The strong, the weak, and the first: The impact of phonological stress on processing of orthographic errors in silent reading.

In auditory speech processing, phonological stress functions as an attention holding cue, which facilitates detection of mispronunciations and phonetic deviants in strong syllables as compared to weak ones. Whereas silent reading involves activation of phonological information including word stress, it is not clear whether it has any functional relevance for visual language processing. We investigated whether phonological stress impacts orthographic processing such as detection of misspellings in silent reading. In an ERP experiment, participants silently read intact and misspelled German words. We manipulated the strength of the misspelled syllable (strong vs. weak) as well as its position (word-initial vs. word-middle). No effect of stress was observed for misspellings occurring in a word-initial position suggesting that misspellings in word-initial position disrupt visual word processing regardless of the phonological strength of the first syllable. In contrast, phonological strength modulated the ERPs when misspellings occurred in the middle of the word: misspellings embedded in strong syllables enhanced the P600 and the N400-like component compared to misspellings in weak syllables. In this case, i.e., when misspellings occur in the middle of a letter string, lexical access may be hindered more when errors occur in strong syllables, as reflected in the enhanced N400 in strong compared to weak syllables. This in turn may facilitate active reanalysis as mirrored in the increased P600 in the strong condition. The findings are discussed in the context of the relatively late activation of phonological form in visual word recognition and its interaction with other perceptual visual information. Overall, the results demonstrate the functional significance of phonological stress in visual word processing.