WASHINGTON, D.C.--Some parents play Mozart for their infants, hoping to instill genius, or at least give them a leg up when they start school. While the strategy has been discounted as a path toward early achievement, musicians may have an edge over nonmusicians when distinguishing between speech sounds. The results may help explain how music therapy sometimes aids children struggling with language and reading.
Listening to people speak is more complicated than it might seem. The brain must make out the individual sounds--called phonemes--that make up words. The critical contrasts can be slight: The acoustic difference between the syllables "ba" and "da," for instance, lasts only 40 milliseconds. Trouble with these distinctions may make reading difficult for dyslexic children. But studies have shown that singing and rhythm games improve dyslexic children's spelling and phonological skills.
That led Nadine Gaab of the Massachusetts Institute of Technology in Cambridge to wonder whether music somehow enhances a student's ability to discriminate rapid changes within sound. She and colleagues looked for the answer by rounding up 14 adult musicians who had learned to play an instrument before they were 7 years old and who continued to play at least a few hours each week. They then pitted the speech discrimination abilities of these performers against 14 nonmusicians matched in age, gender, and general language ability. The researchers asked the subjects to listen to pairs of synthesized speech syllables and say whether they were the same, then made the sounds increasingly similar until the listeners could no longer distinguish between them.
Early music exposure appears to make a difference. While musicians and nonmusicians were equally matched when it came to distinguishing pairs of syllables that differed only in frequency, usually perceived as pitch, musicians were more adept when timing was involved. They heard finer differences in the brief gap between consonant and vowel that separates the syllables "ga" and "ka" than nonmusicians. And when both timing and frequency were involved, in the contrast between "ba" and "wa," musicians outperformed nonmusicians by a wide margin. This enhanced ability to correctly categorize speech may be what gives musicians a better memory for words, says Gaab, who presented her work at the Society for Neuroscience meeting this week.
Neuroscientist Robert Zatorre of McGill University in Montreal, Canada, says the results are surprising. "You wouldn't necessarily expect that musicians would be better at speech," he said. Further work is needed, he said, to identify the specific type of musical experience that might lead to better language skills.