Influence of Talker and Accent Variability on Rapid Adaptation and Generalization to Non-Native Accented Speech in Younger and Older Adults

ABSTRACT

Listeners can rapidly adapt to English speech produced by non-native speakers of English with unfamiliar accents. Prior work has shown that the type and number of talkers contained within a stimulus set may impact rate and magnitude of learning, as well as any generalization of learning. However, findings across the literature have been inconsistent, with relatively little study of these effects in populations of older listeners. In this study, adaptation and generalization to unfamiliar talkers with familiar and unfamiliar accents are studied in younger normal-hearing adults and older adults with and without hearing loss. Rate and magnitude of adaptation are modeled using both generalized linear mixed-effects regression and generalized additive mixed-effects modeling. Rate and magnitude of adaptation were not impacted by increasing the number of talkers and/or varying the consistency of non-native English accents across talkers. Increasing the number of talkers did strengthen generalization of learning for a talker with a familiar non-native accent, but not for an unfamiliar accent. Aging alone did not diminish adaptation or generalization. These findings support prior evidence of a limited benefit for talker variability in facilitating generalization of learning for non-native accented speech, and extend the findings to older adults.

KEYWORDS:

• Non-native speech
• aging
• hearing
• adaptation
• learning
• generalization

Acknowledgments

The authors would like to thank Sarah Elazar for her assistance with data collection.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported in part by training grant T32DC00046 from the National Institute of Deafness and Communicative Disorders of the National Institutes of Health (RB trainee; SGS Co-PI), the Dean’s Graduate Student Advisory Council (Bieber) and the MCM Fund for Student Research Excellence (Bieber). The work was conducted in a laboratory funded by the National Institute on Aging of the NIH [R01AG009191 and R37AG009191] (awarded to SGS).