Thomas A. Furness

Virtual reality as an adjunctive pain control during burn wound care in adolescent patients

Abstract For daily burn wound care procedures, opioid analgesics alone are often inadequate. Since most burn patients experience severe to excruciating pain during wound care, analgesics that can be used in addition to opioids are needed. This case report provides the first evidence that entering an immersive virtual environment can serve as a powerful adjunctive, nonpharmacologic analgesic. Two patients received virtual reality (VR) to distract them from high levels of pain during wound care. The first was a 16‐year‐old male with a deep flash burn on his right leg requiring surgery and staple placement. On two occasions, the patient spent some of his wound care in VR, and some playing a video game. On a 100 mm scale, he provided sensory and affective pain ratings, anxiety and subjective estimates of time spent thinking about his pain during the procedure. For the first session of wound care, these scores decreased 80 mm, 80 mm, 58 mm, and 93 mm, respectively, during VR treatment compared with the video game control condition. For the second session involving staple removal, scores also decreased. The second patient was a 17‐year‐old male with 33.5% total body surface area deep flash burns on his face, neck, back, arms, hands and legs. He had difficulty tolerating wound care pain with traditional opioids alone and showed dramatic drops in pain ratings during VR compared to the video game (e.g. a 47 mm drop in pain intensity during wound care). We contend that VR is a uniquely attention‐capturing medium capable of maximizing the amount of attention drawn away from the ‘real world’, allowing patients to tolerate painful procedures. These preliminary results suggest that immersive VR merits more attention as a potentially viable form of treatment for acute pain.

Virtual reality in the treatment of spider phobia: a controlled study

This study explored whether virtual reality (VR) exposure therapy was effective in the treatment of spider phobia. We compared a treatment condition vs. a waiting list condition in a between group design with 23 participants. Participants in the VR treatment group received an average of four one-hour exposure therapy sessions. VR exposure was effective in treating spider phobia compared to a control condition as measured with a Fear of Spiders questionnaire, a Behavioural Avoidance Test (BAT), and severity ratings made by the clinician and an independent assessor. Eighty-three percent of patients in the VR treatment group showed clinically significant improvement compared with 0% in the waiting list group, and no patients dropped out. This study shows that VR exposure can be effective in the treatment of phobias.

Effects of Image Scale and System Time Delay on Simulator Sickness within Head-Coupled Virtual Environments

Novel patterns of visual-vestibular intersensory stimulation often result in symptoms of simulator sickness, raising health and safety concerns regarding virtual environment exposure. Two experiments investigated the effect of conflicting visual-vestibular cues on subjective reports of simulator sickness during and after a 30-min exposure to a head-coupled virtual interface. Virtual image scale factors (0.5, 1.0, 2.0 magnification, generated by varying geometric field of view angle) were investigated in Experiment 1, and additional system time delays (125, 250 ms) were investigated in Experiment 2. Simulator sickness metrics included spoken self-reports during exposure and simulator sickness questionnaires (pre-exposure, immediate postexposure, and 20 min postexposure). Head yaw angular position data were also recorded. Reports of simulator sickness symptoms were significantly greater in the minification (0.5) and magnification (2.0) image scale factor conditions than in the neutral condition (1.0). Simulator sickness did not vary with changes in time delay, however. Furthermore, a comparison across experiments suggests no appreciable increase in simulator sickness with increasing time delays above the nominal value (48 ms). Head angular position data exhibited certain systematic variations across conditions. Actual or potential applications of this research include virtual environment training, simulation, and entertainment systems.

Spatial perception in virtual environments: Evaluating an architectural application

An experiment was conducted to compare and explore the relationship between the way people perceive real and virtual spaces. Twenty-four architects toured either a real museum gallery or a realtime computer generated model of the same gallery under one of three increasingly inclusive viewing conditions, i.e., looking at a monitor, viewing through stereoscopic head-mounted displays without and with head-position tracking. Subjects were asked to perform spatial dimension, orientation and evaluation tasks. The most significant results indicate that subjects consistently underestimate the dimensions of the gallery in all three computer simulation conditions when compared to touring the real gallery. The most inclusive viewing condition yields underestimates for spatial dimensions which are significantly greater than the other two simulation conditions.<<ETX>>

Conflicting motion cues to the visual and vestibular self-motion systems around 0.06 Hz evoke simulator sickness.

