Effects of lexical stress on phonetic categorization

Three experiments investigated the use of lexical stress in auditory word recognition. Speech voicing continua were created in which lexical status resulted in one end-point constituting a real word and the other end a nonword (e.g. diGRESS-tiGRESS, in which digress is a real word, and DIgress-Tigress, in which tigress is a real word). Subjects' identification of the initial segment of these items was biased in the midrange of the continua in that they were more likely to report a segment that resulted in a real word than one that resulted in a nonword. Alternative acoustically based explanations are discounted in favor of a lexically based account of the data. Possible mechanisms underlying the effect of lexical stress on speech perception are discussed.