American Sign Language syntactic and narrative comprehension in skilled and less skilled readers: Bilingual and bimodal evidence for the linguistic basis of reading

We tested the hypothesis that syntactic and narrative comprehension of a natural sign language can serve as the linguistic basis for skilled reading. Thirty-one adults who were deaf from birth and used American Sign Language (ASL) were classified as skilled or less skilled readers using an eighth-grade criterion. Proficiency with ASL syntax, and narrative comprehension of ASL and Manually Coded English (MCE) were measured in conjunction with variables including exposure to print, nonverbal IQ, and hearing and speech ability. Skilled readers showed high levels of ASL syntatic ability and narrative comprehension whereas less skilled readers did not. Regression analyses showed ASL syntactic ability to contribute unique variance in English reading performance when the effects of nonverbal IQ, exposure to print, and MCE comprehension were controlled. A reciprocal relationship between print exposure and sign language proficiency was further found. The results indicate that the linguistic basis of reading, and the reciprocal relationship between print exposure and "through the air" language, can be bimodal, as in being a sign language, or a spoken language, and bilingual, as in being ASL and English.