may aid in the performance of a routinized task but may also impose costs if the primary task requires significant attentional resources. Older drivers exhibited greater variability in velocity, stayed closer to the center of the lane, and waited longer to cross intersections than their younger counterparts, suggesting that they compensate for their declining perceptual and cognitive abilities through changes in driving behavior. Drivers exhibited greater variability in steering under singletask conditions when talking to an outside-vehicle caller, and older drivers showed greater variability in velocity when conversing with an outside-vehicle caller
Driving Simulator Performance Across the Lifespan: A Preliminary Study
Get PDFOBJECTIVES Normal aging is associated with decline in abilities that may put an individual at increased riskfor a crash. Older individuals may have slowed processing speed and motor responses, a reduceduseful field of view (Ball et al., 1988), and greater difficulty with mental rotation (Armstrong etal., 1998). Although collision rates increase with age (Transportation Research Board, 1988), ithas been argued that specific age-related functional impairments, and not age itself, put one atrisk (Ball & Owsley, 2003). The goal of this study was to examine the relationship betweenaging and performance on driving simulations assessing specific components of driving—accident avoidance, divided attention, and navigation—and the degree to which they predict onroaddriving performance.METHODSForty control drivers (age 22 to 84; 70 yo, n = 13)completed 3 simulations and an on-road driving evaluation. Exclusion criteria includedneurologic confounds, substance use and psychiatric disorders, as well as abnormalneuropsychological performance (based upon demographically-corrected norms). Thesimulations were presented on a Pentium III PC computer using a 17” monitor at 1280 x 1024resolution, and running STISIM Drive version 2.0 software (Systems Technology, Inc.;Hawthorne, CA). Hardware included a steering wheel, turn signal, and brake/accelerator pedals.The simulations consisted of 1) Advanced Routine and Emergency Driving (ARED), a 15-minute route simulating city/country driving, in which drivers must obey traffic signs, pass cars,and respond to high-risk crash scenarios; 2) Virtual City (VC), in which drivers must navigate toand from a location in a 5 x 5 block simulated city, and 3) Divided Attention, in which driversare to maintain a constant speed and lane position while responding to divided attention tasks inthe corner of the monitor. Participants also completed a 35-minute on-road assessment. Lastly,participants were assessed on a battery of neuropsychological tests. Earlier versions of thesimulations were predictive of on-road driving performance in an HIV-infected cohort (Marcotteet al., 2004). RESULTSThe three groups performed similarly on ARED (crashes, speeding tickets), as well as on the VCtask when the map was oriented to the same direction as the participant. On the other hand, olderparticipants had significantly more difficulty navigating when their orientation on the map wasreversed (e.g., the 70 years old groups took approximately 7.5 blocks). The three groups performedsimilarly with respect to lane deviation on the Divided Attention task, but the older groups hadincreased variability in speed maintenance, and the oldest group failed to respond to a greaternumber of divided attention stimuli ( 70 yo = 3.6 (2.7)).Although only one participant failed the on-road drive (50-70 yo), the percent of driversconsidered marginal or worse increased with age (7% vs. 25% vs. 55%). In a logistic regression,the simulator variables that best discriminated safe vs. marginal on-road came from the DividedAttention task: the number of missed stimuli and speed deviation, both of which require an intactuseful field of view and the shifting of gaze away from the roadway. Age did not enter into amodel that included these variables.CONCLUSIONSIn this study of normal, healthy controls, older participants drove similarly to young-to-middleaged participants on a simulation that most closely approximated real driving. Consistent withcognitive declines seen in normal aging, older participants had greater difficulty on a taskrequiring navigating when map orientation was reversed (perhaps indicative of impairedegocentric spatial abilities), as well as on a measure of driving-related divided attention, witholder participants appearing to allocate more attention to the roadway at the cost of attending andresponding to peripheral cues. Although older drivers had more difficulty during the on-road test,these difficulties were a function of deficits in the ability to divide attention efficiently, ratherthan aging per se.REFERENCESArmstrong, C.L., & Cloud, B. (1998). The emergence of spatial rotation deficits in dementia andnormal aging. Neuropsychology, 12(2), 208-217.Ball, K.K., Beard, B.L., Roenker, D.L., Miller, R.L., & Griggs, D.S. (1988). Age and visualsearch: Expanding the useful field of view. J Opt Soc Am A, 5(12), 2210-2219.Ball, K., & Owsley, C. (2003). Driving competence: It's not a matter of age. J Am Geriatr Soc,51(10), 1499-1501.Marcotte, T.D., Wolfson, T., Rosenthal, T.J., Heaton, R.K., Gonzalez, R., Ellis, R.J., et al.