Literature Review on Virtual Reality for Rehabilitation

Literature Review on Virtual Reality for Rehabilitation

2.0       Literature Review

2.1       Theoretical analysis of virtual reality for rehabilitation

Zhang, Abreu, Seale, Masel, Christiansen & Ottenbacher (2008) acclaims that with the current technological advancements that have swept over the world, virtual reality has been transformed to provide real time interaction between the users and the environment. The process is simulated using a computer aided program that facilitates creation of virtual primary experiences that are displayed on dedicated stereoscopic displays (Zhang et al, 2008). In addition to the displays, information is simulated into codes that can be sensed using speakers, felt through haptic systems and virtualized via virtual artifacts. Burdea, (2006) states that the simulation can be transmitted to a multimodal device which is wired to a multidirectional treadmill. According to research by Burdea, (2006) attempts to innovatively create virtual reality systems with high fidelity has been limited by technicalities emanating from communication bandwidth, image resolutions and processing power.

Michael Heim supports that virtual reality has a bright future citing the current improvement of modeling and development of processors with high capabilities (Chuang, Chen, Chang, Lee, Chou & Doong, 2003). Likewise there has been increased research on CAD software programs, head mounted displays and graphic accelerator hardware programs. Michael further uses his book “The Metaphysics of Virtual Reality” to postulate vital components of a virtual reality system which has of late been integrated into rehabilitation facilities to aid patients with diseases such as dyskinesia (Chuang et al, 2003). The seven concepts are simulation, interaction, artificiality, immersion, telepresence, full-body immersion, and network communication. Contrary to virtual reality which was first used by Antonin Artaud, Myron Krueger is believed to have premised the term artificial reality in the 1970’s (Brooks, 1999).

Robles-De-La-Torre, 2006 states that the book “Multimedia: from Wagner to Virtual Reality” which was authored through joint efforts between Ken Jordan and Randall Packers in 2001 gives an elaborate account into the historic use of the word virtual and its connection with reality as well as technology (Ken & Randall, 2001). Krueger supports that the term reality elaborates anything that exists in the environment in the form of physical or functional models that can actually be achieved (Robles-De-La-Torre, 2006). On the other hand the term virtual according to Philip a computer-generated technology that attempts to simulate a real world scenario therefore combining the two terms results into virtual reality which refers to a kind of special computer-generated environment by which one can use a variety of special devices to simulate their own perceptions into real life environment by manipulating and controlling the environment in order to achieve a special purpose (Schultheis, Albert & Rizzo, 2011).

Phillip Zhai also shows his undying interest in exploring the topic of virtual reality which he abbreviates as VR Soon after Philips illustration of the definition of VR with relation to rehabilitation, Blascovich and Bailenson also made reviews of the same literature which Phillip had made in favor of the medical profession, meanwhile Brascovich and Bailenson coined VR to suit into both sociological and psychological contexts (Merians, Jack, Boian, Tremaine, Burdea, Adamovich, Recce & Poizner, 2002). Apparently many more authors were beginning to gain a deeper insight into the topic of virtual reality and as a result, they intensified their efforts towards research and interconnection of various concepts to the medical field. It is during this time that Mychilo Cline described VR as being a determinant towards better lives for the paralyzed and ill fated patients who become maimed by accidents.

Steele, Grimmer, Thomas, Mulley, Fulton & Hoffman, (2003) state that this statement was implicit in the works “Power, Madness, and Immortality: The Future of Virtual Reality” in the book Cline supports empirical findings that portrayed VR as a game changer for distressed patients since the bare mention of the word virtual is by itself a motivation to patients who are bound to enjoy despite their physical incapacitation. At that time in history, Cline showed his optimism when he reached a conclusion that VR would be a suitable way to restore happiness for patients who had given up on their daily routines because of incapacitation from dyskinesia. Klein, Freimuth, Monkman, Egersdörfer,  Meier, Böse, Baumann, Ermert & Bruhns, (2005) also supports that the integration of VR into telepresence technologies as well as simulation of CAD technologies would advance cognitive and interpersonal communication between computers aided machines and human being and as a result facilitate hearing, sense and sight.

