Music and Light
New Therapy for Stroke Patients

Try your hand an interactive demonstration of the rehabilitation process.
The Biofeedback for Rehabilitation project at Arizona State University is helping stroke patients regain arm control.



Between an anthropology museum and a library on Arizona State University’s Tempe campus, a simple yellow-brick building houses more than a million dollars’ worth of state-of-the-art sensing and monitoring equipment. In a large room on the second floor, matte black paint coats almost every speck of the ceiling, walls and floor. Dim light creates a calming feeling. Computers and air-conditioners hum.

Black ceiling-to-floor drapes cut the room in two. On one side a large wood desk faces a 60-inch TV. Speakers and infrared cameras hang at every angle from a metal cage around the desk and TV.

No, this isn’t a set for a sci-fi flick. Rather, it’s where the Arts, Media and Engineering Department (AME) conducts research for its stroke rehabilitation project.

Michelle Smythe
A research participant in Arizona State University’s Arts, Media and Engineering Biofeedback for Recovery Project reaches out his arm as motion sensors track the movement.

Formally known as Biofeedback for Rehabilitation, the project uses music and light to help stroke patients regain motor functions in their partly paralyzed arm, such as reaching and grasping. It also addresses psychological challenges to motor recovery. “The system reduces a patient’s anxiety about doing something wrong,” said project co-director Thanassis Rikakis. “They gain confidence.”

Playing for recovery

Here’s how it works: Three times a week a stroke patient sits at the desk facing the TV screen. Rikakis or an assistant places numerous quarter-size reflectors on her body and the chair. An image, such as a famous painting, appears on the screen and breaks into hundreds of jittery squares (think over-caffeinated puzzle pieces). Simultaneously, soft, harmonious music spills from the speakers.

“My right arm is better now,” the patient said. “I have
more control over it.”

The patient’s goal is to move her arm at a diagonal while keeping her movement steady and not touching the desk. If the movement is smooth (meaning bone joints are in synchrony) and straight (meaning the spatial position of the arm is correct), the fragmented picture pieces align themselves back into the original image on the screen. The music sounds fuller. “The goal is lots of different feedback that’s easily recognizable without being a sensory overload,” said Todd Ingalls, the project’s music composer.

michelle smythe
Professor Rikakis (far left) watches the research subject (middle) reach out his arm as motion sensors track his movement.

But if the patient turns her arm or wrist, leans forward from the torso or uses some other movement to compensate for her impaired ability to reach with her arm, the picture pieces wobble and turn red without forming the complete image. The music becomes discordant. “It’s meant to be fun and motivational, so it’s not a jarring, negative feedback,” Ingalls said.

The whole process feels like a video game, albeit a high-end, research-intensive one. Infrared cameras track the patients’ body movements via the reflectors. Every imaginable aspect is recorded, graphed and monitored by a team of research assistants and advisers. Afterward, the patient and her therapist can see how she performed and compare this session with previous ones to gauge improvement.

Beyond physical therapy

Researchers have found that patients discontinue traditional physical therapy for various reasons, including pain or boredom. “Current physical therapy practices are very repetitive and can be painful,” said Jeffrey Boyd, a graduate research assistant. “The interactive system allows the patient to do the work themselves. It’s more stimulating of the senses and allows patients to relearn how to use the arm.”

When people suffer a stroke, even a mild one, they usually lose some motor control in their arm. Instead of rehabilitating the limb, some patients simply ignore it and accept the limited function. “Often, they can use the limb more than they do. It’s called learned disuse,” said Dr. Richard Herman, a specialist in neurological rehabilitation and a research professor at Arizona State University. “The idea [of the biofeedback project] is to be able to perform a functional task again.”

One stroke patient* said that while the biofeedback therapy was difficult to do at times, the end result was well worth it. “My right arm is better now,” the patient said. “I have more control over it.”

This type of biofeedback rehabilitation is still in development, but early results show promise for more than just therapy. “We’re now monitoring patients afterward to see how their functional recovery is doing,” Rikakis said. That means determining if the patient is really learning how to use her arm again and complete functional tasks instead of simply being trained in the movement.

Smaller and smarter

It takes five or six people at least half an hour to set up and calibrate the system for each therapy session, which is tailored to the patient’s needs. The goal is to develop smaller, user-friendly systems for hospitals and physical therapy clinics, as well as even smaller, smarter systems that could be used at home without a therapist.

Michelle smythe
Professor Rikakis (left) studies the televised playback of the research participant’s motion as a graduate student tracks data on a computer screen.

A home version should be available in summer 2008. “The home system will allow patients to do this therapy every day, which is key,” Rikakis said. “The therapist will receive data electronically from the home system so that the next time the patient comes into the clinic, the therapist knows exactly what has been done.”

Interactive biofeedback research also shows promise in treating other medical conditions, such as Parkinson’s disease. And perhaps not far in the future, the team in the unassuming yellow-brick building might be applying their research to autism and other neurological disorders.

*The patient’s name has been withheld.

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