Clues to the cognitive organization of reading and writing from developmental hyperlexia.

Controversies regarding the organization of the cognitive systems used for processing written language were investigated in a case study of a mentally retarded hyperlexic child. Despite severe impairments in semantic processing, this child demonstrated intact phonological and orthographic processing. Detailed assessments of his nonword reading abilities provided support for the hypothesis that phonological processing of written words was accomplished by using lexical representations instead of applying nonlexical grapheme-phoneme transcoding rules. Longitudinal investigation of the hyperlexic child's development of writing supports the notion that reading and spelling rely on common mental representations rather than separate input and output mental lexicons. (PsycINFO Database Record (c) 2010 APA, all rights reserved)