Acoustic and articulatory measures of prosodic convergence in a cooperative maze navigation task
Yoonjeong Lee, Samantha Gordon Danner, Benjamin Parrell, Sungbok Lee, Louis Goldstein, Dani Byrd · The Journal of the Acoustical Society of America · 2016
Convergence effects have been found in many aspects of communication between speakers in conversation. This study examines how phonetic properties of each speaker’s prosodic structure differ before, during and after participating in a cooperative maze task. Using two NDI electromagnetic articulatory tracking systems simultaneously, we recorded speakers of American English in dyads (one male dyad & one female dyad). Acoustic measurements included: 1) sentence durations, 2) phrase-final lengthening, 3) occurrence frequency of sentence-final boundary tones (percentage H%), and 4) peak F0 values in sentence-final words. Articulatory boundary strength measures for word-final consonant(s) articulations included: 1) movement durations, 2) displacement, and 3) time-to-peak velocity in phrase-medial and phrase-final positions. Speakers exhibited distinct phonetic patterns before the cooperative maze task. However, conversing speakers showed convergence effects in prosodic boundary strength, choice of boundary tone, and quantitative characteristics of boundary tone. Convergence effects persisted in the speech of one or both members of each dyad even after conversation has ended. Our findings raise the possibility that qualitative and quantitative aspects of prosody can be modeled as arising from a single system of control and that this system of prosodic structuring can show coupling effects across speakers. [Work supported by NIH.]