Controlling Pitch for Prosody: Sensorimotor Adaptation in Linguistically Meaningful Contexts

This study examined how speakers adapt to fundamental frequency (f_o) errors that affect the use of prosody to convey linguistic meaning, whether f_o 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 f_o and amplitude.

Twenty-four speakers said vowels and sentences while f_o was digitally altered to induce predictable errors. Shifts in f_o (±200 cents) were applied to the entire sustained vowel and one word (emphasized or unemphasized) in sentences. Two prosodic cues-f_o and amplitude-were extracted. The effects of f_o shifts, shift direction, and emphasis on f_o response magnitude were evaluated with repeated-measures analyses of variance. Relationships between adaptive f_o responses in sentences and vowels and between adaptive f_o and amplitude responses were evaluated with Spearman correlations.

Speakers adapted to f_o errors in both linguistically meaningful sentences and linguistically neutral vowels. Adaptive f_o responses of unemphasized words were smaller than those of emphasized words when f_o was shifted upward. There was no relationship between adaptive f_o responses in vowels and emphasized words, but adaptive f_o and amplitude responses were strongly, positively correlated.

Sensorimotor adaptation occurs in response to f_o errors regardless of how disruptive the error is to linguistic meaning. Adaptation to f_o 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 f_o and amplitude supports an integrated model of prosody.

https://doi.org/10.23641/asha.25008908.