May 31, 2006
Symposium looks at therapeutic benefits of musical rhythm
By Emily Saarman
Rhythmic music may change brain function and treat a range of neurological conditions, including attention deficit disorder and depression, suggested scientists who gathered with ethnomusicologists and musicians at Stanford's Center for Computer Research in Music and Acoustics May 13. The diverse group came together for the one-day symposium, "Brainwave Entrainment to External Rhythmic Stimuli: Interdisciplinary Research and Clinical Perspectives," to share ideas that push the boundaries of our understanding of the human musical experience.
Musicians and mystics have long recognized the power of rhythmic music. Ritual drumming and rhythmic prayer are found in cultures throughout the world and are used in religious ceremonies to induce trance states. But since the counterculture movement of the 1960s, scientists have shied away from investigating the almost mystical implications of musical rhythm, said symposium organizer Gabe Turow, a visiting scholar in the Department of Music.
Recent interest in sleep, meditation and hypnosis research has spurred scientists to take a closer look at music. A small but growing body of scientific evidence suggests that music and other rhythmic stimuli can alter mental states in predictable ways and even heal damaged brains.
"I think we've started using the right words to talk about these experiences, words that kept everyone comfortable," Turow said.
Devices called electroencephalographs (EEGs) measure the electrical impulses in the brain. Although EEG measurements cannot clearly discern spatial patterns, they resolve the dominant frequencies of brainwave activity that are associated with conscious states including concentration, anxiety and sleep.
"There is a growing body of neuroscientists who support the theory that if there's a physical correlate of conscious experience, it has to be happening in the brainwaves. It seems to be the only thing in your head that changes rapidly enough to explain real-time changes in consciousness," Turow said.
Music with a strong beat stimulates the brain and ultimately causes brainwaves to resonate in time with the rhythm, research has shown. Slow beats encourage the slow brainwaves that are associated with hypnotic or meditative states. Faster beats may encourage more alert and concentrated thinking.
Studies of rhythms and the brain have shown that a combination of rhythmic light and sound stimulation has the greatest effect on brainwave frequency, although sound alone can change brain activity. This helps explain the significance of rhythmic sound in religious ceremonies.
"It's too easy to forget how fundamental rhythm is in so many things and how important musical rhythm can be," said symposium participant Patrick Suppes, the Lucie Stern Professor of Philosophy, Emeritus, at Stanford, who studies brainwaves and language cognition.
Harold Russell, a clinical psychologist and adjunct research professor in the Department of Gerontology and Health Promotion at the University of Texas Medical Branch at Galveston, used rhythmic light and sound stimulation to treat ADD (attention deficit disorder) in elementary and middle school boys. His studies found that rhythmic stimuli that sped up brainwaves in subjects increased concentration in ways similar to ADD medications such as Ritalin and Adderall. Following a series of 20-minute treatment sessions administered over several months, the children made lasting gains in concentration and performance on IQ tests and had a notable reduction in behavioral problems compared to the control group, Russell said.
"For most of us, the brain is locked into a particular level of functioning," the psychologist said. "If we ultimately speed up or slow down the brainwave activity, then it becomes much easier for the brain to shift its speed as needed."
Russell, whose study was funded by the U.S. Department of Education and included 40 experimental subjects, hopes to earn approval from the Food and Drug Administration to use the brainwave entrainment device as a treatment for ADD. The device uses an EEG to read brainwaves and then presents rhythmic light and sound stimuli through special eyeglasses and headphones at a slightly higher frequency than the brain's natural rhythm.
Thomas Budzynski, an affiliate professor of psychology at the University of Washington, conducted similar experiments with a small group of underachieving college students at Western Washington University. He found that rhythmic light and sound therapy helped students achieve a significant improvement in their grades.
Budzynski also found that rhythmic therapy could improve cognitive functioning in some elderly people by increasing blood flow throughout the brain. "The brain tends to groove on novel stimuli," Budzynski explained. "When a novel stimulus is applied to the brain, the brain lights up and cerebral blood flow increases." To maintain the high blood flow, Budzynski used a random alternation of rhythmic lights and sounds to stimulate the brains of elderly people. The result: Many of the seniors improved performance on an array of cognitive tests.
Anecdotal evidence suggests that this increased blood flow also could help victims of brain damage regain cognitive function. Russell used brainwave entrainment to help his wife recover from a severe stroke. "One day she told me the fog went away," he said.
Neuroscientists caution that there is still a great deal to learn. "While these things are intriguing, we haven't worked out the perceptual pathways in the brain for processing hearing as well as we have for visual and sensory perception," said David Spiegel, the Jack, Samuel and Lulu Willson Professor in Medicine at Stanford. "Figuring out this entrainment is complicated by the fact that we need to learn more in general about how the brain processes auditory stimuli."
Most music combines many different frequencies that cause a complex set of reactions in the brain, but researchers say specific pieces of music could enhance concentration or promote relaxation. "If we can get some reliable evidence from neuroscientists that music therapy works, music is cheap and nearly anybody can get access to it," Russell said.
Brainwave entrainment research is still in its infancy, but advocates hope that it may prove a cheap, safe and effective way to treat a variety of neurological disorders from depression to ADD and even prove invaluable in repairing brain damage.
"We may be sitting on one of the most widely available and cost effective therapeutic modalities that ever existed," Turow said. "Systematically, this could be like taking a pill. Listening to music seems to be able to change brain functioning to the same extent as medication, in many circumstances."
Jonathan Berger, chair of the Stanford Department of Music, said he was thrilled with the free flow of ideas at the symposium. "There was no question by the end of the day that this symposium is going to become a regular feature at Stanford," he said. "I'm pretty confident that this will lead to a new research lab here." Berger also plans to produce a book based on the research presented at the symposium.
Emily Saarman is a science-writing intern at Stanford News Service.
Science-writing intern Emily Saarman wrote this release.