Julie M. Drexler

Research in visually induced motion sickness

While humans have experienced motion sickness symptoms in response to inertial motion from early history through the present day, motion sickness symptoms also occur from exposure to some types of visual displays. Even in the absence of physical motion, symptoms may result from visually perceived motion, which are often classified as effects of visually induced motion sickness (VIMS). This paper provides a brief discussion of general motion sickness and then reviews findings from three lines of recent VIMS investigations that we have conducted.

Cybersickness is Not Simulator Sickness

Factor analysis of a large number of motion sickness self-reports from exposure to military flight simulators revealed three separate clusters of symptoms. Based on this analysis a symptom profile emerged for simulators where Oculomotor symptoms predominated, followed by Nausea and least by Disorientation-like symptoms. Current users of virtual environment (VE) systems have also begun to report varying degrees of what they are calling cybersickness, which initially appeared to be similar to simulator sickness. We have found, after examination of eight experiments using different VE systems, that the profile of cybersickness is sufficiently different from simulator sickness — with Disorientation being the predominant symptom and Oculomotor the least. The total severity of cybersickness was also found to be approximately three times greater than that of simulator sickness. Perhaps these different strains of motion sickness may provide insight into the different causes of the two maladies.

Motion sickness and proprioceptive aftereffects following virtual environment exposure

To study the potential aftereffects of virtual environments (VE), tests of visually guided behavior and felt limb position (pointing with eyes open and closed) along with self-reports of motion sickness-like discomfort were administered before and after 30 min exposure of 34 subjects. When post- discomfort was compared to a pre-baseline, the participants reported more sickness afterward (p < 0.03). The change in felt limb position resulted in subjects pointing higher (p < 0.038) and slightly to the left, although the latter difference was not statistically significant (p = 0.08). When findings from a second study using a different VE system were compared, they essentially replicated the results of the first study with higher sickness afterward (p < 0.001) and post- pointing errors were also up (p < 0.001) and to the left (p < 0.001). While alternative explanations (e.g. learning, fatigue, boredom, habituation, etc.) of these outcomes cannot be ruled out, the consistency of the post- effects on felt limb position changes in the two VE implies that these recalibrations may linger once interaction with the VE has concluded, rendering users potentially physiologically maladapted for the real world when they return. This suggests there may be safety concerns following VE exposures until pre-exposure functioning has been regained. The results of this study emphasize the need for developing and using objective measures of post-VE exposure aftereffects in order to systematically determine under what conditions these effects may occur.

A comparison of cybersickness incidences, symptom profiles, measurement techniques, and suggestions for further research

The widespread use of virtual environment (VE) systems in a variety of applications has serious implications for the user. Users with access to these sophisticated interactive immersions in multisensory, three-dimensional (3D) synthetic environments have been shown to experience motion sickness-like symptoms (i.e., eyestrain, ataxia, fatigue, drowsiness) and aftereffects such as visual flashbacks, disorientation, and balance disturbances occasionally occurring up to 12 hours after VE exposure. This is a significant health and safety concern. Technical improvements of VE systems need to be initiated to reduce these potential aftereffects that could result in adverse legal, economic, individual, and social consequences. Many different types of symptoms have been reported that appear to make up the cybersickness syndrome. From our extensive database of virtual environment and flight simulator exposures, we offer examples of these symptoms profiles along with suspected mechanisms and origins. We discuss these issues as well as various assessment techniques and methods used to determine the presence of VE sickness in individuals.

Impact of Automation and Task Load on Unmanned System Operator's Eye Movement Patterns

Eye tracking under naturalistic viewing conditions may provide a means to assess operator workload in an unobtrusive manner. Specifically, we explore the use of a nearest neighbor index of workload calculated using eye fixation patterns obtained from operators navigating an unmanned ground vehicle under different task loads and levels of automation. Results showed that fixation patterns map to the operators experimental condition suggesting that systematic eye movements may characterize each task. Further, different methods of calculating the workload index are highly correlated, r(46) = .94, p = .01. While the eye movement workload index matches operator reports of workload based on the NASA TLX, the metric fails on some instances. Interestingly, these departure points may relate to the operators perceived attentional control score. We discuss these results in relation to automation triggers for unmanned systems.

