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Recent work on perceptual learning for speech has suggested that while high-variability training typically results in generalization, low-variability exposure can sometimes be sufficient for cross-talker generalization. We tested predictions of a similarity-based account, according to which, generalization depends on training-test talker similarity rather than on exposure to variability. We compared perceptual adaptation to second-language (L2) speech following single- or multiple-talker training with a round-robin design in which four L2 English talkers from four different first-language (L1) backgrounds served as both training and test talkers. After exposure to 60 L2 English sentences in one training session, cross-talker/cross-accent generalization was possible (but not guaranteed) following either multiple- or single-talker training with variation across training-test talker pairings. Contrary to predictions of the similarity-based account, adaptation was not consistently better for identical than for mismatched training-test talker pairings, and generalization patterns were asymmetrical across training-test talker pairs. Acoustic analyses also revealed a dissociation between phonetic similarity and cross-talker/cross-accent generalization. Notably, variation in adaptation and generalization related to variation in training phase intelligibility. Together with prior evidence, these data suggest that perceptual learning for speech may benefit from some combination of exposure to talker variability, training-test similarity, and high training phase intelligibility.
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Perceptual learning alters effects of foreign language backgrounds in speech-in-speech recognition
The effect of training on linguistic release from masking (LRM) was examined. In a pre-test and post-test, English monolingual listeners transcribed sentences presented with English and Dutch maskers. During training, participants transcribed sentences with either Dutch, English, or white noise maskers and received feedback. LRM was evident in the pre-test (performance was better with Dutch maskers) but was eliminated after training (masker conditions did not differ). Thus, the informational masking driving LRM can be ameliorated through training. This study is a basis for future research examining the specific aspects of informational masking that change as a function of experience.
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- Award ID(s):
- 2126888
- PAR ID:
- 10589344
- Publisher / Repository:
- Acoustical Society of America (ASA)
- Date Published:
- Journal Name:
- JASA Express Letters
- Volume:
- 2
- Issue:
- 8
- ISSN:
- 2691-1191
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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