The surgical state of the art for treating voice disorders has advanced greatly in recent years. But the way doctors try to determine what causes some people to develop voice disorders is still decidedly low-tech.
"We ask people how they use their voices," says speech-language pathologist and NIDCD-grantee Robert Hillman, Ph.D., "but the problem is, people are really bad historians when it comes to voice use. We have data that shows people tend to be off on average 150 to 200 percent when simply trying to estimate how much they use their voices during a typical day."
Dr. Hillman and his team at Massachusetts General Hospital have developed a mobile monitoring device that relies on smartphone technology to gather a week's worth of talking, singing, yelling—whatever it is people do with their voices.
The device that Dr. Hillman and his team have developed uses a small receiver the size of a dime (called an accelerometer), attached with double-sided sticky tape to the base of the throat, which captures the vibrations that are transmitted from the larynx through the skin. "The goal is to make it as unobtrusive as possible," says Dr. Hillman, "because you want people to be doing things the way they normally do them. The impact has to be minimal." In fact, an earlier version of the device was so unobtrusive that singer Steven Tyler wore it during an Aerosmith concert to document the vocal extremes of rock-and-roll singing.
Once the data are downloaded, a custom-designed software program analyzes the strength and frequency of the vibrations to produce a graph that shows daily voice usage in terms of amount, volume, and pitch.
One of the goals of the monitoring device is to be able to use the data to begin to make some correlations between patterns of voice use and the risk for a vocal disorder. What is normal and what is abnormal voice use? Are there certain ways of using the voice that can cause particular problems? A future feature, when the device goes into clinical testing, will be the addition of a feedback method, such as a buzzer or vibration, to tell the wearer when he is using his voice incorrectly.
"Voice therapy is like any kind of behavior change therapy," says Dr. Hillman. "People will do what we tell them to do when they're in front of us, but maybe not when they're not being watched. Highly habituated vocal habits are hard to break." The feedback device could act like a virtual speech-language pathologist, reminding the patient when she falls back on old habits and giving her a gentle nudge to try on the new ones.