An alternative to grapheme-phoneme conversion rules?

When orthographic factors were tightly controlled in a lexical decision task, it was observed that orthographic similarity rather than homophony with a word led to increased reaction times to nonwords. This result suggested that the pseudohomophone effect is not a phonological effect. Instead, a conversion of the graphemes of a stimulus item into different graphemes via a set of grapheme-grapheme conversion rules was supported. When phonological factors were tightly controlled and orthographic similarity varied, evidence for the existence of grapheme-grapheme rules was provided in both a lexical decision task and a task in which subjects were required to say whether an item was pronounced in the same way as a word. Even in the latter task, in which the likelihood of phonological recoding was optimized, it appeared that grapheme-phoneme rules were rarely, if ever, used.