It is from the various definitions and perceptions towards virtual reality and rehabilitation that the term virtual rehabilitation was coined with the intention that it would help change economic, social and medical perspective of patients through offering of therapeutic training to patients. Therefore virtual rehabilitation is a psychological therapy that is devoid of conventional therapeutic practices. Professors Grigore Burdea and Daniel Thalmann were applauded for formulating the term virtual rehabilitation in the year 2002. The term has since come to include reality which then becomes virtual reality rehabilitation.  Both Burdea and Thalmann support that virtual reality rehabilitation is applicable to cognitive interventions and physical therapies aimed at de-stigmatizing patients acutely affected by chronic illnesses, post-traumatic stress disorders, amnesia and phobias. The International Society of Virtual Rehabilitation has also been involved in the creation of a virtual community which has been generally advantageous because it is more entertaining than the conventional therapies; the use of automated systems provides precise measurements of physical outcomes relating to efficiency of therapies such as error rates, game scores and limb velocities among other activities. The system provides real time dissemination of transparent data to internet databases for storage. Lastly virtual rehabilitation can be conducted in the patient’s home in what Burdea and Thalmann described as telerehabilitation.

Kanade identified that computer technologies which entail software and hardware programs have facilitated the simulation of three dimensional environments. The simplistic designs that first marked virtual reality rehabilitation have been advanced with time to integrate powerful Computer Aided Designs abbreviated as CAD models. The functionality of VR which is an affordable technological simulation enables practical visualization of the real world specifically in clinical medicine ranging from telemedicine, psychiatry and surgical planning. Grealy, Johnson & Rushton, (2009) supportsthat VR systems have inert capabilities meant to facilitate control and creation of not only dynamic 3-D (dimensional) models but also environments suited to ecological stimulus aimed at altering behavior. The VR systems perform these functions by measuring and recording assessments made by clinicians at the rehabilitation centers. Fortunately, Adamovich, Merians, Boian, Tremaine, Burdea, Recce & Poizner, (2003) adds that it is a modern technology that has more advantages compared to traditional methods implemented at some rehabilitation centers.

In this report, there arises the need to focus on a specific segment of virtual reality and this is the virtual reality for walking rehabilitation. Rensink, Klein, Freimuth, Monkman, Egersdörfer & Bauman, 2008).This medical practice is increasingly becoming applicable and common among patients suffering from dyskinesia. Apparently there has been a changing perception regarding VR systems on movement and walking. Whereas the speed of walking is influenced by visual gains, walking interfaces and audio tempo, the ratio of walking is collectively influenced by visual gain and walking interface as well. On the other hand, Sandlund, McDonough & Häger-Ross, (2010) identified that the perception proceeding self-motion is determined by visual cues exhibited by peripherals, field of view, visual gain, contrast and geometrical scaling. The instantaneous application of these mathematical principles and geometric scales could help patients optimize their walking performance.

To further elucidate on the need for VR for walking rehabilitation, several authors support that there exists correlation between disrupted walking and body injuries. Some injuries are often so deep that they exist even after specialized treatment thus therapies are often recommended but in the event that the patient exhibits slow, painful or poor walking then such a condition will definitely impact on the patients self-esteem. However therapies do not guarantee quick results because at times the healing process is often unpleasant this initiates the need for combination of physical therapy with the virtual reality to form what Bergeron, (2003) describes as Virtual Rehabilitation. With this computerized form of monitoring health and helping the patients go through traumatizing moments, VR for rehabilitation has been established as increasing the engagement of patients, decreasing perception of pains and making the patients feel better about themselves. Eru, (2012) reiterates that rehabilitation therapy can be made more efficient for maximum results by transforming treadmill mediation with the virtual reality systems which then facilitate proper walking.

To advance on the topic of motion and rehabilitation, walking is a combination of factors. Among the factors is the component of length of step which is identified as spatial in the medical world while the second component is cadence commonly known as temporal.  Spatial or length of step is the distance between the feet when a person is walking. Cadence on the other hand illustrates the frequency of the steps. From these examples of walking there emanates the need for coordination between virtual reality while walking should be equal to walking in real life scenarios. Mackey, Ada, Heard, & Adams, (2006) states that with the use of the computer aides system as described by various authors in the preceding chapters, the rate of movement in human beings is regulated by visual integration proprioceptive and vestibular information coded into the VR system. 

