Vowel normalization as perceptual constancy

This study investigates how listeners associate acoustically different vowels with a single linguistic vowel quality. Listeners were asked to identify vowel sounds as /æ/ or /ʌ/ and to indicate the size of the speaker that produced them. Results indicate that perceived vowel quality trades off with the perception of speaker size: different vowels can sound the same, and the same vowel can sound different when a different speaker is perceived. These findings suggest that vowel normalization is broadly similar to perceptual constancy in other domains, and that social, indexical, and linguistic information play an important role in determining even the most fundamental units of linguistic representation.