Matthew C. Crisler

Simulator sickness during driving simulation studies.

While driving simulators are a valuable tool for assessing multiple dimensions of driving performance under relatively safe conditions, researchers and practitioners must be prepared for participants that suffer from simulator sickness. This paper describes multiple theories of motion sickness and presents a method for assessing and reacting to simulator sickness symptoms. Results showed that this method identified individuals who were unable to complete a driving simulator study due to simulator sickness with greater than 90% accuracy and that older participants had a greater likelihood of simulator sickness than younger participants. Possible explanations for increased symptoms experienced by older participants are discussed as well as implications for research ethics and simulator sickness prevention.

Effect of Wireless Communication and Entertainment Devices on Simulated Driving Performance

An analysis of the effect of wireless telephone communication using text and voice modalities as well as an Apple iPod on lane keeping, speed, speed variability, lateral speed, and lane position variability was conducted with a driving simulator. Participants (young adult licensed drivers) drove in an unusually curvy simulated driving environment while using wireless devices, controlling an iPod, and participating in conversations and word games. As expected on the basis of previous research, lane-keeping performance was robust for voice communication tasks; however, the text messaging and iPod tasks that required significant manual manipulation of the device resulted in significant decrements in lane-keeping performance. In addition, all wireless communication tasks and the iPod task resulted in significant increases in speed variability throughout the driving scenario. Lateral speed increases occurred for all wireless communication tasks other than the cellular phone conversation as well as the iPod task. Increases in lane position variability were observed for the text messaging conditions. In addition to establishing the dramatic performance decrement caused by text messaging tasks, this experiment suggests that driving performance may be affected by distraction in ways not captured by lane-keeping measures alone and explores potential alternative measures of driving performance that may be useful for identifying and quantifying the effects of distracted driving.

Speed choice and driving performance in simulated foggy conditions

Driving in fog is a potentially dangerous activity that has been investigated in a number of different ways; however, most have focused on identifying the underlying perceptual changes that result in an inability to perceive speed of vehicle motion. Although the previous research has identified the perceptual changes associated with driving in fog and shows that people are highly likely to perceive their speed to be higher than it actually is, these research studies have not investigated driving behavior when drivers are allowed to maintain speed as they feel appropriate and make use of the vehicles speedometer. In addition, much of the existing research focuses on speed perception and presents a limited view of other driving performance metrics in terms of lane keeping and event detection. The current study addresses these issues utilizing a driving simulator-based method where fog is simulated as a distance dependent contrast reduction while having participants drive at speeds they feel are appropriate. A number of different instructions and speed feedback mechanisms were tested in order to determine how drivers react when driving in varying levels of fog. Results also include lane keeping measures in order to assess whether drivers are willing to drive at speeds where their lane keeping performance is degraded due to the reduced visibility. Results indicate that, in general, drivers do not tend to slow down significantly until visibility distance is drastically reduced by fog; however, lane keeping ability is maintained throughout most of the range of visibility distances. Lane keeping ability was reduced only when fog results in visibility distances <30 m. Overall, the current study shows that drivers are willing and able to maintain vehicular control at high speed when driving in fog; however, it is important to note that drivers chose to drive at speeds where they would be incapable of stopping to avoid obstacles in the roadway even if they were to identify and react to the obstacle immediately at the border of visibility distance. This research suggests that safety benefits may be gained by convincing drivers to slow down more than they would on their own when driving in fog or enhancing a vehicles ability to identify and react to hazards that are not visible to the driver. In order to further understand the effects of driving in fog, future naturalistic driving research should focus on identifying and mitigating risky behaviors associated with driving in foggy conditions.

Physician Knowledge, Assessment, and Reporting of Older Driver Fitness

ABSTRACT Physicians have the potential to serve as an important portal for information gathering, assessment, counseling, and reporting older driver fitness, as almost all older adults require medical care and have a primary care physician. However, there are few studies that have evaluated physician knowledge about, attitudes toward, and performance of older driver fitness assessment. Two pilot studies were conducted to assess physician knowledge and attitudes and aid understanding of physician knowledge of legal reporting requirements regarding older driver medical fitness. Results suggest that although physicians believe that patients should be evaluated for safe driving, many physicians do not routinely assess fitness to drive and few feel qualified to do so. It also appears that physicians may not be adequately knowledgeable about laws about reporting unsafe drivers. Thus, occupational therapy practitioners have an opportunity to educate about driving as a complex instrumental activity of daily living.

Seniors’ and Physicians’ Attitudes Toward Using Driving Simulators in Clinical Settings

ABSTRACT Interactive driving simulators may offer a safe and controlled environment for occupational therapists to treat clients with conditions that affect their ability to drive safely. The use of simulators has been mostly limited to research settings. To make appropriate use of this technology, identifying and understanding the needs of clients and medical personnel that simulators can fulfill is important. The current investigation seeks to identify the attitudes of potential clients and physicians regarding the use of driving simulators. Using survey and interview methodology, clients’ and physicians’ needs in regard to driving and community mobility are investigated in the context of identifying potential applications for simulator technology. In addition, general needs and attitudes about driving in the context of medical practice were identified. Attitudes toward the use of simulators were generally positive, and the desire for a greater ability to understand and treat clients in the context of driving appears strong.

