Enhancing virtual environment spatial awareness training and transfer through tactile and vestibular cues.

Haptic interaction has been successfully incorporated into a variety of virtual environment (VE) systems, yet designing multimodal VE training systems remains challenging as each cue incorporated during training should maximise learning and training transfer. This study examined the impact of incorporating two independent, spatialised tactile cues and vestibular cues into a military VE training environment with the goal of empirically examining whether such cues could enhance performance within the training environment and also that knowledge and skills gained during training could transfer to another environment. The results showed that tactile cues enhanced spatial awareness and performance during both repeated training and within a transfer environment, yet there were costs associated when two independent tactile cues were presented during training. In addition, results suggest that spatial awareness benefits from a tactile point indicator may be impacted by vestibular cues, as performance benefits were seen when tactile cues were paired with head tracking. To fully realise training potential, it is essential to determine how best to leverage multimodal capacity of VE training systems by identifying how multimodal training cues may advance knowledge, skills and attitudes of trainees. Results from this study provide design guidelines for incorporating tactile cues in VE training environments to enhance spatial awareness.

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.

Postural instability induced by virtual reality exposure: development of a certification protocol.

Exposure to virtual environments often causes users to experience symptoms of motion sickness. An accessory manifestation of motion sickness symptoms is postural disequilibrium. If the postural disequilibrium that occurs persists beyond the time an individual is within the confines of the laboratory or system site, user safety could be compromised and products liability issues could be forthcoming. In this study, a portable, automated postural assessment system is developed that can be employed before and after exposure to a virtual reality (VR) system in order to certify that a user's balance on exiting the system is at least demonstrably as good as it was on entering. It is argued that if the "coming out" balance performance is sufficiently poorer than the "going in" balance, then the user should be retained until the pretest balance performance is regained. The results from a set of normative and validation experiments on postural equilibrium identified several reliable measures of stance that could serve as a basis for certification. Furthermore, a new automated video-based measure using only head movement showed that performance over sessions is stable and reliable. The head movement changes that occur with stimuli, such as alcohol and simulator exposure, are well behaved, predictable, and significant even with small samples. The implication is that the proposed objective measure of postural stability, in conjunction with procedures for obtaining self-reports of symptoms, can afford some measure of certification that exposure to a given VR system is without harm.

Information visualization; assisting low spatial individuals with information access tasks through the use of visual mediators.

This study investigated the use of visual mediators to facilitate information access by low spatial individuals. Based on theories of adaptive learning and field-dependence, two human-computer interfaces were developed which were intended to compensate for the inability of low spatial individuals to readily construct visual mental models of a menu system's structure. The two compensatory interfaces included: a 2D visual hierarchy and a linear structure. The information search performance of high and low spatial individuals was compared on the two compensatory interfaces and a third challenge match interface, which challenged individuals to construct a mental model of a hierarchical menu system in order to perform efficiently. The visual mediators were successful in accommodating low spatial individuals, as indicated by the lack of any significant performance differences being detected between the high and low spatial groups on the two compensatory interfaces. High spatial individuals outperformed low spatial individuals only when information search tasks required the use of spatial ability in mentally constructing a model of the organization and structure of embedded task information. The key factor in the accommodation process was the elimination of the need to mentally visualize the structure of embedded task information. These results indicate that visualization techniques can be successfully used to enhance the information search performance of low spatial individuals.

Effects of diversity in cognitive restructuring skills on human-computer performance.

The objective of this study was to determine if more efficient performance in hierarchical computer environments could be obtained from field-dependent (low technical aptitude) individuals by manipulating information structuring requirements. A three-dimensional (task complexity, quality of integration, and level of differentiation) conceptual model was proposed to explain differences in memory organization which were suggested to lead to computer performance differences. The model was tested with 36 subjects, 18 identified as field-dependent and 18 as field-independent. The subjects performed the information search task under three task conditions, two structured by the experimenter and one by the subjects. The results indicated that the effects of differences in the organization of task information on computer performance time can be controlled for by providing subjects with a period of time dedicated to the acquisition of a system's structure.