A clot lodges in an artery supplying blood to the brain, impairing proper circulation and depriving brain tissue of needed blood. Or a blood vessel in the brain ruptures, causing blood to pool in the brain cavity. In either case, the result is a stroke.
For decades, it was believed that once brain cells died they were irretrievably lost—as was any hope of regaining use of a paralyzed limb. Consequently, rehabilitation focused on teaching stroke victims to compensate for lost function by relying on an unaffected limb or by using special feeding utensils, for example.
Although this approach helps stroke victims regain a sense of independence, all too often the affected limbs remain unchallenged. After a while, a patient may give up trying to move the paralyzed arm or leg in a kind of “learned helplessness.”
However, University of Alabama scientists have found that a technique called constraint-induced movement (CIM) therapy can prod the affected part of the brain to rewire itself, making it possible for stroke victims to regain at least partial use of a paralyzed limb.
The researchers restrained the nonparalyzed arms of 13 stroke patients with a splint and a sling, encouraging them to use their weakened arms. The restraints were worn for eight to 10 hours a day for 12 days. On eight of those days, the patients were trained to use the paralyzed arm to carry out increasingly difficult tasks, such as picking up beans one by one. The exercises lasted about six hours a day.
Although CIM therapy can be difficult, the rewards can be significant: The study subjects regained a significant percentage of their lost function in less than two weeks. Six months later, the benefits persisted, and more remarkable, the therapy proved effective even in those who had experienced a stroke several years before the study.