Rehabilitation therapies for stroke survivors provide a means for individuals to move, act or speak more successfully. Physical therapy, occupational therapy and speech therapy all focus on overt behaviors. The use of games to retrain the brain is more recent and is related to our scientific and technological advances
In 1996, neuorologist Dr. Vilayanur S.Ramachandran and colleagues asked amputees to use a virtual realty box (a mirror placed at the mid-line) to experience the reflection of their missing limb. For example, a person with an amputated left limb would place their right limb in front of the mirror and the result was the reflection of the left limb moving about in space. One of the most intriguing results was that several patients experiencing phantom limb pain commanded the brain to unclench the fist of the missing limb by observing a reflection of the limb doing so. When the brain watched the simulated fist unclench, the phantom limb pain was removed.
Since Ramachandran's first published study, the so-called "mirror box" has been used in several research studies as a strategy towards functional recovery in stroke survivors. For example, in a 2003 study reported in "Archives of Physical Medicine & Rehabilitation," a mirror box was used along with imagined movement with chronic stage stroke survivors to provide a means to provide good examples of movement for the brain to practice movement by the impaired limb. The 4-week protocol included simulated practice on a variety of simple and complex action sequences. Even though participants were in the chronic stage (more than 1-year post stroke) and the intervention involved no physical practice, gains in actual performance of the impaired limb were seen following the simulation practice.
The Virtual World of Wii
A higher-tech version of virtual realty is offered from the Nintendo Wii system. Individuals sign in as an avatar that reflects their size and stature and play a variety of sports.
In a 2009, researchers at University of Queensland in Australia reported that experience with the Wii Fit resulted in an immediate effect on balance and strength. In 2010, St. Michael's Hospital In Toronto is completing a clinical trial assessing the improvement in performance of stroke survivors. Patients assigned to the Wii group will receive an intensive program consisting of eight 60-minute Wii gaming sessions over a 14-day period.
There are also a few case studies that have reported on the value of using the virtual world of Wii to improve motor performance. For example, a study published in "Physical Therapy" in 2008 reported on an adolescent with cerebral palsy who participated in training sessions using Wii sports games including boxing, tennis, bowling and golf. Improvements in visual-perceptual processing, postural control and functional mobility were measured after the training and positive outcomes were found at the impairment and functional levels.
While mirror reflection can fool the brain into thinking a limb is present and working fine, the Wii fools the brain into thinking the person is operating within a completely different environment.
The most technological brain games for stroke rehabilitation use robots. Several groups of researchers are developing robotic devices and protocols for their use. Many of the devices are specific to arm movement. In a 2008 study reported in the journal "Brain," chronic stage stroke survivors received three weeks of therapy with a hand-wrist robot that would provide reaching assistance when it was needed. For example, the robot might move a hand more quickly or accurately to a moving target. Following this training there were two important effects. First, participants who received robotic assistance in all sessions (as opposed to just half of them) showed the greatest functional gains. Second, brain scanning with MRI revealed increased sensorimotor cortex activation across the period of therapy demonstrating that work with the robot induced brain changes.
One downside to the use of robots is that access is relatively limited. Typically, use is restricted to persons participating in research in a rehabilitation lab or receiving treatment at a clinic housed within a medical research environment.