There is ample evidence that motor learning changes the function of perceptual systems. Previous studies examining the interactions between speech production and perception have shown that the discrimination of phonetic contrasts characterized by the difference in articulatory place features is altered following their production changes caused by the perturbation of auditory feedback. The present study focused on a voiced-voiceless contrast in stop consonants, which is characterized by a temporal articulatory parameter, voice-onset time (VOT). In the experiment, we manipulated the participants' motor functions concerning VOT using a cross-categorical auditory feedback (CAF) paradigm (Mitsuya et al. in J Acoust Soc Am 135:2986-2994, 2014), in which a pre-recorded syllable sound starting with a voiced stop consonant (/da/) was fed back simultaneously with the participant's utterance of a voiceless stop consonant (/ta/), and vice versa. The VOT difference between /da/ and /ta/ productions was increased by the CAF, which is consistent with the result of Mitsuya's study. In addition, we conducted perceptual identification tasks of /da/-/ta/ continuum stimuli varying in VOT before and after the CAF task, and found that the identification function became sharper after as compared to before the CAF task. A significant positive correlation between such production and perception changes was also found. On the basis of these results, we consider that the change in motor function concerning VOT affected voiced-voiceless perceptual processing. The present study is the first to show the involvement of the speech production system in the perception of phonetic contrasts characterized by articulatory temporal features.
Keywords: Cross-categorical auditory feedback; Voice-onset time; Voicing perception; Voicing production.