(2004). A multimodal assessment of driving performance in HIV infection. Neurology, 63(8),1417-1422.Transportation Research Board. (1988). Transportation in an Aging Society, Vol 1. Washington,D.C.: National Research Council
Effect of a Side Collision-Avoidance Signal on Simulated Driving with a Navigation System
Get PDFEffects of a side collision-avoidance system (SCAS) signal on driving behavior were examined in an environment in which a nagivation signal was also used. Sixteen undergraduate students participated in this study, and a computerbased STISIM driving simulator was used in the project. Subjects were asked to respond to two signals, a visually displayed directional signal generated by a simulated navigation system (NAS) and a monaural auditory tone from a simulated SCAS presented after a NAS signal. Subjects were instructed that the SCAS signal conveyed directional information about an impending threat (the location of the danger from which they were to turn, or the escape direction toward which they were to turn). Contrary to previous findings in a non-driving environment (Wang et al., 2003), response time (RT) was significantly shorter for the group in which the location of the SCAS signal was spatially compatible with the location of the danger than for the group in which the SCAS signal location was incompatible with the location of the danger. Mean RT was not significantly shorter when the direction of the NAS signal and the location of the SCAS signal corresponded than when they did not. Given that subjects tended to withhold responding until they perceived the encroaching car, the benefit of a SCAS may be to direct a driver’s attention in the direction of an impending threat before the driver would ordinarily detect it
Evaluation of Fatigue Management Technologies Using Weighted Feature Matrix Method
No full textOperator fatigue is one of the most prevalent root causes of accidents,both on the highway and in workplaces where heavy equipment is used and 12-hour shifts are employed, such as in the mining industry. In response to thisconcern, a growing number of Fatigue Management Technologies (FMT) arebecoming available to help maintain operator alertness and performance levels bydetecting operator fatigue and interfacing with the operator and/or supervisor toprevent accidents and incidents (Williamson et al., 2005, Barr et al., 2005). Inlight of the numerous competing technologies, the research community, as well asindustry, could benefit from the flexible evaluation tool proposed here. It willassist industries as a whole, and corporations more specifically, in identifying thebest FMT solutions for different work and/or driving situations. This project wasspecifically focused on the needs of operators of heavy equipment in the miningindustry, but could also be of value to other like industries where shift work isnecessary and maintaining high levels of alertness are crucial for ensuringworkplace safety and productivity
Indirect Clinical Evidence of Driver Inattention as a Cause of Crashes
Get PDFA recent report from the 100-Car Study identified driver inattention as a significant risk factor for involvement in crashes or near-crashes. If in fact inattention is a cause of crashes, it should be possible to find at least indirect evidence of it by reconstructing actual crashes. This paper describes reconstruction of two rear-ending crashes on an urban freeway, one left-turn cross-path crash on a suburban arterial, and one vehicle/pedestrian collision. Bayesian reconstruction methods were used to estimate driver reaction times, and these were then compared to reaction time measures from the literature. The working hypothesis was that atypically long reaction times on the part of the colliding drivers would provide indirect evidence for driver inattention. It turned out that an atypically long reaction time was shown by only one of the four colliding drivers, but that other indications of inattention were found in two other crashes