There should be congruence between the rehabilitator instruments and real world experiences because the inception and internalization of walking behavior is guided by sensory integration therefore deviations between virtual environment created by the VR systems and real ground walking should be minimized because failure to regulate deviations could negatively impact the patients perception towards self-movement or walking behavior. Driven by the need to attain utmost accuracy and precision, VR applications are coded as software programs with inbuilt virtual environments capable of performing various purposes. Powell, (2011) identifies that these applications have been supported by emerging technological research and development which have provided designs, calibrations and software programming content that has revolutionized the perception of virtual environments.

From the illustrations, there is enough verification that the idea of creating a virtual world through simulation of Computer Aided Designs so as to produce virtual 3 dimension scenes is not a misplaced priority in the rehabilitation industry. In fact Grealy, Johnson and Rushton (2009) supports that a VR system has inert capabilities that can create 3-D virtualization of the real world. Actually the simulation of Computer Aided Rehabilitation Environment abbreviated as CAREN presents the main idea behind the interplay between the rehabilitative training of disabled patients and the technology behind the production of 3-D scenes to create a proper visual environment that resembles actual ground or environment. Adamovich, Merians, Boian, Tremaine, Burdea, Recce & Poizner, (2003) stipulates that the technology behind the formation of 3-dimensional scenes has been endorsed to 3dmax and d-flow software programs. Likewise the software programs are used in the project that aims at explaining the essentials of a VR rehabilitation facility and how they positively impact on the disabled patients. In addition to these two the software market has several others that have the ability to develop virtual environments in order to boost the formation of 3-D scenes among them being Maya, UG, Solidworks, etc. Of them all, 3dmax and Maya is the most mainstream software.

2.2.      Conceptual framework

            The materialization of a VR system and consequently its integration into rehabilitation programs in most medical fields arouses the need for concepts behind the functioning of essential functions. Especially the simulation past where the following three concepts come into play. First, this report is motivated by the need to solve problems accruing from techniques such as deceptive existence. Rydmark, Boeren & Pasher, (2006) illustrate that The deceptive existence technique is a concept that link inputting of information into the virtual reality machines in order to ensure consistence with the patient’s sensory organs. From this realization, there arises the need for simulation of touch, sight and smell that resembles real life. The second concept is interaction which emphasizes on the need for creation of a virtual reality that interconnects different viewpoints including foresights and a higher level of sensory simulation which enables a patient to see, feel and touch the objects in the surrounding like he would do in real life. The third concept under discussion is self-discipline reality which enables the patients using VR for rehabilitation to gain senses which then help create a sense of reality from within and this enhances the patient’s self-esteem. With such levels of self-awareness and reality, the observers who in this case are patients in a VR rehabilitation facility will enable the observers, sensors, the computer simulation system, and display system to constitute a closed-loop process interaction (Piron, Tonin, Piccione, Iaia, Trivello & Dam, 2005).

In order to attain efficiency by applying these three aspects of conceptualization, again the topic of CR and its correspondence with multi-sensory is brought into light. A multi-sensory system integrates auditory perception, haptic perception, tactile perception, motion perception, taste perception and olfactory perception. Ideal virtual reality technology should have all perceptions that can enlighten patients at various stages of their rehabilitation exercise (Roudavski, 2010). Because of the constraints set by limitations in technological development especially the sensing technology, the current virtual reality technology only has the sensing functions of visual, auditory, haptic and tactile which are rather inclusive but limiting in the scope of creating a more dynamic multisensory VR systems.

