Prelexical locus of an illusory vowel effect in Japanese

Studies in vision have demonstrated that the visual system can induce the perception of illusory contours. In this study we document a similar phenomenon in the auditory mode: Japanese speakers report perceiving vowels that are absent in the acoustic signal. Such an illusion is due to the fact that in Japanese, succession of consonants are not allowed. Hence the linguistic system inserts an illusory vowel between adjacent vowels in order to conform to the expected pattern in this language. Here, we manipulate the lexical neighborhood of nonwords that contain illegal consonant clusters and show that this illusion is not due to lexical influence. Rather, it arises before lexical knowledge is activated, suggesting that phonotactics impact perception routines at a very early processing stage.