Zusammenfassung
In an investigation of contextual influences on sound categorization, 64 Peruvian Spanish listeners categorized vowels on an /i/ to /e/ continuum. First, to measure the influence of the stimulus range (broad acoustic context) and the preceding stimuli (local acoustic context), listeners were presented with different subsets of the Spanish /i/-/e/ continuum in separate blocks. Second, the influence of the number of response categories was measured by presenting half of the participants with /i/ and /e/ as responses, and the other half with /i/, /e/, /a/, /o/, and /u/. The results showed that the perceptual category boundary between /i/ and /e/ shifted depending on the stimulus range and that the formant values of locally preceding items had a contrastive influence. Categorization was less susceptible to broad and local acoustic context effects, however, when listeners were presented with five rather than two response options. Vowel categorization depends not only on the acoustic properties of the target stimulus, but also on its broad and local acoustic context. The influence of such context is in turn affected by the number of internal referents that are available to the listener in a task.
Portions of this work were presented as “The interrelation between the stimulus range and the number of response categories in vowel categorization,” Proceedings of Interspeech 2010, Makuhari, Japan, September 2010, and “The interrelation between the stimulus range and the number of response categories in vowel categorization,” 2nd Pan-American/Iberian Meeting on Acoustics, Cancun, Mexico, November 2010.
J. Acoust. Soc. Am. Volume 131, Issue 4, pp. 3079-3087 (2012); (9 pages)
