153ISSN 1473-7175© 2011 Expert Reviews Ltdwww.expert-reviews.com
Editorial
10.1586/ERN.10.201
Can virtual reality offer enriched environments for rehabilitation?Expert Rev. Neurother. 11(2), 153–155 (2011)
“…the advent of new technology, such as virtual reality, allows us the opportunity to manipulate the learning environment and
provide a more intensive learning experience.”
Recent research on the mechanisms of neuroplasticity has led to great advances in our understanding of the adaptive capacity of the nervous system [1]. This, in turn, has led to an increasing interest in how neurological therapeutic interventions can best be delivered to drive neuroplasticity in order to shape recovery after brain injury or disease. Animal and human research has identified some of the key principles of rehabilitation for optimizing recov-ery in many areas, including language, behavior, cognition and sensorimotor function. For sensorimotor recovery, in particular, a major emphasis has been placed on the processes of learning and experience-dependent plasticity [2]. Brain damage alters learning processes because of changes in neuronal and non-neuronal connectivity in reaction to cell death and reorganization. Yet, evidence suggests that the principles of learning, identified in the intact nervous system, may not necessar-ily be the same in individuals with brain damage. Brain damage often affects cogni-tive processes, such as attention and execu-tive function, as well as working memory, which are important for motor learning [3]. For example, attention modifies neu-ral responses in the visual, auditory and somatosensory systems (e.g., [4,5]). Another principle, fundamental to sensorimotor learning in the intact nervous system, is the type of task practice (e.g., repetitive blocked- or varied-task practice). Different
practice paradigms influence immediate changes in motor skills and the ability to retain such changes for a period of time after the end of practice.
Are the same principles described for learning in the intact nervous system applicable after brain damage? In par-tial answer to this question, Cirstea et al. found that individuals with chronic stroke needed to repeat a much larger number of trials of a reaching movement before improvements in movement outcomes, such as movement speed and precision, were obtained [6]. The number of repeti-tions needed for improvements in reach-ing movement to occur varied with stroke severity, such that even individuals with mild poststroke hemi paresis needed to practice twice the number of trials before movement error was reduced. For those with more severe hemiparesis, the num-ber of repetitions was increased several-fold and learning was often incomplete. Other researchers have found that not all types and schedules of feedback may result in beneficial motor outcomes for all stroke survivors. Lesion location appears to affect the individual’s ability to make use of specific types of feedback, such as intrinsic or extrinsic feedback [7,8]. Thus, it is becoming apparent that patients with different lesion types and severity vary in their responses to different types of inter-vention. The question of which patients with brain damage can benefit from which
Mindy F LevinSchool of Physical and Occupational Therapy, McGill University, Montreal, Quebec, Canada and Center for Interdisciplinary Research in Rehabilitation (CRIR), Montreal, Quebec, Canada [email protected]
Keywords: motor learning • motor recovery • plasticity • rehabilitation • technology
THeMed ArTICLe y Stroke
For reprint orders, please contact [email protected]
Exp
ert R
evie
w o
f N
euro
ther
apeu
tics
Dow
nloa
ded
from
info
rmah
ealth
care
.com
by
Ond
okuz
May
is U
niv.
on
11/1
0/14
For
pers
onal
use
onl
y.
Expert Rev. Neurother. 11(2), (2011)154
Editorial
rehabilitation intervention(s) is also now being recognized as a critical one, as our understanding of learning and adapted learn-ing processes progresses. For example, recent research has demon-strated that, when evaluating treatment effectiveness that relies on learning processes, we need to consider not only the mechanisms of synaptic and neuronal processes involved in learning, but also how genetic expression influences these processes in different individuals (see [9]).
