Syllable rate drives rate normalization, but is not the only factor
Severijnen, G. G. A., Bosker, H. R., & McQueen, J. M.
Syllable rate drives rate normalization, but is not the only factor. In R. Skarnitzl, & J. Volín (Eds.
), Proceedings of the 20th International Congress of the Phonetic Sciences (ICPhS 2023)
(pp. 56-60). Prague: Guarant International.
Speech is perceived relative to the speech rate in the context. It is unclear, however, what information listeners use to compute speech rate. The present study examines whether listeners use the number of
syllables per unit time (i.e., syllable rate) as a measure of speech rate, as indexed by subsequent vowel perception. We ran two rate-normalization experiments in which participants heard duration-matched word lists that contained either monosyllabic
vs. bisyllabic words (Experiment 1), or monosyllabic vs. trisyllabic pseudowords (Experiment 2). The participants’ task was to categorize an /ɑ-aː/ continuum that followed the word lists. The monosyllabic condition was perceived as slower (i.e., fewer /aː/ responses) than the bisyllabic and
trisyllabic condition. However, no difference was observed between bisyllabic and trisyllabic contexts. Therefore, while syllable rate is used in perceiving speech rate, other factors, such as fast speech processes, mean F0, and intensity, must also influence rate normalization.