Date of Degree


Document Type


Degree Name





Kyle Gorman

Committee Members

Gita Martohardjono

Subject Categories

First and Second Language Acquisition | Phonetics and Phonology | Psycholinguistics and Neurolinguistics


perceptual magnet effect, contact-induced sound change, bilingualism, speech perception, prototype theory


Previous research has demonstrated an apparent warping of the perceptual space whereby the best exemplars or ‘prototypes’ of speech sound categories minimize the perceptual distance between themselves and neighboring stimuli in the same category. This phenomenon has been termed the ‘perceptual magnet effect’ (PME). The present study extends work on the PME to a speech sound category previously unstudied in this paradigm (American English /æ/), and to bilingual speech sound representation and perception. American English monolinguals and Turkish-English bilinguals completed identification tasks, category goodness rating tasks, and same-different discrimination tasks with synthesized vowel sounds from the American English /æ/ category—not present in Turkish—and the Turkish /y/ category—not present in English. Results from the identification and goodness rating tasks provided evidence for internal gradedness within these vowel categories. However, results from the discrimination tasks did not provide clear evidence for the PME in either participant group for either set of vowel stimuli. These results, in combination with previous non-replications of the PME, suggest that the PME is not a robust, language-specific effect. However, the cognitive representations of speech sound categories likely have some effects on bilingual speech perception, and these categorical effects may play a role in contact-induced sound change.