Nevertheless, there is agreement that motor recovery after brain damage necessitates that the individual engages in repetitive, inten-sive and salient task practice. These are but three of the ten principles of experience-dependent neural plasticity arrived at by a consensus panel of experts in neurorehabilitation, summarized in a recent paper by Kleim and Jones [2]. Emphasis is placed on the targeted engagement of a specific brain function to avoid its functional deg-radation and to enhance its activity. For example, in animal models of stroke, loss of motor circuitry after ischemic lesions was mini-mized and reorganization in the undamaged cortex was facilitated following intensive practice of skilled reaching [10,11]. An important aspect of rehabilitative training is that the learner has opportunities to meaningfully interact with objects in the environment and to receive salient feedback about their performance to enhance the learning experience. The learner’s level of engagement or motivation is also an integral element for learning to occur through neuroplas-tic mechanisms [10]. Although conventional rehabilitation practice usually includes these key features of motor learning: repetitive and intensive practice, interactive environments, feedback and learner’s motivation, the advent of new technology, such as virtual reality, allows us the opportunity to manipulate the learning environment and provide a more intensive learning experience.
“…there is agreement that motor recovery after brain damage necessitates that the individual
engages in repetitive, intensive and salient task practice.”
Virtual reality is a computer-based technology that provides a multisensory environment with which the user can interact [12]. Several types of virtual reality applications have been developed, ranging from fully immersive 3D cave systems to game-like applications played on computer screens or with robotic assistive devices for motor re-education. Virtual reality systems can use sophisticated equipment, including specialized graphic software and interfaces, such as head-mounted displays and peripheral haptic devices for provision of somatosensory feedback, or simple low-technology applications using webcams, computer screens and joysticks. Applications using virtual reality are also varied, including gait and balance retraining, executive functioning, multitasking, pain management and upper-limb rehabilitation in both adults and children (e.g., [13]).
An important caveat is that the technology itself is far more advanced and varied than the scientific evidence supporting its effectiveness. In addition, the technology is changing so rapidly that even when evidence does appear, it may apply to already obsolete equipment and applications. The rapid evolution of the field is
highlighted by the recent establishment of a consortium of inter-national societies devoted to the development of virtual reality tech-nology and its applications under the umbrella of the International Society for Virtual Rehabilitation [101]. Virtual rehabilitation is still a young field and one that requires a sustained and close dialog between those in industry, academia and clinical practice.
“Virtual reality technology has a great potential to enable us to design individualized and enriched
practice environments that take advantage of the principles of motor learning and neural plasticity to
optimize recovery after brain damage or injury.”We are still at the early stages of gathering evidence of the
effectiveness of various virtual reality applications in rehabilita-tion areas pertaining to children and adults. The first reports published were mainly technical spreadsheets and descriptions of virtual environments and applications. Currently, the evidence for effectiveness of these applications is encouraging, but still not very strong in scientific terms. For children, studies have focused on how well virtual reality interventions may induce playfulness, how much it motivates children to do more exercise, how pleasur-able or acceptable it is and how it impacts motor and visual–per-ceptual skills (for a recent review, see [14]). In adults, in a recent meta-ana lysis of the effectiveness of virtual reality applications for upper-limb rehabilitation in stroke patients by Saposnik and Levin, 12 randomized clinical trials, observational and pre- and post-intervention studies using virtual reality applications were retrieved, ranging from an immersive cave system to a commer-cially available interactive game platform [15]. All of these studies have reported some degree of positive outcomes in each of these areas, but research about the specific attributes of virtual reality leading to good rehabilitation outcomes is still lacking. At this point, it can be concluded that virtual reality interventions are safe and feasible for use with children and adults with neurologi-cal disorders [15]. Virtual reality technology has a great potential to enable us to design individualized and enriched practice envi-ronments that take advantage of the principles of motor learning and neural plasticity to optimize recovery after brain damage or injury. Still, more research is needed before definitive statements about the effectiveness and added value of virtual reality appli-cations, over and above conventional treatment approaches, can be made and guidelines provided about the optimal treatment parameters needed to achieve various treatment goals.
