Effects of listeners' dialectal variation on comprehensibility and accentedness judgements of second language speech

This study investigated the impact of listeners' dialectal variations within the same L1 on perceptions of L2 speech comprehensibility and accentedness. Thirty untrained British and American English-L1 raters assessed recorded L2 speech samples from 29 Finnish learners of English and provided scalar judgments for their comprehensibility and accentedness. Four linguistically trained graduate students evaluated the samples for segmental accuracy, speech rate, word stress and intonation. Results of linear mixed models indicated no significant effect of raters' L1 variety on global comprehensibility and accentedness ratings. While American and British raters relied on same pronunciation features in their comprehensibility judgments, they placed different levels of importance on pronunciation features when making accentedness judgments. Particularly, both groups primarily exhibited sensitivity towards segmental errors in their assessments of accentedness, whereas American raters demonstrated an additional sensitivity to intonation. The findings underscore the complexity of accent perception based on the L1 variety of listeners.