A Portable Device for Dynamic Visual Acuity

Dynamic visual acuity (DVA) thresholds are among the few visual functions found predictive of automobile accidents. DVA is sensitive to alcohol and aging. In two within-subject, repeated-measures designs, a laser DVA device was compared to the traditional device. Both tasks were administered to two groups: Group I received graded stimuli at 60, 75 & 90 degrees per second (dps); Group II at 60, 90 & 120 dps. Testing involved different target sizes, velocities, type of target, and time course changes within a session. Findings: 1) retest reliabilities of the two DVA devices were comparable and higher with the laser; 2) average correlations between the devices were r = 0.62 (p < .01) and r = 0.65 (p < .01) for Group I and II respectively. In spite of the known differences in implementation, the laser device can be developed to measure the same construct as the more traditional DVA device, and the laser is considerably more flexible.

Developing impact assessment for training systems research & development: A case study of the strategic approach for the NEWIT system

Impact assessment seeks to evaluate the effects of a new system realized on target beneficiaries and is an essential process via which to tangibly demonstrate the operational and economic benefits of a research and development (R&D) program. This paper contributes a framework –Program-management Understanding, Measurement, and Assessment (PUMA) - for developing an impact assessment approach for planning and evaluating R&D programs. The intent of the framework is to help an R&D organization provide traceability from the identification of program needs to selecting and conducting R&D to implementation to defining and measuring results. The framework is demonstrated using an Office of Naval Research project.

New Kids on the Block: Multi-Dimensional Perspectives on Augmented Cognition

This discussion panel was organized to offer HFES members an opportunity to learn more about the burgeoning field of Augmented Cognition and to discover the multi-dimensional aspects of the discipline. The session will feature six invited panelists who were selected to represent a cross-section of the Augmented Cognition International Society community of more than 900 members. Each panelist will present their unique perspective of the AugCog field, which will provide the audience with information on a variety of research, development, and application areas in the AugCog field within the U.S and abroad. The panel members and their associated AugCog perspectives include: CDR Dylan Schmorrow, government; Denise Nicholson, academia; Dennis McBride, non-profit; Kay Stanney and Chris Berka, industry; and Blair Dickson, industry/international.

Aiding tomorrow's augmented cognition researchers through modeling and simulation curricula

Research in the newly emerged field of Augmented Cognition (AugCog) has demonstrated great potential to develop more intelligent computational systems capable of monitoring and adapting the systems to the changing cognitive state of human operators in order to minimize cognitive bottlenecks and improve task performance. As the AugCog field rapidly expands, an increasing number of researchers will be needed to conduct basic and applied research in this burgeoning field. However, due to its multidisciplinary nature and cutting-edge technological applications, most traditional academic disciplines cannot support the training needs of future AugCog researchers. Accordingly, an established Modeling and Simulation (M&S) graduate curriculum is described, which provides a broad basis of interdisciplinary knowledge and skills as well as depth of knowledge within a specific area of the M&S field. Support for use of the flexible M&S curriculum to provide the requisite multifaceted foundational training in Augmented Cognition principles is also presented.

Visually-Induced Motion Sickness: Effects of Adaptation

This research was designed to empirically examine the effect of adaptation training using a simulated rotary stimulation (SRS) technique on simulation sickness and inducing graded motion sickness through the systematic distortion of the relevant characteristics of two VR devices (VE and optokinetic OKN drum). Forty participants were randomly assigned to either a control (no training with SRS) or experimental (4-day training with SRS) condition. The results indicated that the experimental group who had prior training with SRS reported lower DLQ scores (Mean=2.09) than the control group participants (Mean=4.09) following VE exposure. Similarly, the experimental group who had prior training with SRS reported lower DLQ scores (Mean=1.95) than the control group participants (Mean=3.68) following OKN exposure. With regard to SSQ scores, the experimental group who had prior training with SRS reported significantly lower SSQ scores following the day 5 SRS exposure (Mean= 11.49) than the control group (Mean=1.60). Furthermore, the experimental group who had prior training with SRS reported significantly lower SSQ scores (Mean=11.75) than the control group participants (Mean=22.71) following VE exposure.