Effects of early manual instruction on the oral-language development of two deaf children

The speech and language training provided to deaf children at our clinic is done by the Kanazawa Method, which consists of reception and expression training in sign communication and auditory/oral language, as well as written-language training. In our investigation, we analyzed the acquisition of passive and active vocabulary in sign and oral language. The subjects were two children congenitally deaf at the 105 dB level or greater. Recorded-language samples through the age of 54 months were analyzed. Acquisition of sign occurred more quickly than oral-language acquisition. The children's production of active nouns, function words, and "wh-" question words in sign was equivalent to that of hearing peers, and later this proficiency transferred to oral language. These results suggest that early presentation of sign is effective in the acquisition of function words and interrogative sentences, both of which are especially challenging for the Deaf.