Financial & competing interests disclosureThe author holds a Tier 1 Canada Research Chair in Motor Recovery and Rehabilitation. Research projects are funded by Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Natural Sciences and Engineering Research Council of Canada and the Rehabilitation Research Network of Quebec. The author has no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
No writing assistance was utilized in the production of this manuscript.
Levin
Exp
ert R
evie
w o
f N
euro
ther
apeu
tics
Dow
nloa
ded
from
info
rmah
ealth
care
.com
by
Ond
okuz
May
is U
niv.
on
11/1
0/14
For
pers
onal
use
onl
y.
www.expert-reviews.com 155
Editorial
References1 Plowman EK, Kleim JA. Motor cortex
reorganization across the lifespan. J. Commun. Disord. 43(4), 286–294 (2010).
2 Kleim JA, Jones TA. Principles of experience-dependent neural plasticity: implications for rehabilitation after brain damage. J. Speech Lang. Hear. Res. 51, S225–S239 (2008).
3 Donovan NJ, Kendall DL, Heaton SC, Kwon S, Velozo CA, Duncan PW. Conceptualizing functional cognition in stroke. Neurorehabil. Neural Repair 22(2), 122–135 (2008).
4 Hsiao SS, O’Shaughnessy DM, Johnson KO. Effects of selective attention on spatial form processing in monkey primary and secondary somatosensory cortex. J. Neurophysiol. 70(1), 444–447 (1993).
5 Johansen-Berg H, Lloyd DM. The physiology and psychology of selective attention to touch. Front. Biosci. 5, D894–D904 (2000).
6 Cirstea MC, Ptito A, Levin MF. Arm reaching improvements with short-term practice depend on the severity of the motor deficit in stroke. Exp. Brain Res. 3152, 476–488 (2003).
7 Winstein CJ, Merians AS, Sullivan KJ. Motor learning after unilateral brain damage. Neuropsychologia 37, 975–987 (1999).
8 Boyd LA, Quaney BM, Pohl PS, Winstein CJ. Learning implicitly: effects of task and severity after stroke. Neurorehabil. Neural Repair 21(5), 444–454 (2007).
9 Pearson-Fuhrhop KM, Kleim JA, Cramer SC. Brain plasticity and genetic factors. Top. Stroke Rehabil. 16(4), 282–299 (2009).
10 Nudo RJ, Milliken GW. Reorganization of movement representations in primary motor cortex following focal ischemic infarcts in adult squirrel monkeys. J. Neurophysiol. 75, 2144–2149 (1996).
11 Adkins DL, Boychuk J, Remple MS, Kleim JA. Motor training induces experience-specific patterns of plasticity
across motor cortex and spinal cord. J. Appl. Physiol. 101(6), 1776–1782 (2006).
12 Schultheis MT, Himelstein J, Rizzo AA. Virtual reality and neuropsychology: upgrading the current tools. J. Head Trauma Rehabil. 17, 378–394 (2002).
13 Deutsch JE, Mirelman A. Virtual reality-based approaches to enable walking for people post-stroke. Top. Stroke Rehabil. 14(6), 45–53 (2007).
14 Snider L, Majnemer A, Darsaklis V. Virtual reality as a therapeutic modality for children with cerebral palsy. Dev. Neurorehabil. 13(2), 120–128 (2010).
15 Saposnik G, Levin MF. Virtual reality in stroke rehabilitation: a meta-analysis and implications for clinicians. Stroke (2011) (In press).
Website
101 International Society for Virtual Rehabilitation www.isvr.org/index.html
Can virtual reality offer enriched environments for rehabilitation?
Exp
ert R
evie
w o
f N
euro
ther
apeu
tics
Dow
nloa
ded
from
info
rmah
ealth
care
.com
by
Ond
okuz
May
is U
niv.
on
11/1
0/14
For
pers
onal
use
onl
y.
Recommended
