Adi-Bensaid, L. 1, 2 , Tubul-Lavy, G. 1, 3 & Ben-David, A. 4, 5
1 Department of Communication Sciences and Disorders, Ono Academic College, Israel
2 Speech and Hearing Center Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
3 Department of Special Education, Achva Academic College, Israel
4 Department of Communication Disorders, Hadassah Academic College, Israel
5 Department of Communication Disorders, Tel-Aviv University, Israel
Recent studies show the importance of the input in the process of language development. Motherese, baby-talk, Infant-directed Speech (IDS) and Child-Directed Speech (CDS) are terms that refer to special characteristics that exist in the speech that parents display to infants, that differ in key ways from Adult-Directed Speech (ADS). These unique characteristics were described for all language components. Such characteristics may include: shorter and less complex sentences, more restricted vocabulary, a slower rate of speech, a higher fundamental frequency and repetitive utterances (Ferguson, 2004; Owens, 2008). It is assumed that these modifications are designed to facilitate language acquisition and to withdraw the infant's attention to the adult speech. The purpose of the present study was to describe the parents' use of content words in Hebrew-CDS at different stages of language development. The words were classified into six lexical categories: nouns, verbs, adjectives, adverbs, prepositions and pronouns. Participants included 55 parents to children at different stages of language development: a) early pre-verbal, b) late pre-verbal, c) single words and d) early grammar. Children's age range was 5.5-33 months. Forty five minute parent-child-dyads were videotaped at the child's home during eating, bathing, playing, dressing or diaper changing activities. For the purpose of this study, a ten minute randomly selected sample, was transcribed and analyzed both quantitatively and qualitatively. The findings reveal that there are some significant differences in the use of content words in CDS throughout the different developmental stages. While there was a significant decrease in the number of tokens (amount of words per session) with child's age, there was a significant increase in the type of words (diversity of content words) with age. Thus, parents of infants at the early period of the pre-verbal stage used fewer nouns, verbs, pronouns, adjectives and prepositions compared to the following stages.