Sublexical Conversion Procedures and the Interaction of Phonological and Orthographic Lexical Forms

In double naming tasks requiring the production of consecutive spoken and written responses to the same picture, subject ECA produced inconsistent lexical responses in the say-then-write (stimulus: organ; spoken response: “church;” written response: piano) but not in the write-then-say condition (organ ® piano ® “piano”). This observation, together with the fact that ECA had damage to the semantic system and to sublexical phoneme-grapheme conversion but not to sublexical grapheme-phoneme conversion procedures, is used to constrain claims about the organisation of lexical form knowledge. It is proposed that phonological and orthographic lexical forms are accessed autonomously, but interact via sublexical conversion procedures. In ECA, the one-way interaction between phonological and orthographic word forms is prevented by damage to phonemegrapheme procedures (hence, inconsistent responses in the say-then-write naming condition); the reverse interaction can take place because grapheme-phoneme conversion processes are spared (hence, the absence of inconsistent responses in the write-then-say naming condition).