Perception of foreign accent in Spanish by native and nonnative listeners: Investigating the role of VOT and speech rate

Previous research on the perception of foreign accent has focused on the ratings of native and near-native listeners and few studies have explored the perception of degree of foreign accent by nonnative listeners, despite the fact that it could shed light on what language learners perceive as foreign-accented and potentially tell us about their developing system. The present dissertation aims to investigate the perception of degree of foreign accent in Spanish by both native and nonnative listeners, exploring the effects of various listener-specific characteristics, including proficiency, on listeners' perception. This thesis also explores the role of VOT and speech rate in nonnative listeners' perception of foreign accent in Spanish, two cues that have been found to influence native listeners' perception of foreign-accented English in previous studies.
In order to accomplish these goals the read speech of 2 native and 2 nonnative Spanish speakers, in addition to 11 distracter speakers, was recorded and Praat's duration tool was used to create VOT and rate-modified versions of the read sentences. A total of 26 native speakers and 140 nonnative learners of Spanish heard and rated 210 modified and unmodified utterances on a 9-point scale of degree of foreign accent. The statistical analyses revealed significant differences between native and nonnative listeners' ratings of unmodified speech. In the analyses that compared listener ratings of modified and unmodified utterances, both sets of listeners rated speech as more accented when it had longer (less native-like) VOTs and when it was slower. Conversely, listeners also rated nonnative speech as less foreign-accented when it was reproduced with shorter VOTs and at a faster rate. A number of listener-specific factors including proficiency, course enrollment, pronunciation training, comprehension, and native dialect exposure were also found to be significant predictors of listeners' foreign accent perception. The results show that both linguistic and listener characteristics affect the perception of foreign accent by native and nonnative listeners of Spanish, and that contrary to previous findings these two listener groups do not necessarily perceive degree of foreign accent the same.