Age differences in the use of informative/heuristic communicative functions in young children with and without hearing loss who are learning spoken language.

Previous research has suggested that the normal development of communicative functions proceeds from the directing or "instrumental" types to the informative or "heuristic" types with age. This paper describes a cross-sectional study of communicative function in children with profound hearing loss and children with normal hearing, from ages 12-54 months. The children with hearing loss were learning spoken English as their primary means of communication. The primary purpose of the study was to evaluate whether the pattern of age differences seen in the two groups of children (those with and without normal hearing) are similar patterns that occur at differing chronological ages, or whether they are dissimilar patterns altogether. A second purpose was to examine the relationship between the use of informative/heuristic functions and the acquisition of vocabulary and syntax. The data suggested a somewhat different pattern of communicative function development in children with and without hearing loss. In addition, the use of language for social purposes was closely related to the achievement of traditional language milestones. In both normally hearing children and in those with hearing loss, the correlations between the use of informative-heuristic functions and various measures of language development indicated that the more mature uses of language co-occur with increased frequency of communication, larger vocabulary, and longer utterance length. These results document that when linguistic improvements such as increasing vocabulary size and sentence length occur in deaf children learning spoken English, they are used for appropriate and informative social purposes that are commensurate with their language age.