The DrivingHealth® Inventory as a clinical screening tool-assessment of face validity and acceptance.

ABSTRACT To investigate the use and potential for patient acceptance of the DrivingHealth® Inventory (DHI) in clinical practice, we administered the DHI to 360 community dwelling volunteers over age 50 at a Southeastern US rehabilitation hospital. Volunteers also completed surveys to document their health, driving habits, and impressions of the DHI. Volunteers reported strong agreement with statements that indicated that they believe the DHI measures abilities important for safe driving and that they would be willing to listen to advice about driving and safe mobility from medical professionals; however, responses to some items were more positive among drivers whose DHI results indicated no apparent loss of function that could impair driving. These results support the use of the DHI in clinical practice as a tool to raise awareness of factors that correlate to driving; however, further research will be necessary to investigate how the DHI may benefit diverse clinical populations. Experiences with using DHI as part of clinical practice are also discussed.

Effects of Upper Extremity Immobilization and Use of a Spinner Knob on Vehicle Steering

Background: A person’s ability to safely drive while immobilized is not well defined. Steering ability with a spinner knob during immobilization is unknown. The goal of this study is to further clarify the effect of immobilization on steering reaction time and accuracy with and without a steering wheel spinner knob. Methods: Twenty participants were enrolled in this crossover trial using a driving simulator with an automatic transmission. Five conditions were tested in a counterbalanced order. Steering reaction time and accuracy (number of errors on a dynamic steering task at 2 difficulty levels) were measured. Participants were allowed to steer with the immobilized extremity. Results: No significant differences in reaction time were observed between any conditions. Both immobilized conditions and difficulty level of the steering task led to diminished accuracy compared with controls, resulting in significantly more errors. The use of a spinner knob significantly improved the accuracy for the condition with the sugar-tong splint during the easier steering task, but this improvement was not observed in the harder steering task. There were no differences between conditions based on gender or observed use of the immobilized arm. Conclusions: Immobilization had a negative effect on steering accuracy for both the wrist splint and the sugar-tong splint condition, which may negatively impact driving ability of immobilized patients. Immobilization, regardless of spinner knob use, did not significantly impact steering reaction time. The steering wheel spinner knob did not consistently improve accuracy, and further study is needed to determine its utility.

Developing a Driving Simulator Based Functional Object Detection Task

ABSTRACT The purpose of this study was to validate a driving simulator-based tool for assessing functional visual scanning while driving (Goodenough, 2010) by replicating a previous study and assessing whether the results of the task are moderated by strategic decisions regarding task prioritization. Participants completed a functional object detection task that includes a peripheral target detection task and a central braking response task. Results indicated that the simulator task can identify differences in older and younger participants’ abilities to functionally scan the driving environment and these differences appear unaffected by prioritizing either the scanning or braking task. Implications are discussed.

Developing a new driving simulator task to assess drivers' functional object detection

A new driving simulator task was developed with the long-term goal of aiding rehabilitation specialists who work with drivers who may have functional impairments. This simulated driving task was designed to measure a drivers ability to respond to two types of visual stimuli - brake lights of a lead vehicle and targets presented at different eccentricities along the horizon. Three driving scenarios were developed for the study. The first two were used to examine the effect of A-pillar occlusion on the target detection task. The target locations used in the third scenario were chosen to examine the effect of eccentricity on target reaction time when the participant was required to make head movements to locate and respond to targets. This third scenario revealed age-related differences in the capability to locate and respond to visual stimuli in the periphery of the driving environment. This may be due to the decrements in psychomotor ability observed in older adults. This scenario is expected to have utility in clinical settings.

Interactive Tools for Measuring Visual Scanning Performance and Reaction Time

Occupational therapists are constantly searching for engaging, high-technology interactive tasks that provide immediate feedback to evaluate and train clients with visual scanning deficits. This study examined the relationship between two tools: the VISION COACH™ interactive light board and the Functional Object Detection© (FOD) Advanced driving simulator scenario. Fifty-four healthy drivers, ages 21–66 yr, were divided into three age groups. Participants performed braking response and visual target (E) detection tasks of the FOD Advanced driving scenario, followed by two sets of three trials using the VISION COACH Full Field 60 task. Results showed no significant effect of age on FOD Advanced performance but a significant effect of age on VISION COACH performance. Correlations showed that participants’ performance on both braking and E detection tasks were significantly positively correlated with performance on the VISION COACH (.37 < r < .40, p < .01). These tools provide new options for therapists.