Identification of vowels in "vowelless" syllables.

Abstract

Traditionally, it has been held that the primary information for vowel identification is provided by formant frequencies in the quasi-steady-state portion of the spoken syllable. Recent search has advanced an alternative view that emphasizes the role of temporal factors and dynamic (time-varying) spectral information in determining the perception of vowels. Nine vowels spoken in /b/ + vowel + /b/ syllables were recorded. The syllables were modified electronically in several ways to suppress various sources of spectral and durational information. Two vowel-perception experiments were performed, testing subjects’ ability to identify vowels in these modified syllables. Results of both experiments revealed the importance of dynamic spectral information at syllable onset and offset (in its proper temporal relation) in permitting vowel identification. On the other hand, steady-state spectral information, deprived of its durational variation, was a poor basis for identification. Results constitute a challenge to traditional accounts of vowel perception and point toward important sources of dynamic information.