New technology helps “rewire” the brain

Until recently, if you lost the use of an arm or leg due to a stroke, doctors assumed that the disability was permanent.

Now: Sophisticated imaging tests have shown that the brain can “rewire” itself and compensate for some of the brain damage caused by a stroke (often resulting in paralysis or problems controlling movement of a limb).

This exciting, new understanding of brain physiology means that the estimated 700,000 Americans who suffer a stroke each year will now have a much better chance of regaining their independence.

To learn more about the latest advances in stroke rehabilitation, Bottom Line/Health recently spoke with Joel Stein, MD, a renowned expert in the field and chief medical officer at one of the country’s leading rehabilitation centers.

A “BRAIN ATTACK”

Our body movements are controlled by brain cells called neurons. During a stroke, a blood clot blocks blood supply to an area of the brain (ischemic stroke) or a broken or leaking blood vessel causes bleeding into or around the brain (hemorrhagic stroke). In both cases, neurons die, and areas of the brain that are responsible for movement or other functions do not send and receive information correctly as a result.

Dead brain cells can’t be revived, but the brain’s ability to “rewire” itself — a quality known as plasticity — means that it is possible for new brain connections (also known as pathways) to take over and do the job of the nonfunctioning neurons.

Even though some stroke-induced brain damage is too great to repair, state-of-the-art stroke rehabilitation helps maximize the brain’s power to create new connections and improve control over body movement.

EXERCISE THE BRAIN AND BODY

Supervised physical therapy should begin, if possible, within a week of suffering a stroke. Movement reinforces brain communication pathways — the more you “work” these pathways, the stronger they become and the easier it is to move the body. The goal of exercise after stroke is to practice movements and to help the brain regain as much function as possible.

The best type of physical therapy depends on the stroke survivor’s abilities and on the resources of the rehabilitation facility. The therapies described in this article are usually used for weeks to months (at least three times weekly for one-hour sessions) as part of an overall rehabilitation program that includes occupational therapy and, in some cases, speech therapy. If you or a loved one is recovering from a stroke, talk with your stroke rehabilitation physician — generally a physiatrist (a physician who specializes in rehabilitation medicine) or a neurologist — about how these breakthrough techniques might fit into your program… *

Constraint-Induced Movement Therapy (CIMT). Recommended for: People who have limited use of an arm due to a stroke.

After recovery, stroke survivors often depend on the more functional, “good” arm to perform daily functions. That causes the affected arm to regress and lose even more function. CIMT forces use of the affected arm.

In a typical two-week course of CIMT, the good arm is restrained in a sling or mitt for nearly all waking hours, including during six hours of daily intensive physical therapy. Research shows that CIMT gives lasting improvement in movement and usage and enhances emotional well-being and quality of life.

Robotics. Recommended for: People with partial use of an affected arm or leg who may need help completing movements, such as using eating utensils. Rehabilitation robotics are sophisticated, programmable mechanical exercise devices. For example…

InMotion2 shoulder-elbow robot. With your arm in a brace attached to the arm of a robot, you “play” adaptive video games that require arm movements. The games get progressively more difficult as your abilities improve. They work by encouraging intense repetition of movements, which strengthens brain connections.

Myomo e100 NeuroRobotic System. This assistive elbow brace straps onto the stroke patient’s affected arm. It works by “reading” your muscle signals and then completing the motion — for example, bending your elbow to lift an object — even if you don’t have complete control yet.

Because you perform the full movement (albeit with help), new brain communication pathways are formed, and eventually you may be able to complete the movement without the mechanical brace.

Hocoma Lokomat. This robot helps with walking. You are strapped into a large machine that supports your body and legs. The robot guides your legs as you walk on a treadmill. It works by helping brain cells re-establish a communication pathway that governs walking.

ELECTRICAL STIMULATION

Just as electrical impulses allow cells in your brain and other parts of your body to communicate with one another, the use of electrical stimulation devices may help the brain restore connections.

Limb systems strap onto an affected arm or leg and deliver mild electrical stimulation to the skin to improve motor abilities. Arm stimulation allows you to grab a glass or write with a pencil. Leg stimulation prevents “foot drop” to make walking easier.

Brain systems work by electrically encouraging the brain to rewire itself. The two main techniques are transcranial magnetic stimulation (TMS), which uses a powerful magnetic pulse to stimulate the part of the brain affected by the stroke… and direct electrical current, a noninvasive technique in which a current passes through the skull and into the brain. These brain systems are still being researched, but scientists hope that electrical stimulation might be enough to help connect the circuits that were damaged during a stroke.

*To locate a stroke rehabilitation center near you, contact the Commission on Accreditation of Rehabilitation Facilities (888-281-6531, www.carf.org).