A comparison of phonetic convergence in conversational interaction and speech shadowing

Phonetic convergence is a form of variation in speech production in which a talker adopts aspects of another talker's acoustic-phonetic repertoire. To date, this phenomenon has been investigated in non-interactive laboratory tasks extensively and in conversational interaction to a lesser degree. The present study directly compares phonetic convergence in conversational interaction and in a non-interactive speech shadowing task among a large set of talkers who completed both tasks, using a holistic AXB perceptual similarity measure. Phonetic convergence occurred in a new role-neutral conversational task, exhibiting a subtle effect with high variability across talkers that is typical of findings reported in previous research. Conversational phonetic convergence did not differ by talker sex on average, but relationships between speech shadowing and conversational convergence differed according to talker sex, with female talkers showing no consistency across settings in their relative levels of convergence and male talkers showing a modest relationship. These findings indicate that phonetic convergence is not directly compatible across different settings, and that phonetic convergence of female talkers in particular is sensitive to differences across different settings. Overall, patterns of acoustic-phonetic variation and convergence observed both within and between different settings of language use are inconsistent with accounts of automatic perception-production integration.