An infant child's cries are his or her way of communicating with the world. However, the baby's cries have more information to communicate beyond saying "I'm hungry," or "I'm tired." The complexity of melody and rhythm within a cry can be an early indicator of a child's prespeech development. A new study compares the cries of 2-month-old infants with cleft lip or palate and those without this condition and finds indications of developmental differences. The authors of the article, published in the May 2011 issue of The Cleft Palate–Craniofacial Journal, sought to objectively analyze melody structure of infants' cries using signal analysis techniques.
The German study compared 11 infants with cleft lip and palate and 10 infants with cleft palate only with a control group of 50 unaffected infants. While there was little difference between the 2 affected groups, researchers found a significant difference in the cries of infants with cleft lip or palate compared to unaffected infants. A simple cry melody consists of a single rising and then falling arc. These become much more complex with age. During the second month of life, healthy infants are displaying complex melodies in more than 50% of their cries. The ability to intentionally segment melodies by brief pauses is an important rhythmic skill that later leads to syllable production. Infants who do not display a certain degree of melody complexity by the second month of life are at a higher risk for poorer language performance 2 years later. Those with less than 45% complex melodies, noted by segmented, nonsegmented, and multiple-arc features, were almost 5 times more likely to develop a language delay. For infants above the 45% threshold, development of a language delay condition could be ruled out with an 89% probability. A number of linguistic delays have been noted among children with orofacial clefts. They have been consistently found to show a higher prevalence of language disorders, phonological ones in particular, than the general population. Some of these can be explained as directly or indirectly related to the cleft. A better understanding of the earliest vocal development could offer new possibilities for fine-tuning primary intervention and individual prespeech development, helping to further improve language outcome in infants with clefts.
(Source: "Cry Melody in 2-Month-Old Infants With and Without Clefts," Cleft Palate–Craniofacial Journal. May 2011, Volume 48, Number 3, published by Allen Press)