Melodic Intonation Therapy Teaches Stroke Victims How to Speak Again
If music is the universal language, it should come as no surprise that music therapy can be a tool to help stroke victims regain their ability to speak. Of the estimated 600,000 to 750,000 adults who have strokes each year, about 20% are left with aphasia, a disorder that renders the patient unable to speak, read, write or understand what other people are saying. One type of aphasia is called non-fluent aphasia or Broca’s aphasia, because the area where the stroke occurred includes Broca’s region, one of the language centers in the brain. Patients with Broca’s aphasia have difficulty saying words, though their comprehension can be normal. For years neurologists and speech language pathologists have noted that many of these patients are able to sing lyrics, even when they have difficulty speaking these same words… an observation that led Gottfried Schlaug, MD, PhD, an associate professor of neurology at Harvard Medical School and staff neurologist at Beth Israel Deaconess Medical Center, to explore the effectiveness of Melodic Intonation Therapy (MIT) on stroke patients with non-fluent aphasia, which revealed brain changes due to the treatment using functional and structural brain imaging.
HOW IT WORKS
A speech therapist uses MIT by teaching a patient to sing simple melodies while tapping out rhythms with the left hand. The tapping is thought to stimulate the right side of the brain, which might be important for articulation, explained Dr. Schlaug.
Although the left side of the brain is commonly believed to be the side of the brain where language is formulated, studies have shown that both sides of the brain actually are involved in vocal production. For most healthy individuals, the left brain is more active, and the right side plays a supportive role — however, since patients with large left brain strokes may only have the option of recovering through the right side, it was reasoned that melodic intonation therapy might be an ideal means to facilitate this recovery process for them.
SINGING THE PRAISES OF MIT
The benefits of MIT have been demonstrated in a series of studies. Dr. Schlaug and his colleagues at Beth Israel Deaconess Medical Center and Harvard Medical School have been tracking the progress of nearly a dozen patients with non-fluent aphasia as they underwent MIT and reported “remarkable results.” Dr. Schlaug found that MIT’s “unique engagement of the right hemisphere” through singing and left-hand tapping resulted in significant improvement in speech compared with the control intervention.
As with any learned skill, the more the patient practices, the better the outcome. For success in regaining speaking skills, patients must practice-practice-practice, says Dr. Schlaug. “Since we are aiming to rewire the stroke patients’ brains, they will have to keep practicing the skills we teach them for a long period of time, probably for the rest of their lives. Being able to speak again or speak more fluently should be well worth the effort.”