Dominant mid-to-high-frequency harmonics predict neural encoding and perception of concurrent vowels with large f0 differences

Authors

Fan-Yin Cheng, Montclair State UniversityFollow
Sarah Medina, University of Texas at Austin
Olaedochim Obinna, University of Texas at Austin
Spencer Smith, University of Texas at AustinFollow

Document Type

Article

Publication Date

8-20-2025

Journal / Book Title

The Journal of the Acoustical Society of America

Abstract

Concurrent vowel perception experiments have revealed the importance of fundamental frequency (f₀) differences in speech stream segregation. Understanding neural processes that support speech streaming using f₀ differences remains an active area of perceptual and neurocomputational modeling research. This study simultaneously measured subcortical neural encoding [frequency following responses (FFRs)] and cued vowel identification accuracy of 12 concurrent vowel mixtures with large f₀ differences (>8 semitones) to assess whether f₀-based neural channel selection predicted perception. Results indicated that the strength of f₀-based neural channel selection for one vowel often depended on the identity of the competing vowel. FFR f₀ amplitudes and cued identification accuracy were predicted by which vowel had more dominant spectral energy in the mid- to high-frequency range (>1500 Hz). Attending to the target vowel in each concurrent vowel mixture did not modulate neural representation of target or nontarget vowels. Together, these findings suggest that speech streaming using f₀ differences may be supported by f₀-based neural channel selection from dominant unresolved harmonics, at least for competing vowels with large f₀ differences.

DOI

10.1121/10.0038969

Rights

© 2025 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). This work is licensed under a Creative Commons Attribution 4.0 International License.

Montclair State University Digital Commons Citation

Cheng, Fan-Yin; Medina, Sarah; Obinna, Olaedochim; and Smith, Spencer, "Dominant mid-to-high-frequency harmonics predict neural encoding and perception of concurrent vowels with large f0 differences" (2025). Department of Communication Sciences and Disorders Faculty Scholarship and Creative Works. 158.
https://digitalcommons.montclair.edu/communcsci-disorders-facpubs/158

Published Citation

Fan-Yin Cheng, Sarah Medina, Olaedochim Obinna, Spencer Smith; Dominant mid-to-high-frequency harmonics predict neural encoding and perception of concurrent vowels with large f0 differences. J. Acoust. Soc. Am. 1 August 2025; 158 (2): 1296–1307. https://doi.org/10.1121/10.0038969