The music that makes the foot tap, the fingers snap and the pulse quicken stirs the brain at its most fundamental levels, suggesting that scientists one day may be able to retune damaged minds by exploiting rhythm, harmony and melody, according to new research.
Exploring the neurobiology of music, researchers
discovered direct evidence that music stimulates specific regions of the brain responsible for memory, motor control, timing and language. For the first time, researchers also have located specific areas of mental activity linked to emotional responses to music.
In the long run, music could retool brains afflicted with a variety of emotional disorders or neurological diseases, the researchers said.
"That's our goal," said neuroscientist Anne Blood, who conducted the study at McGill University in Montreal.
"You can activate different parts of the brain, depending on what music you listen to. So music can stimulate parts of the brain that are underactive in these disorders. Over time, we could retrain the brain in these disorders."
The newest findings, presented this week at a meeting of the Society for Neuroscience in Los Angeles, underscore how music--as an almost universal language of mood, emotion and desire--orchestrates a wide variety of neural systems to cast its evocative spell.
"Undeniably, there is a biology of music," said Harvard University Medical School neurobiologist Mark Jude Tramo. "There is no question that there is specialization within the human brain for the processing of music.
Music is biologically part of human life, just as music is aesthetically part of human life."
In a series of new studies made public Sunday, researchers found that the brain:
*Responds directly to harmony. Using a medical PET scanner to monitor changes in neural activity,
neuroscientists at McGill discovered that different parts of the brain involved in emotion are activated depending on whether the music is pleasant or dissonant. "Everyone knows music can produce powerful emotional effects. This suggests different emotions are represented in different parts of the brain," said Blood.
*Interprets written musical notes and scores in a special area on the brain's right side. That region corresponds to an area on the opposite side of the brain known to handle written words and letters. So, in studying the brains of expert musicians, researchers uncovered an anatomical link between music and language. "We are guessing (the area) is involved in the visual processing of the score itself," said Lawrence Parsons at the University of Texas, San Antonio.
*Grows in response to musical training. In a study of classically trained musicians, researchers at Beth Israel Deaconess Medical Center in Boston discovered that male musicians have significantly larger brains than men who have not had extensive musical training. The cerebellum, which contains some 70 percent of the brain's neurons, was about 5 percent larger in expert male musicians.
Researchers, however, found no such size increase in the brains of female musicians, but said they may not have studied enough women to be certain.
"Musicians are not just born with these differences," said Dr. Gottfried Schlaug, the neurologist who conducted the research. The cerebellum grows as a result of the constant practice of the virtuoso motor skills needed to play an instrument, he said.
Overall, music seems to involve the brain at almost every level.
Even allowing for cultural differences in musical tastes, the researchers found evidence of music's remarkable power to affect neural activity no matter where they looked in the brain.
"We find that harmony, melody and rhythm had distinct patterns of brain activity. They involved both the right and left sides of the brain," Parsons said.
The scientists said the new research could help the clinical practice of neurology, including cognitive rehabilitation. As a therapeutic tool, for example, some doctors today already use music to help rehabilitate stroke patients. Surprisingly, some stroke patients who have lost their ability to speak retain their ability to sing, and that opens an avenue for therapists to retrain the brain's speech centers.
"Patients sing what they want to say and some improve their fluency," Parsons said.