ABSTRACT
Prelingual profound deafness not only affects oral language and internal cognitive coding mechanisms, but presents an unusual and unique perspective on psychological and social development in both children and adults. As we have already seen, prelingually deaf individuals usually have normal nonverbal intelligence (Vernon, 1968), have the capacity to handle problems in symbolic logic (Furth, 1966), and develop elaborated conceptual models of their social environment (Gordon, 1977). Nevertheless, their vocational and educational achievements are poor, and the majority fail to acquire speech and lipreading skills sufficient to enable them to interact easily with hearing persons using this method of communication (Lewis, 1968; Mindel & Vernon, 1971). Their average level of competence in English rarely exceeds that of hearing 9-year-olds (Denmark et al., 1979; DiFrancesca, 1972; Myklebust, 1964; Rodda, 1970) only a very small minority gain entry to university; and the adult deaf population is characteristically employed in unskilled and manual work (Schein & Delk, 1974).