The basic question this research addressed was, how does simulator sickness vary with simulated motion frequency? Participants were 11 women and 19 men, 20 to 63 years of age. A visual self-motion frequency response curve was determined using a Chattecx posture platform with a VR4 head-mounted display (HMD) or a back-projected dome. That curve and one for vestibular self-motion specify a frequency range in which vestibular and visual motion stimuli could produce conflicting self-motion cues. Using a rotating chair and the HMD, a third experiment supported (p < .01) the hypothesis that conflicting cues at the frequency of maximum “crossover” between the curves (about 0.06 Hz) would be more likely to evoke simulator sickness than would conflicting cues at a higher frequency. Actual or potential applications of this work include a preliminary design guidance curve that indicates the frequency range of simulated motion that is likely to evoke simulator or virtual reality sickness; for simulators intended to operate in this frequency range, appropriate simulator sickness interventions should be considered during the design process.

Wearable computers for three dimensional CSCW

Using established principles from the field of Computer Supported Collaborative Work (CSCW), we describe how wearable computers are ideal platforms for three dimensional CSCW. To illustrate this, we present two pilot studies which imply that wearables may be able to support three dimensional collaboration and that users will perform better with these interfaces than immersive collaborative environments.

Shared space: An augmented reality approach for computer supported collaborative work

Virtual Reality (VR) appears a natural medium for three-dimensional computer supported collaborative work (CSCW). However the current trend in CSCW is to adapt the computer interface to work with the users traditional tools, rather than separating the user from the real world as does immersive VR. One solution is through Augmented Reality, the overlaying of virtual objects on the real world. In this paper we describe the Shared Space concept—the application of Augmented Reality for three-dimensional CSCW. This combines the advantages of Virtual Reality with current CSCW approaches. We describe a collaborative experiment based on this concept and present preliminary results which show that this approach may be better for some applications.

The Virtual Retinal Display: A new Display Technology using Scanned Laser Light

The Virtual Retinal Display (VRD) is a new display technology that scans modulated low energy laser light directly onto the viewers retina to create a perception of a virtual image. This approach provides an unprecedented way to stream photons to the receptors of the eye, affording higher resolution, increased luminance, and potentially a wider field-of-view than previously possible in head coupled displays. The VRD uses video signals from a graphics board or a video camera to modulate low power coherent light from red, green and blue photon sources such as gas lasers, laser diodes and/or light emitting diodes. The modulated light is then combined and piped through a single mode optical fiber. A mechanical resonant scanner and galvanometer mirror then scan the photon stream from the fiber in two dimensions through reflective elements and semitransparent combiner such that a raster of light is imaged on the retina. The pixels produced on the retina have no persistence, yet they create the perception of a brilliant full color, and flicker-free virtual image. Developmental models of the VRD have been shown to produce VGA and SVGA image quality. This paper describes the VRD technology, the advantages that it provides, and areas of human factors research ensuing from scanning light directly onto the retina. Future applications of the VRD are discussed along with new research findings regarding the use of the VRD for people with low vision

An “independent visual background” reduced balance disturbance envoked by visual scene motion: implication for alleviating simulator sickness

Simulator sickness (SS) / virtual environment (VE) sickness is expected to become increasingly troublesome as VE technology evolves [20]. Procedures to alleviate SS / VE sickness have been of limited value [12]. This paper investigated a possible procedure to reduce SS and VE sickness. Postural disturbance was evoked by visual scene motion at different frequencies. Differences in disturbance were examined as a function of simultaneous exposure to an “independent visual background” (IVB). Eight subjects were tested at two scene motion frequencies and three different IVB conditions using a within-subjects design. An expected statistically significant interaction between IVB condition and frequency was observed. For low frequency scene movements, subjects exhibited less balance disturbance when the IVB was presented. We suggest that an IVB may alleviate disturbance when conflicting visual and inertial cues are likely to result in simulator or VE sickness.

Foreground/Background Manipulations Affect Presence:

A possible relation between vection and presence is discussed. Two experiments examined the hypothesis that “presence” is enhanced by manipulations which facilitate interpreting visual scenes as “background.” A total of 39 participants in two experiments engaged in a pursuit game while in a virtual visual environment generated by an HMD and rated their experience of “presence” on 5 questions. Experiment 1 compared two viewing conditions: visual scene masking at the eye and a paper mask mounted on the screen with the same 60° FOV, and showed that presence was enhanced by eye masking relative to screen masking. Experiment 2 replicated these findings with a double-blind experimental design.