User-centered virtual environment design for virtual rehabilitation

<p>Abstract</p> <p>Background</p> <p>As physical and cognitive rehabilitation protocols utilizing virtual environments transition from single applications to comprehensive rehabilitation programs there is a need for a new design cycle methodology. Current human-computer interaction designs focus on usability without benchmarking technology within a user-in-the-loop design cycle. The field of virtual rehabilitation is unique in that determining the efficacy of this genre of computer-aided therapies requires prior knowledge of technology issues that may confound patient outcome measures. Benchmarking the technology (e.g., displays or data gloves) using healthy controls may provide a means of characterizing the "normal" performance range of the virtual rehabilitation system. This standard not only allows therapists to select appropriate technology for use with their patient populations, it also allows them to account for technology limitations when assessing treatment efficacy.</p> <p>Methods</p> <p>An overview of the proposed user-centered design cycle is given. Comparisons of two optical see-through head-worn displays provide an example of benchmarking techniques. Benchmarks were obtained using a novel vision test capable of measuring a user's stereoacuity while wearing different types of head-worn displays. Results from healthy participants who performed both virtual and real-world versions of the stereoacuity test are discussed with respect to virtual rehabilitation design.</p> <p>Results</p> <p>The user-centered design cycle argues for benchmarking to precede virtual environment construction, especially for therapeutic applications. Results from real-world testing illustrate the general limitations in stereoacuity attained when viewing content using a head-worn display. Further, the stereoacuity vision benchmark test highlights differences in user performance when utilizing a similar style of head-worn display. These results support the need for including benchmarks as a means of better understanding user outcomes, especially for patient populations.</p> <p>Conclusions</p> <p>The stereoacuity testing confirms that without benchmarking in the design cycle poor user performance could be misconstrued as resulting from the participant's injury state. Thus, a user-centered design cycle that includes benchmarking for the different sensory modalities is recommended for accurate interpretation of the efficacy of the virtual environment based rehabilitation programs.</p

Game invaders: the theory and understanding of computer games

"Introduces a practical critical method for analyzing existing games and designing future games

Developing a virtual reality-based methodology for people with dementia: a feasibility study

The aim of this study was to examine the feasibility of virtual reality (VR) technology for use by persons with dementia (PWD). Data were obtained directly from six PWD regarding their experiences with a virtual environment (VE) of a large outdoor park. A user-centered method was developed to assess: (a) presence, (b) user inputs, (c) display quality, (d) simulation fidelity, and (e) overall system usability. The extent to which PWD could perform four functional activities in the VE was also investigated (e.g. mailing a letter). In addition, physical and psychological well-being of PWD while interacting with the VE was assessed objectively by recording heart rate during the VR sessions and subjectively with discrete questionnaire items and real-time prompts. Symptom profiles associated with simulator sickness were assessed with an adapted version of the Simulator Sickness Questionnaire. The study found that PWD to some extent experienced presence, perceived that objects were realistic and moved naturally, generally felt in control of the interaction, and demonstrated little difficulty using a joystick for navigation. The study also demonstrated that VR is an appropriate medium for assessing functional behaviour within the context of an ecologically valid VE. PWD did not experience any significant increase in symptoms associated with simulator sickness, or detriments to their psychological and physical well-being. These findings demonstrated that it is feasible to work in VEs with PWD