SOURCES: Devin McAuley, Ph.D., professor, psychology, Michigan State University, East Lansing, Mich.; Heather Grossman, Ph.D., clinical director, American Institute for Stuttering, New York City; April 13, 2015, Brain & Language, online
WEDNESDAY, May 27, 2015 (HealthDay News) -- Children who stutter may have difficulty perceiving musical rhythms, a small study suggests.
Researchers say the findings could offer some clues to the origins of the speech problem -- and even hint at potential therapies.
The study, reported online recently in the journal Brain & Language, involved 17 children with stuttering and 17 without. The investigators found that kids with the speech disorder tended to have trouble distinguishing drumbeat patterns during a computer game.
Exactly what it all means is not clear. "But our hypothesis is, children with stuttering have difficulty with internal rhythm generation," said researcher Devin McAuley, a professor of psychology at Michigan State University, in East Lansing.
That's important, he explained, because our ability to keep a rhythm is one of the keys to speaking fluently.
However, the study does not prove that problems with perceiving rhythm actually cause stuttering, McAuley said.
Heather Grossman, clinical director of the American Institute for Stuttering, in New York City, emphasized that point.
Difficulty with perceiving rhythm could be something that commonly goes along with stuttering and is caused by "something more central in the brain," Grossman said.
It's also possible that the stuttering comes first. When a child starts stuttering, Grossman explained, the brain organizes around the habit. "Differences in rhythm perception might be a byproduct of that," she said.
Around 5 percent of all children stutter at some point in their lives -- usually beginning between the ages of 2 and 5, according to the U.S. National Institute on Deafness and Other Communication Disorders. Most kids outgrow the problem, with only about 1 percent of all adults affected by persistent stuttering.
At one time, stuttering was viewed as an emotional problem, Grossman said. But researchers now know that children who stutter show differences in how their brains process language.
Genetics is thought to play an important role, since stuttering tends to run in families, Grossman added.
Still, scientists do not completely understand the mechanisms behind stuttering. And the new study, McAuley said, appears to be the first to find that kids who stutter can have problems perceiving musical beats.
The findings are based on 34 children between the ages of 6 and 11. McAuley's team had each child play a computer game where a drummer would play a standard rhythm twice; then a second drummer would enter the scene and either play that same rhythm or a different one. The kids had to indicate whether that third rhythm matched or differed from the first two.
"Children who stuttered did much worse," McAuley said. The kids also took hearing, language and IQ tests -- none of which accounted for the differences in rhythm perception, he explained.
According to McAuley, it's plausible that problems with rhythm-keeping contribute to stuttering. There's evidence, he said, that people with stuttering have "less connectivity" in a brain network known to be involved in rhythm perception -- though, again, it's not clear that the connectivity issue causes stuttering.
"At this point, more studies need to be done," McAuley said. But, he added, the findings raise the possibility that "rhythm training" -- including through music -- could help some kids with stuttering.
Grossman cautioned against making that leap, however. "I think studies like this are interesting because they give us more proof that there really are brain differences in children who stutter," she said.
But, she added, "You can't assume there's clinical significance in those differences. I think it's unlikely that training in rhythm perception will help with stuttering."
Still, Grossman said, if kids enjoy music lessons and gain confidence from them, that self-esteem could help them with managing their stuttering.
The American Speech-Language-Hearing Association has more on stuttering.