As a part of this issue’s focus on innovation, we spoke with Edward Taub, a medical researcher who has played a leading role in some of the most significant breakthroughs in brain science in more than four decades.
Taub’s early research, from 1959 to 1980, based on work with monkeys, showed that the brain plays a direct role in body movement, rather than being limited to the neuronal signals of the “reflex arc, ” which had been the common understanding in neuroscience for the first 70 years of the 20th century.
In 1987, Taub moved to the University of Alabama at Birmingham and focused on the area of stroke recovery, developing Constraint-Induced Movement therapy (CI therapy). That work also made major breakthroughs in the area of neuroplasticity, by demonstrating how the brain can adapt and repair itself after an injury.
The American Stroke Association has said his work is “at the forefront of a revolution.” In 2007, the Society for Neuroscience called his work “one of the top 10 translational neuroscience accomplishments of the 20th century.”
Taub is a university professor in the department of psychology at UAB and is the director of the CI Therapy Research Group and Taub Training Clinic. The clinic treats patients from around the world, and application of its therapy has expanded to include rehabilitation after stroke, traumatic brain injury, cerebral palsy in young children, multiple sclerosis and other neurological injuries.
How did your work transition from laboratory research to therapy with human patients?
In developing a therapy based on our research we used two components derived from my primate research: restraint of the good limb and the other was training the affected limb. After a period of time — this was after I came to UAB — I said, “Let’s try it. What do we have to lose?” We worked with patients who were severely disabled after brain injury. We later gave the technique the name Constraint-Induced (CI) therapy or CI therapy, where constraint refers to both the restraint of the stronger limb but also the training given to the impaired arm.
How did your therapy work influence the understanding of neuroplasticity?
When we published our first paper, in 1993, it got a fair amount of attention from the leaders in the field, because the results were very clear and dramatically large — a very substantial rehabilitation of movement. But the vast majority of people in the rehab community — the physiatrists, physical therapists and occupational therapists — ignored it. Then I started going to Germany three months a year and started to do research with a group of colleagues influenced by the seminal findings of Dr. Michael Merzenich, who first demonstrated two kinds of brain plasticity. I had originally gone to Germany to set up CI therapy clinics, which we did at four university hospitals. But while doing this I also started doing research with humans on neuroplasticity after arm amputation. Since we had set up these clinics, and patients were receiving CI therapy, I thought that it would be of value to look at what was happening before and after treatment, to see if CI therapy was producing a change in the brain. So this work stands at the crossroads of the brain and behavior.
Did the idea of neuroplasticity make more of a media splash than your CI therapy?
The focal article published in 2000 in the journal Stroke, showed that after stroke but before CI therapy, the part of the brain primarily responsible for movement of the arm affected by the stroke, the area of the motor cortex representing the arm, shrank by half. This was presumably due to the fact that the person stopped using the arm as a result of the stroke. We found that, as a result of CI therapy, there was a very large increase in the ability to use that arm in life situations. At the same time, we found a correspondingly large increase in the size of the motor hand area. It had doubled and was back to normal size. When that paper hit the journal Stroke, it caused a large flurry of interest, in publications like the New York Times, Time and Newsweek and virtually every newspaper in the country.
After that there was an exponential increase in the amount of interest in CI therapy. It took this neuroplastic change in the brain to convince people. Since then, half a dozen additional articles have been published showing that not only the size of the hand representation increases in the brain but the amount of gray matter also increases.
Describe some of the more recent developments in CI therapy.
Since CI was developed, we have modified the technique and applied it to many conditions other than stroke. It has been equally effective with traumatic brain injuries that involve movement deficits in the extremities, with MS patients and with children with cerebral palsy. We have an active clinic at Children’s of Alabama that offers CI therapy on an outpatient basis to children with motor impairment due to cerebral palsy. We have many patients who come from all over the country and all over the world. We have a clinic at UAB for adults. Interestingly, MS is a degenerative disease that is unrelentingly progressive; you just go down a downhill slope. After CI therapy, a patient’s condition does get worse, but not in the part of the body that we train, and that persists. We have reversed the disease process in movement in the affected part of the body that we train, and that persists. We have also modified the technique and applied it to aphasia after stroke, speech problems, with equally good results as we get with movement.
Most recently we have been working with patients with spinal cord injuries high in the neck. Our patients are said to have high tetraplegia; they are paralyzed from the neck down, but the spinal cord is not completely cut in two or transected. Although they are paralyzed from the neck down with no overt movement, there is still some connection between the brain and the extremities. We use EMG biofeedback, a technique in which we place sensors on the surface of the skin above the muscles of the arm and then ask the patients to move. Ultimately, in the two patients we have worked with to date, we’ve gotten overt movement.
Chris McFadyen is the editorial director of Business Alabama
Interview by Chris McFadyen