The First Words Acquired by Adolescent First - Language Learners : When Late Looks Early

What does language acquisition look like when it begins for the first time in adolescence? This question is difficult to answer because virtually all hearing children are exposed to spoken language from birth. Unlike the acquisition of spoken languages, however, the acquisition of signed languages is frequently delayed. In the USA, about 90% of deaf children are born to hearing parents who do not know any sign language (Schein, 1989). Because most deaf infants do not have access to early linguistic input, they are at risk for language delay. In rare cases, deaf individuals are cut-off from all linguistic input until adolescence due to anomalies in their upbringing combined with a number of societal and educational factors. The question that the current study explores is how these extremely late learners begin their linguistic journey once they are immersed in a language that is fully accessible to them, in this case American Sign Language (ASL). Can they use their cognitive maturity and previous nonlinguistic communicative experience to leapfrog the initial stages of language acquisition? Or must they move through the well-documented set of early linguistic milestones in a manner analogous to children? Sign languages are natural languages that are expressed with the hands and face and understood through the eyes. Decades of research have demonstrated that sign languages are linguistically equivalent to spoken languages and are structured at the level of syntax, semantics, morphology, and phonology (Klima and Bellugi, 1979; Stokoe, Casterline, and Cronneberg, 1965). Cross-linguistic studies demonstrate that, when begun at birth, the acquisition patterns for sign languages generally parallel those for spoken languages (Anderson and Reilly, 2002; Mayberry and Squires, 2006). Deaf infants born to deaf parents produce manual babbling at 6 to 12 months, which corresponds to the age of onset of