Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Date of Graduation

Spring 2014

Document Type


Degree Name

Master of Arts (MA)


Department of Graduate Psychology


Previous research investigating the parameters that affect accent have concentrated mainly on talker characteristics (e.g Flege, 1988). Those studies that do attempt to investigate acoustic parameters rely on post-hoc analysis of signals already judged to be accented. Any acoustic differences between these signals are said to be the basis of accent judgments. The current investigation attempts to rectify this methodological flaw by manipulating acoustic parameter previously implicated in perceived foreign accent within synthesized speech. In a two experiment study we investigate the effect of consonant duration and consonant initial frequency (Experiment 1) along with voice onset time, vowel duration and stop closure duration (Experiment 2). All stimuli were presented to participants over headphones using E-prime 2.0 experimental software. Participants were asked to perform two tasks: an initial phoneme identification task and an accent rating task. Identification accuracy was not expected to change based on our manipulation. Accent ratings were expected to increase as parameters approached non-native values. Consonant duration and initial frequency failed to have any effect on accent due to flaws in our synthesis. This could be a by-product of synthesis issues apparent by unexpected detrimental effects of our manipulation on identification accuracy. VOT and vowel duration significantly impacted accent ratings while stop closure duration did not. These finding suggest that listeners do rely on temporal parameters of speech in their judgment of accent. Suggestions for methodological standards are given.

Included in

Psychology Commons



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