CLASSIFICATION SKILLS IN NORMALLY HEARING/ACHIEVING, ORAL DEAF, AND LANGUAGE IMPAIRED PRESCHOOLERS: A STUDY IN LANGUAGE AND CONCEPTUAL THOUGHT

This study was designed to examine the classification skills of oral deaf, receptive language impaired, and normally hearing/achieving preschoolers in order to investigate two hypotheses. The first is that language plays a differential role in the development of concepts depending on the level of abstraction at which the categories are formed. This was examined by comparing the categorization and related language skills of deaf and normally hearing children since the only significant difference between these groups was their language competence. The second hypothesis is that a conceptual deficit exists in children with severe receptive language impairments, and that this deficit is not the result of poor language skills. This was examined by analyzing the classification skills of oral deaf and language impaired preschoolers. If the latter group performed more poorly than the deaf subjects, language problems could be ruled out as the cause of the poorer performance, since the deaf children presented with a more severe language deficiency.;Results indicated that the differences between the categorization skills of the deaf and normally hearing children on Trial 1 were not significant at the perceptual or basic levels, but were significant at the superordinate level. This finding implies that language is a factor in the acquisition of superordinate level concepts. This was further supported by a significant correlation between superordinate level classification performance and labeling. No correlation was found at the basic level.;The language impaired children performed more poorly than the oral deaf children on most of the classification tasks. This lends support to a cognitive hypothesis of language impairment. Difficulty in classification may be one indication that language impaired children present with a more general deficiency in the area of representational behavior.;Subjects included thirteen receptive language impaired, twenty oral deaf, and twenty normally hearing/achieving preschoolers. The categorization task was composed of three conceptual levels--perceptual, basic, and superordinate--each containing two tasks. All tasks were composed of two free sorting trials, separated by a structured sorting procedure. Following the final trial, expressive and receptive knowledge of the category labels was tested.