Compared with hearing readers, orthographic information and phonological information may play different roles in the word recognition process for hearing-impaired readers. As a communication mode for hearing-impaired readers, sign language may also affect their word recognition process. A large number of studies have examined the activation of orthographic representation, phonological representation, and sign language representation during visual word recognition in hearing-impaired readers. Previous studies have found that hearing-impaired readers could activate stable orthographic representations, but there were inconsistent results in the activation of phonological representations, whereas studies on hearing- impaired readers who primarily use sign language have found that they can activate stable sign language representations. Hearing-impaired readers grow up in a complex language environment, which leads to great individual differences in language experience and reading ability. However, previous works have not clearly identified the effect of language experience and reading ability on the cognitive mechanism of reading in hearing-impaired readers. Continuous attention to this problem will help to provide a reference to guide reading instruction for hearing-impaired readers. This study conducted two semantically related decision tasks to investigate the activation of orthographic, phonological, and sign language representations during Chinese visual word recognition in hearing-impaired college students. Orthographic and phonological representations play an important role in word recognition for hearing readers, but sign language representations are a phenomenon unique to deaf readers. In the current study we investigated the activation of orthographic and phonological representation in Experiment 1 and the activation of sign language representation in Experiment2. To investigate the effects of individual differences, according to their language experience and reading fluency, hearing-impaired college students were divided into deaf college students with oral language experience and higher reading ability (Skilled Oral Deaf, SOD), deaf college students with sign language experience but higher reading ability ( Skilled Sign Deaf, SSD), and deaf college students with sign language experience and lower reading ability (Less-Skilled Sign Deaf, LSSD). The results of Experiment 1 showed that (a) hearing students showed a stable orthographic interference effect, whereas the phonological interference effect was weak. (b) The SOD group and the SSD group showed similar performance. Both showed a stable orthographic interference effect but did not show a significant phonological interference effect. (c) The SSD group and the LSSD group showed similar performance. Both groups showed a stable orthographic interference effect but did not show a phonological interference effect. Experiment 2 found that (a) hearing students did not show a sign language interference effect. (b) The SOD group and the SSD group differed in performance. The SSD group exhibited a sign language interference effect, whereas this effect was absent in the SOD group. ( c) The SSD group performed similarly to the LSSD group. Both groups showed a stable sign language interference effect. Taken together, the following conclusions were drawn from the two studies: ( a) after controlling for reading ability, language experience affected Chinese lexical recognition in deaf college students; lexical representation of oral deaf college students was similar to that of hearing readers., orthographic representations were mainly activated; and the activation of phonological and sign language representations was weak. Deaf college students who used sign language developed a unique cognitive mechanism, and they activated stable orthographic and sign language representations during visual word recognition. (b) After controlling for language experience, reading ability did not affect lexical representation during Chinese word recognition in hearing-impaired college students. (c) Based on the results of this study, combined with the representation and processing models of Chinese word recognition, we attempted to construct a cognitive model of Chinese word recognition for hearing-impaired college readers.
