What the reader's eye tells the mind's ear: silent reading activates inner speech

Although copious research has investigated the role of phonology in reading, little research has investigated the precise nature of the entailed speech representations. The present study examined the similarity of "inner speech" in reading to overt speech. Two lexical decision experiments (in which participants gave speeded word/nonword classifications to letter strings) assessed the effects of implicit variations in vowel and word-initial consonant length. Responses were generally slower for phonetically long stimuli than for phonetically short stimuli, despite equal orthographic lengths. Moreover, the phonetic length effects displayed principled interactions with common factors known to affect lexical decisions, such as word frequency and the similarity of words to nonwords. Both phonetic length effects were stronger among slower readers. The data suggest that acoustic representations activated in silent reading are best characterized as inner speech rather than as abstract phonological codes.