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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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Exploring effects of brief daily exposure to unfamiliar accent on listening performance and cognitive load
IntroductionListeners rapidly “tune” to unfamiliar accented speech, and some evidence also suggests that they may improve over multiple days of exposure. The present study aimed to measure accommodation of unfamiliar second language- (L2-) accented speech over a consecutive 5-day period using both a measure of listening performance (speech recognition accuracy) and a measure of cognitive load (a dual-task paradigm). MethodsAll subjects completed a dual-task paradigm with L1 and L2 accent on Days 1 and 5, and were given brief exposure to either L1 (control group) or unfamiliar L2 (training groups) accent on Days 2–4. One training group was exposed to the L2 accent via a standard speech transcription task while the other was exposed to the L2 accent via a transcription task that included implicit feedback (i.e., showing the correct answer after each trial). ResultsAlthough overall improvement in listening performance and reduction in cognitive load were observed from Days 1 to 5, our results indicated neither a larger benefit for the L2 accent training groups compared to the control group nor a difference based on the implicit feedback manipulation. DiscussionWe conclude that the L2 accent trainings implemented in the present study did not successfully promote long-term learning benefits of a statistically meaningful magnitude, presenting our findings as a methodologically informative starting point for future research on this topic.
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- PAR ID:
- 10530863
- Publisher / Repository:
- Frontiers in Language Sciences
- Date Published:
- Journal Name:
- Frontiers in Language Sciences
- Volume:
- 3
- ISSN:
- 2813-4605
- 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/10.3389/flang.2024.1243678