There further arises the need to integrate immersion especially in the telepresence machine. According to Rizzo, Dorothy & Stéphane, (2007), telepresence aims to giving the user or the patient feelings of a real world even though the environment is simulated. An ideal simulation environment should make it difficult for the users to distinguish between truth and simulation, allowing users to dedicate themselves fully to a three-dimensional virtual environment created by the computer aided design system. In such an environment, Westwood, Helene, Hoffman, Haluck, Mogel, Phillips, Richard, Robb & Vosburgh, (2005) reiterates that everything seems to be true, because the voices are simulated to sound really, move real, even smells, tastes and feelings. Interplaying immersion and interactivity interplays to form an operational level that uses objects within the simulation environment and the real-time users that gets feedback from the environment. For example, the user can directly grab virtual objects in simulated environment, then they get the feeling that holding things in hands and the weight of them, and objects in vision can move immediately with the hands movements (Eru, 2012).

Imagination further supports the attainment of a broad imaginable space that virtual reality technologies should have, which can then broaden the scope of human cognition after which deficiencies such as dyskinesia. With simulated imagination, the machines will not only reproduce the real environment, but also will arbitrarily conceive virtual environment that is objectively nonexistent or even impossible to exist. The applicability of immersion, imagination and interactivity provides a complete virtual reality system which then ushers in the need to develop a virtual environment as well as a virtual environment processor containing a high-performance computer core, a vision system made of the HMD core, an auditory system made the voice recognition, a voice synthesis and sound localization as the core (Broeren, Lundberg, Molen, Samuelsson-Sunnerhagen, Bellner & Rydmark, 2003).

2.3       Empirical Framework

Owing to some technological, social and economic factors, the continued use of VR has been promoted among many people. The essentials of the VR therapies and rehabilitation will be discussed in other sections of this paper and diagrammatically represented using representations which add up to giving the empirical framework or evidence on the practicality of the virtual reality for rehabilitation. From the empirical view point, there is proof that substantiates the reality behind the application of VR is embodied in many subjects of study apart from rehabilitation in medical facilities (Karageorghis & Terry, 1997). There is important practical significance for the applications of Virtual Reality in medicine. In a virtual environment, students can practically create a virtual human model. This is because the structure of the body’s internal organs can be easily understood by means of a trackball, HMD, and feeling gloves, which is much more effective than the way of using existing textbooks. Scientists can create a virtual laboratory and do virtual surgical training in these laboratories. They can set up a virtual surgical environment, which includes virtual operating tables, virtual surgical lights, virtual surgical tools (such as scalpels, syringes, forceps, etc.), and virtual human models and organs. And with the assistance of HMD and sensory gloves, the user can carry out operation on the virtual mannequin (Broeren, Björkdahl, Pascher & Rydmark, 2002). In medical colleges, students can do anatomies of corpses and various surgical practices in the virtual laboratory. Using this technology, the training costs will be greatly reduced because there is no need for concern regarding the need for specimen, venue and other restrictions. A very high degree of simulation effect can be obtained by some virtual reality systems which are used in medical training, internships and study have, so its advantages and effects are immeasurable and incomparable.

The best empirical application of the VR systems is in rehabilitation training. Where rehabilitation training includes physical rehabilitation and psychological rehabilitation training, which refers to a form of recovery treatment offered to a variety of movement disorders for instance the incoherent actions and moves that are out of control and mental disorders (Eru, 2012). The rehabilitation process targets the improvement of people who can take care of themselves freely in their life after accidents or sicknesses that impacted their movement. Rehabilitation relieves psychological disorder training using the three-dimensional virtual environments. Traditional rehabilitation is time costing and tedious, and its training intensity and effects assessment cannot be evaluated in time, possibly leading to the missing of the best training opportunities. However, the VR rehabilitation training combining three-dimensional virtual and simulation technology can solve this problem with precision. This technology is also good for patients who need psychological rehabilitation, and who lose the movement ability completely. Furthermore the introduction of VR rehabilitation training refers to the training process where the user input actions into computers using devices such as data gloves, motion capture device in order to get visual, auditory or tactile and other sensory feedback from the feedback output device and ultimately achieve the maximum recovery of part or all of his physical function (Bardorfer, Munih, Zupan & Primozic, 2011). This training approach does not only save resources on training but also increase the therapeutic interest of the patient effectively by stimulating the enthusiasm of patients involved in the treatment, the treatment process turns itself from passive to positive way, thus the treatment efficiency is greatly improved.


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