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We examined the neural correlates underlying the semantic processing of native- and nonnative-accented sentences, presented in quiet or embedded in multi-talker noise. Implementing a semantic violation paradigm, 36 English monolingual young adults listened to American-accented (native) and Chinese-accented (nonnative) English sentences with or without semantic anomalies, presented in quiet or embedded in multi-talker noise, while EEG was recorded. After hearing each sentence, participants verbally repeated the sentence, which was coded and scored as an offline comprehension accuracy measure. In line with earlier behavioral studies, the negative impact of background noise on sentence repetition accuracy was higher for nonnative-accented than for native-accented sentences. At the neural level, the N400 effect for semantic anomaly was larger for nativeaccented than for nonnative-accented sentences, and was also larger for sentences presented in quiet than in noise, indicating impaired lexical-semantic access when listening to nonnative-accented speech or sentences embedded in noise. No semantic N400 effect was observed for nonnative-accented sentences presented in noise. Furthermore, the frequency of neural oscillations in the alpha frequency band (an index of online cognitive listening effort) was higher when listening to sentences in noise versus in quiet, but no difference was observed across the accent conditions. Semantic anomalies presented in background noise also elicited higher theta activity, whereas processing nonnative-accented anomalies was associated with decreased theta activity. Taken together, we found that listening to nonnative accents or background noise is associated with processing challenges during online semantic access, leading to decreased comprehension accuracy. However, the underlying cognitive mechanism (e.g., associated listening efforts) might manifest differently across accented speech processing and speech in noise processing.
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Perception of regional and nonnative accents: a comparison of museum laboratory and online data collection
Abstract Online testing for behavioral research has become an increasingly used tool. Although more researchers have been using online data collection methods, few studies have assessed the replicability of findings for speech intelligibility tasks. Here we assess intelligibility in quiet and two noise-added conditions for several different accents of English (Midland American, Standard Southern British, Scottish, German-accented, Mandarin-accented, Japanese-accented, and Hindi-English bilingual). Participants were tested in person at a museum-based laboratory and online. Results showed little to no difference between the two settings for the easier noise condition and in quiet, but large performance differences in the most difficult noise condition with an advantage for the participants tested online. Technology-based variables did not appear to drive the setting effect, but experimenter presence may have influenced response strategy for the in-person group and differences in demographics could have provided advantages for the online group. Additional research should continue to investigate how setting, demographic factors, experimenter presence, and motivational factors interact to determine performance in speech perception experiments.
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- PAR ID:
- 10491800
- Publisher / Repository:
- De Gruyter Mouton
- Date Published:
- Journal Name:
- Linguistics Vanguard
- Volume:
- 9
- Issue:
- s4
- ISSN:
- 2199-174X
- Page Range / eLocation ID:
- 361 to 373
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1515/lingvan-2021-0157
