The effect of subphonetic differences on lexical access.

This study investigated whether lexical access is affected by inherent acoustic variations that contribute to the identity of a phonetic feature and ultimately a phonetic segment. Two experiments were conducted to determine whether the magnitude of semantic (associative) priming in a lexical decision task is influenced when the acoustic manifestation of the initial voiceless stop consonant (specifically, voice onset time) of a prime word semantically related to a lexical decision target was systematically manipulated (e.g., prime: "king"; target: "queen"). Results showed no effect of the acoustic manipulations at the longer interstimulus interval (250 ms); however, at the shorter interstimulus interval (50 ms), the magnitude of semantic facilitation decreased as a function of the voice onset time manipulations. In addition, there was a tendency toward slower lexical decision latencies when the prime word had a real word voiced counterpart than when it did not. These results suggest that activation levels of words in the lexicon are graded, depending on the subphonetic shape of the input word. Results also suggest that words which are phonologically similar to the intended word candidate are activated to some extent, whether the input provides a relatively poor phonetic representation of the intended word or a good one.