Evolving theories of vowel perception

Abstract

In the past 15 years, research on the perception of spoken vowels has given rise to new conceptions of vowels as articulatory, acoustic, and perceptual events. This paper traces the evolution of vowel theory starting from “simple” target models in which vowels were characterized articulatorily as static vocal tract shapes and acoustically as points in an F1/F2 vowel space. Within this conceptual framework, two major problems in perception to be accounted for were the Speaker Normalization problem and the Target Undershoot problem. Theoretical developments have taken two directions: (1) “Elaborated” target theories have been hypothesized which account primarily for perceivers' solution of the Speaker Normalization problem; (2) dynamic specification models have been offered (a) to deal with the Target Undershoot problem and (b) to characterize the perceptual significance of vowel diphthongization. Findings of perceptual studies are summarized that motivate these theoretical developments and a characterization is offered of vowels as dynamic gestures giving rise to temporally distributed acoustic information that perceivers utilize in identifying coarticulated vowels. [Research supported by NINCDS.]