Grapheme-to-lexeme feedback in the spelling system: Evidence from a dysgraphic patient.

This article presents an argument for grapheme-to-lexeme feedback in the cognitive spelling system, based on the impaired spelling performance of dysgraphic patient CM. The argument relates two features of CM's spelling. First, letters from prior spelling responses intrude into subsequent responses at rates far greater than expected by chance. This letter persistence effect arises at a level of abstract grapheme representations, and apparently results from abnormal persistence of activation. Second, CM makes many formal lexical errors (e.g., carpet → compute). Analyses revealed that a large proportion of these errors are "true" lexical errors originating in lexical selection, rather than "chance" lexical errors that happen by chance to take the form of words. Additional analyses demonstrated that CM's true lexical errors exhibit the letter persistence effect. We argue that this finding can be understood only within a functional architecture in which activation from the grapheme level feeds back to the lexeme level, thereby influencing lexical selection.