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Purpose The “bubble noise” technique has recently been introduced as a method to identify the regions in time–frequency maps (i.e., spectrograms) of speech that are especially important for listeners in speech recognition. This technique identifies regions of “importance” that are specific to the speech stimulus and the listener, thus permitting these regions to be compared across different listener groups. For example, in cross-linguistic and second-language (L2) speech perception, this method identifies differences in regions of importance in accomplishing decisions of phoneme category membership. This research note describes the application of bubble noise to the study of language learning for 3 different language pairs: Hindi English bilinguals' perception of the /v/–/w/ contrast in American English, native English speakers' perception of the tense/lax contrast for Korean fricatives and affricates, and native English speakers' perception of Mandarin lexical tone. Conclusion We demonstrate that this technique provides insight on what information in the speech signal is important for native/first-language listeners compared to nonnative/L2 listeners. Furthermore, the method can be used to examine whether L2 speech perception training is effective in bringing the listener's attention to the important cues.
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This content will become publicly available on January 10, 2026
Incidental Nonspeech Auditory Learning Scaffolds Phonetic, Category, and Word Learning in a Foreign Language Classroom
Abstract There is considerable lab‐based evidence for successful incidental learning, in which a learner's attention is directed away from the to‐be‐learned stimulus and towards another stimulus. In this study, we extend incidental learning research into the language learning classroom. Three groups of adult second language (L2) learners (N= 52) engaged in structured classroom Mandarin learning took part in an 8‐week study. One group served as a classroom‐only control group. The second group underwent additional intentional auditory training involving Mandarin speech and explicit feedback. The third group underwent additional incidental learning combined with nonspeech “perceptual building block” categories—categories that share critical perceptual dimensions with target L2 speech categories but that are not perceived as speech. We demonstrate that when supplemented with structured classroom learning, incidental learning involving nonspeech analogs promotes phonetic, category, and word learning equivalent to learning from more traditional intentional auditory training.
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- Award ID(s):
- 2420979
- PAR ID:
- 10611903
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Language Learning
- ISSN:
- 0023-8333
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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