Babies’ sound path to language skills

Scientists have demonstrated for the first time that 6-month-olds who perform well on a test of budding speech perception exhibit better language development as toddlers than do those who score poorly on the same test.

SAY WHAT? Six-month-olds who stumble on a sound-perception test may face future language problems. S. Norcross

The test may be able to identify infants headed for various language difficulties, suggest Feng-Ming Tsao of National Taiwan University in Taipei and her colleagues.

The researchers evaluated 14 boys and 14 girls, all 6 months of age, from English-speaking families in the Seattle area. Tsao’s team established how many trials it took for each baby to begin turning his or her head toward a change in the sound coming from a loudspeaker. A voice repeatedly pronounced the sound “u”, as in fun, but would briefly change the sound to “y,” as in fly. To draw attention to the change, a mechanical bear above the loudspeaker pounded a drum for a few seconds immediately after every vowel change.

Half of the babies learned to discern the vowel change within 10 trials and almost always recognized the sound shift in further trials. At 13, 16, and 24 months of age, they scored higher on age-appropriate vocabulary and grammar tests than did children who hadn’t discerned the sound change as quickly, the investigators report in the July-Aug. Child Development.

Bruce Bower has written about the behavioral sciences for Science News since 1984. He writes about psychology, anthropology, archaeology and mental health issues.