No Idol advice about what singing can do to your vocal cords

Listen up, all you American Idol/Hannah Montana wannabes. If not done right, singing pop music can can permanently damage fragile teenage vocal chords.

And unfortunately, new research suggests it's often not done right. Just take a gander at the American Idol castoffs on the audition shows. There's a whole lot of shrieking going on, says Celia Hooper, who used clips from the show when she taught a course on voice disorders.

Cooper, a professor of communications sciences and disorders at the University of North Carolina-Greensboro, and grad students Nathan Waller and Beverly Vaughn wanted to see exactly what was going on in the throats of adolescent singers. So they brought 20 middle and high school students into their lab and asked them to sing opera, gospel and a pop tune: "Tomorrow" from the Broadway show "Annie."

The researchers watched the singers' vocal cords in action with a camera scope and, via the wonders of computer technology, visualized and measured 22 features--such as "roughness" or "screechiness"--of each voice during each song. They had expected that the gospel song would prove to be most stressful on the vocal cords, but "Tomorrow" won that title. Hooper explained to me that gospel as sung by a school chorus might not be as intense as gospel sung in church, "where you would really let it rip."

Hooper hasn't had time to watch much "Idol" this season. But she notes that previous winners Kelly Clarkson and Fantasia both have "rough" singing voices suggestive of strained vocal cords. As far as this year's finalists, Brooke White, who was voted off last week, sounded the roughest to Hooper.

"They're OK now because they're young," Hooper says. "If they plan to have a long career, they need voice lessons from a singing teacher." If belters don't learn proper technique, she says, they can end up losing the ability to hit high notes and turn up the volume.

Fortunately, Hooper says, music education majors these days take anatomy and physiology, so they can train young students how to sing without screwing up their vocal cords.

Of course, she notes, Rod Stewart lost his high notes long ago because of vocal stress and the resulting nodules on his cords, and look where it got him.