Precursors to speech in infancy: The prediction of speech and language disorders

During the canonical stage of infant babbling, infants produce well-formed syllables, often in reduplicated sequences such as "bababa." Although nearl y all infants with normal hearing begin the canonical stage by 10 months of age, a few are delayed, and these infants may be of special interest. Rece nt studies indicate that late onset of canonical babbling may be a predicto r of disorders. A simple screening procedure that focuses on canonical babb ling was used to evaluate over 3400 infants at risk who were about 10 month s of age. Among infants who showed late onset of canonical babbling, fewer than half had been previously diagnosed as having a significant medical pro blem that might have accounted for the delay. A follow-up study indicated t hat infants with delayed canonical babbling had smaller production vocabula ries at 18, 24, and 30 months than did infants in the control group. The re sults suggest that late onset of canonical babbling, a factor that can be m onitored effectively through an interview with a parent, can predict delay in the onset of speech production. (C) 1999 by Elsevier Science Inc.