Advances in Cognition, Education, and Deafness

Input/Output Modalities and Deaf Children's Psycholinguistic Abilities

Input/Output Modalities and Deaf Children's Psycholinguistic Abilities Harry W. Hoemann Ryan D. Tweney The research described in this report explores the psycholinguistic properties of American Sign Language (ASL) and the psycholinguistic abilities of deaf children. Two related questions are addressed. First, are ASL and English equally suitable for deaf children's linguistic, cognitive, and communicative needs? Or is it possible, as some have suggested (Fusfeld 1958; Myklebust 1964), that ASL is too iconic or ideographic to support deaf children's intellectual development? Second, do deaf and hearing children use the same cognitive processes and develop the same psycholinguistic abilities at about the same time and in the same sequence, regardless of the modality of the language they are learning to use? Or is it possible, as some have suggested (Levine 1960; Lewis 1968; Myklebust 1964), that deaf children's linguistic deficiency in English limits their ability to engage in certain kinds of abstract thinking and their development of cognitive and psycholinguistic abilities? Our review is selective; we focus on work in which we have participated. Readers interested in related research are directed to the relevant selections of Bellugi and Studdert-Kennedy (1980), Friedman (1977), Furth (1966), Kavanaugh and Cutting (1975), Klima and Bellugi (1979), and Wilbur (1987). Our data come from five different research areas: translation science, the grammatical structure of ASL, word/sign associations, organization of a subjective lexicon, and categorical coding in short-term memory. The preparation of this manuscript was supported by the Department of Psychology, Bowling Green State University, and by the Bowling Green Press, Inc. 111 112 Language and Cognition TRANSLATION SCIENCE Many observers have been struck by the fact that the lexicon of ASL is relatively iconic: Some signs look like what they mean. Does this feature limit ASL's ability to function as a fully abstract language system? We think not. Only a small percentage of the ASL lexicon is transparent, and many ASL signs in no way resemble their referents (Hoemann 1975). Moreover, metaphoric uses of many signs (HUNGRY and WISH, ERASE and FORGIVE, CLEAN and NICE, TERRIBLE and AWESOME) indicate that the underlying imagery of signs does not impose strict limits on their meanings. We doubt that deaf people are even aware of the imagery that hearing people tend to see in many signs. This area may be worthy of investigation. We are even more reluctant to believe that ASL cannot communicate abstract ideas. If this point were true, propositions involving abstract concepts expressed in English could not be translated into ASL as a target language. However, two back-translation studies, in which English originals were translated into ASL and then back into English by different translators, support the opposite conclusion (Hoemann & Tweney 1973; Tweney & Hoemann 1973a). A comparison of the English original versions with the back-translated versions revealed that the meaning of the original was preserved even when the surface structure was not. This finding is important; if the surface structure had been preserved along with the meaning, one could argue (as did Lewis 1968) that sign languages are effective only when they draw on a spoken language for their structure. The fact that the surface structure could be changed while the meaning was preserved supports the view that ASL has strategies for coding abstract meaning that are different from English. GRAMMATICAL STRUCTURE Several varied studies have confirmed the general point that ASL, like any spoken language, possesses complex grammatical, morphological, and phonemic structure (Klima & Bellugi 1979; Liddell 1980; Stokoe 1960, 1972; Wilbur 1987). More to the point, such structure is functionally available to the deaf user as a carrier of abstract semantic content. Thus, Tweney, Heiman, and Hoemann (1977) demonstrated that ASL grammatical structure serves to offset "noise" in the visual channel just as English grammatical structure serves to offset noise in the acoustic channel. In other words, both ASL and English possess inter-item redundancy in the informational sense. Tweney and Heiman (1977) and Hoemann and Florian (1976) found similar effects in memory: ASL structure, like English structure, can serve as an automatically encodable basis for the enhancement of memory performance. Tweney , Liddell, and Bellugi (1983) showed that sophisticated nonmanual embedding processes in ASL sentences served to structure the perception and memory of complex ASL sentences. Poizner, Bellugi, and Tweney (1980) have shown that formational parameters of ASL (handshape, location, and movement) function Input/Output Modalities and Deaf Children's Psycholinguistic Abilities 113...