Sensorimotor adaptation of pitch for prosody (Dahl et al., 2024)
Purpose: This study examined how speakers adapt to fundamental frequency (fo) errors that affect the use of prosody to convey linguistic meaning, whether fo adaptation in that context relates to adaptation in linguistically neutral sustained vowels, and whether cue trading is reflected in responses in the prosodic cues of fo and amplitude.
Method: Twenty-four speakers said vowels and sentences while fo was digitally altered to induce predictable errors. Shifts in fo (±200 cents) were applied to the entire sustained vowel and one word (emphasized or unemphasized) in sentences. Two prosodic cues— fo and amplitude—were extracted. The effects of fo shifts, shift direction, and emphasis on fo response magnitude were evaluated with repeated-measures analyses of variance. Relationships between adaptive fo responses in sentences and vowels and between adaptive fo and amplitude responses were evaluated with Spearman correlations.
Results: Speakers adapted to fo errors in both linguistically meaningful sentences and linguistically neutral vowels. Adaptive fo responses of unemphasized words were smaller than those of emphasized words when fo was shifted upward. There was no relationship between adaptive fo responses in vowels and emphasized words, but adaptive fo and amplitude responses were strongly, positively correlated.
Conclusions: Sensorimotor adaptation occurs in response to fo errors regardless of how disruptive the error is to linguistic meaning. Adaptation to fo errors during sustained vowels may not involve the exact same mechanisms as sensorimotor adaptation as it occurs in meaningful speech. The relationship between adaptive responses in fo and amplitude supports an integrated model of prosody.
Supplemental Material S1. Group mean adaptive response in amplitude to downward (Panel A) and upward (Panel B) shifts in auditory feedback of fo (±200 cents) during emphasized (blue) and unemphasized (dashed pink) words in running speech. Shaded areas are 95% confidence intervals.
Supplemental Material S2. Group mean adaptive response in amplitude to a 200-cent downward shift in auditory feedback of fo during sustained vowels. Shaded area is 95% confidence interval.
Supplemental Material S3. Results of repeated-measures analyses of variance for normalized fundamental frequency (fo) during sustained vowels and sentences with emphasized and unemphasized words, based on data extracted from the entire vowel/word (full window).
Dahl, K. L., Cádiz, M. D., Zuk, J., Guenther, F. H., & Stepp, C. E. (2024). Controlling pitch for prosody: Sensorimotor adaptation in linguistically meaningful contexts. Journal of Speech, Language, and Hearing Research, 67(2), 440–454. https://doi.org/10.1044/2023_JSLHR-23-00460