Orthographic Influences on Sublexical Processing

Adults with language impairment have poor language skills, but may or may not have reading deficits. For those identified with literacy difficulties as children, deficits in the skills related to sublexical level decoding skills can persist into adulthood. Decoding deficits, current or remediated, would implicate the sublexical interaction of orthography and phonology. In addition, the heterogeneous reading profiles of adults with language impairment provide an opportunity to examine whether the deficits in this bidirectional link between orthography and phonology are related to reading deficit specifically or language impairment globally. Sixty adults, 30 with language impairment and 30 with typical language, participated in this study. Nonword stimuli, orthogonally varied based on orthographic and phonological neighborhood density, were presented in two sublexical tasks, nonword repetition and nonword spelling. The experiment revealed a pattern of similar responses for adults with and without language impairment. However, adults with impaired language had significantly poorer performance on both the nonword repetition task and the nonword spelling task. Additional analyses indicated that both language and literacy measures predicted the overall performance on the orthogonally varied nonword repetition and nonword spelling tasks. This study highlights the existence of a bidirectional influence between phonological and orthographic processing. For adults with language impairment it appears that this bidirectional link is intact at the sublexical level