One of our most active areas of research is investigation of the potential of virtual reality (VR) as an intervention tool in rehabilitation. Virtual reality entails the use of advanced technologies, including computers and various multimedia peripherals, to produce a simulated (i.e., virtual) environment that users perceive as comparable to real world objects and events. Users interact with displayed images, move and manipulate virtual objects, and perform other actions in a way that engenders a feeling of actual presence, and immerses their senses in the simulated environment. Users are provided with visual, audio and, in some instances, haptic (the sense of touch) and olfactory feedback of their performance. These unique characteristics of virtual reality set it apart from other engaging experiences such as watching television, reading books, and even playing traditional computer simulation games.
Virtual reality may be delivered to the user via a variety of different technologies (e.g., flat screen monitor, projected 3-D image, head-mounted display) that differ in their ability to engender a sense of immersion within the simulated environment and a concomitant feeling of “presence”. They also differ in the degree to which users experience “cyber-sickness”, VR-generated side effects that may include nausea, disorientation and in-coordination both during and following exposure to virtual environments. The relation between VR system attributes, immersion and side effects is the focus of considerable research.
Relevance of virtual reality to occupational therapy
An essential part of the rehabilitation process is remediation of cognitive and motor deficits in order to improve the functional ability of the patient, and to enable him or her to achieve greater independence. Since the ultimate goal of rehabilitation is to maximize a patient’s independence in activities related to daily performance skills, the functional relevance of therapeutic intervention is of paramount importance. Occupational therapy may be defined as interventions, which use purposeful activity designed to promote functional outcomes for the enhancement of health and the prevention of injury or disability. This is achieved in two, complementary ways - repetition of the function that is desired (known as the functional/adaptive approach) and treatment of specific motor or cognitive impairments (known as the remedial approach).
One of the dilemmas of conventional occupational therapy is the limited opportunities for implementing purposeful activities within traditional clinical settings. For example, it is time-consuming to teach a homemaker who has sustained a cerebral stroke to cope with cooking and self care tasks in her own home, although this is the environment in which such instruction would be most constructive. It is dangerous to teach an elderly man with Parkinson’s disease to cross a busy street, yet impractical to construct a realistic physical mock-up of such a task. It is expensive to assemble the materials needed to teach blind children to navigate in novel settings, yet research has shown that greater independence in mobility has far reaching psychological and emotional effects. For these reasons “real life”, environmentally-valid sites are seldom used, and realistic simulated environments are difficult to achieve. As a result, patients have few opportunities to engage in purposeful and meaningful tasks.
VR has the potential to be used as a novel modality in rehabilitation assessment and intervention due to a number of unique attributes. These include the ability to objectively measure behaviour in challenging but safe and ecologically-valid environments, while maintaining strict experimental control over stimulus delivery and measurement. VR also offers the capacity to individualize treatment needs, while providing increased standardization of assessment and re-training protocols. It is common for patients to “practice” the use of compensatory strategies within the traditional rehabilitation setting, in the hope that these skills will generalize to their home environment. However, this approach is labor intensive, limited in intensity and duration of repetitions, and with uncertain efficacy outside of the rehabilitation setting. VR can help to address these limitations by allowing the development of low-cost training environments consistent with the client’s home environment. Furthermore, virtual environment's can provide repeated learning trials and offer the capacity to gradually increase the complexity of tasks while decreasing the support/feedback provided by the therapist.
Until recently, the application of VR technology in rehabilitation was severely limited by the lack of inexpensive, easy-to-maintain and easy-to-use VR systems. The vast majority of the studies carried out in the past decade used custom applications that were relatively expensive and technically complex. VR applications in medicine and rehabilitation are a relatively recent occurrence made possible by technological developments that have led to decreases in cost and increases in ease of use and in the availability of off-the-shelf programs. For example, VR has been used to train surgical residents to carry out of a variety of invasive procedures such as knee arthoscopy. Medical students have been taught to palpate tumors and to insert epidural anesthesia. The treatment of psychological dysfunction including phobias, post-traumatic stress disorder, and eating and body image disorders have been highly successful. Recently, VR has been used as a medium for the assessment and rehabilitation of cognitive processes, such as visual perception and executive functioning and for training instrumental activities of daily living, such as the use of public transportation, and meal preparation tasks.