Native talkers are able to enhance acoustic characteristics of their speech in a speaking style known as “clear speech,” which is better understood by listeners than “plain speech.” However, despite substantial research in the area of clear speech, it is less clear whether non-native talkers of various proficiency levels are able to adopt a clear speaking style and if so, whether this style has perceptual benefits for native listeners. In the present study, native English listeners evaluated plain and clear speech produced by three groups: native English talkers, non-native talkers with lower proficiency, and non-native talkers with higher proficiency. Listeners completed a transcription task (i.e., an objective measure of the speech intelligibility). We investigated intelligibility as a function of language background and proficiency and also investigated the acoustic modifications that are associated with these perceptual benefits. The results of the study suggest that both native and non-native talkers modulate their speech when asked to adopt a clear speaking style, but that the size of the acoustic modifications, as well as consequences of this speaking style for perception differ as a function of language background and language proficiency.
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The Effects of Acoustic and Semantic Enhancements on Perception of Native and Non-Native Speech
Previous research has shown that native listeners benefit from clearly produced speech, as well as from predictable semantic context when these enhancements are delivered in native speech. However, it is unclear whether native listeners benefit from acoustic and semantic enhancements differently when listening to other varieties of speech, including non-native speech. The current study examines to what extent native English listeners benefit from acoustic and semantic cues present in native and non-native English speech. Native English listeners transcribed sentence final words that were of different levels of semantic predictability, produced in plain- or clear-speaking styles by Native English talkers and by native Mandarin talkers of higher- and lower-proficiency in English. The perception results demonstrated that listeners benefited from semantic cues in higher- and lower-proficiency talkers’ speech (i.e., transcribed speech more accurately), but not from acoustic cues, even though higher-proficiency talkers did make substantial acoustic enhancements from plain to clear speech. The current results suggest that native listeners benefit more robustly from semantic cues than from acoustic cues when those cues are embedded in non-native speech.
more » « less- NSF-PAR ID:
- 10403439
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Language and Speech
- Volume:
- 67
- Issue:
- 1
- ISSN:
- 0023-8309
- Format(s):
- Medium: X Size: p. 40-71
- Size(s):
- p. 40-71
- Sponsoring Org:
- National Science Foundation
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Significance Statement Behavioral experiments suggest that native language knowledge interferes with foreign language listening, but such effects may be sensitive to task manipulations, as tasks that increase metalinguistic awareness may also increase native language interference. This highlights the need for studying non-native speech processing using naturalistic tasks. We measured neural responses unobtrusively while participants listened for comprehension and characterized the influence of proficiency at multiple levels of representation. We found that salience of the native language, as manipulated through speaker accent, affected activation of native language representations: significant evidence for activation of native language (Dutch) categories was only obtained when the speaker had a Dutch accent, whereas no significant interference was found to a speaker with a native (American) accent. -
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Abstract For nearly 25 years, researchers have recognized the rich and numerous facets of native perception of non‐native speech, driving a large, and growing, body of work that has shed light on how native listeners understand non‐native speech. The bulk of this work, however, has focused on the talker. That is, most researchers have asked what perception of non‐native speech tells us about the non‐native speaker, or when interacting with non‐native speakers more generally. It is clear that listeners perceive speech not only in terms of the acoustic signal, but also with their own experience and biases driving their perception. It is also clear that native listeners can improve their perception of non‐native speech for both familiar and unfamiliar accents. Therefore, it is imperative that research in non‐native communication also consider an active role for the listener. To truly understand communication between native and non‐native speakers, it is critically important to understand both the properties of non‐native speech and how this speech is perceived. In the present review, we describe non‐native speech and then review previous research, examining the methodological shift from using native listeners as tools to understand properties of non‐native speech to understanding listeners as partners in conversation. We discuss how current models not only limit our understanding of non‐native speech, but also limit what types of questions researchers set out to answer. We demonstrate that while non‐native speakers capable of shifting their productions to be better understood by listeners, native listeners are also capable of shifting their perception to more accurately perceive non‐native speech. We conclude by setting forth a series of recommendations for future research, emphasizing the contributions of native listeners and non‐native speakers as equally important for communicative success.
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