Researching the "Science Behind Sound" / Scientific Frontline®

Researching the "Science Behind Sound"

Thursday, February 7, 2008

MU Researcher Analyzes the Physiology of Singers to Help People with Chronic Vocal Problems

Video 1: If the lung pressure is really high and air flow is really low, they can tell that the problem is somewhere at the valve level or the vocal chord level and they can pinpoint that kind of problem. And once we know the source of the problem, we can correct that with different vocal techniques or voice therapy techniques.

Video 2: People with Parkinson´s have issues with vocal projection and loudness because their muscle power goes down as they get into the disease. And these exercises which work on breathing and vocal aspects of voice production can help them in improving their vocal projection in terms of improving vocal loudness. And regular practice may help them in getting a louder voice even though they get into the Parkinson´s disease.

Credit: University of Missouri / Nandhu Radhakrishnan

Voice production is much more complex than opening the mouth and letting out a sound. Some singers sound good enough to compete on American Idol; others can’t carry a tune and some people deal with even more problematic issues such as chronic vocal problems. Nandhu Radhakrishnan is researching the mechanics of making music at the Laryngeal Physiology Lab he created at the University of Missouri with a room full of tubes, wires, computers and instruments.

Radhakrishnan plans to explain scientifically what great singers do physiologically, and using that knowledge, create therapy for people who have chronic voice problems due to health issues. He also hopes to help other singers sing better and teach people who use their voices professionally – such as teachers – how to do so without harming their voices over time.

Radhakrishnan uses a set of non-invasive instruments – a band around a person’s neck and another mouthpiece to speak into – to record physically how individuals make themselves heard. Different organs and muscles that constitute someone’s voice, such as the lungs, larynx, vocal tract and articulators (lips, tongue, palate) all work together to produce sound.

Instruments in the lab can take voice measurements at a multi-signal level and display exactly which organ or muscle is working and at what level when someone speaks or sings. If someone has an uncommonly weak voice, the lab will be able to pinpoint the problem, such as someone not providing enough air pressure from the lungs. Not every person uses organs and muscles to produce sound in the same way.

“If the lung pressure is really high and air flow is very low, we can tell that the problem is somewhere at the valve level or the vocal chord level,” said Radhakrishnan, assistant professor of communication science and disorders in the MU School of Health Professions. “Once we know the source of the problem, we can correct it with different voice therapy techniques.”

Producing sound is actually a very intricate process utilizing several systems of the body. Lung pressure is a major contributor to the way someone’s voice sounds. Lung pressure can change with volume. A softer voice would have less lung pressure and as a voice becomes louder, more pressure must be put on the lungs to increase air flow.

“People with Parkinson’s disease have issues with vocal projection and loudness because their muscle power decreases as the disease progresses,” Radhakrishnan said. “When we can see physiologically how a great voice works, then we can create exercises to improve breathing and vocal aspects of voice production for people with vocal problems. Regular practice may help people speak in a louder voice and overcome vocal issues despite the progression of Parkinson’s disease.”

Source: University of Missouri