The mysteries of the human brain

Many years ago, I was talking to a friend of mine who was a medical student on his neurology rotation.  He related what was, to me, an amazing story.  The patient he saw that day was a fairly young man who had suffered a major stroke, resulting in an almost complete loss of speech (aphasia).  He could still form sentences, but the words were all wrong.  So, instead of saying “Can I have a drink of water,” he’d say “Cow book the drive blanket for tears.”  It was tragic.  What struck my friend, though, was when the doctor in charge asked the patient to sing “Twinkle, twinkle.”  My friend expected to hear nothing, or gibberish.  Instead, the patient sang the song word perfectly — and was able to do so with several other nursery songs.  That’s when I first learned that we store music, including lyrics, in a different part of our brain from language.

Because of my friend’s anecdote, I’ve always been fascinated by the intersection between words and lyrics.  I therefore read with interest a story in today’s New York Times about a singing therapy for aphasic stroke victims:

The technique, called melodic intonation therapy, was developed in 1973 by Dr. Martin Albert and colleagues at the Boston Veterans Affairs Hospital. The aim was to help patients with damage to Broca’s area — the speaking center of the brain, located in its left hemisphere.

These patients still had relatively healthy right hemispheres. And while the left hemisphere is largely responsible for speaking, the right hemisphere is used in understanding language, as well as processing melodies and rhythms.

“You ask yourself, ‘What specifically engages the right hemisphere?’ ” said Dr. Gottfried Schlaug, a neurologist at Beth Israel Deaconess Medical Center in Boston, who studies music’s effect on the brain.

Melodic intonation therapy seems to engage the right hemisphere by asking patients to tap out rhythms and repeat simple melodies. Therapists first work with patients to create sing-song sentences that can be set to familiar tunes, then work on removing the melody to leave behind a more normal speaking pattern.

But relatively little research has been done to understand how this type of therapy affects the brain of a stroke patient.

In a study completed in 2006, Dr. Schlaug and colleagues at Harvard tracked the progress of eight patients with Broca’s aphasia as they underwent 75 sessions of melodic intonation therapy. M.R.I. scans taken when the patients were speaking simple words and phrases showed that activity in the right hemisphere had changed significantly over the course of treatment.

“The combination of melodic intonation and hand-tapping activates a system of the right side of the brain that is always there, but is not typically used for speech,” Dr. Schlaug said.

He recommends melodic intonation therapy for patients who have no meaningful form of speech, but can understand language and have the patience for therapy sessions.

You can read the rest of the story here, including an interview with a stroke victim who re-learned speech through this technique.