Asymmetries in Perceptual Adjustments to Non-Canonical Pronunciations

Abstract

Listeners need to accommodate pronunciations that vary widely. Lexically-guided perceptual adaptation has been well documented in the literature, but relatively little is known about its limits. Moreover, there are at least two plausible mechanisms supporting adaptation for sound categories: targeted shifts towards the novel pronunciation or a general relaxation of criteria. This paper examines a limit of perceptual adaptation — asymmetries in adaptation to the voicing and devoicing of coronal fricatives in English — and suggests that typology or synchronic experience affects how listeners adapt. A corpus study of coronal fricative substitution patterns confirmed that North American English listeners are more likely to be exposed to devoiced /z/ than voiced /s/. Across two perceptual adaptation experiments, listeners in test conditions head naturally produced devoiced /z/ or voiced /s/ in critical items within sentences, while control listeners were exposed to identical sentences with canonical fricative pronunciations. Perceptual adaptation was tested via word endorsement rates in a lexical decision test, with devoiced /z/ or voiced /s/, as well as a novel alveopalatalized pronunciation, to determine whether adaptation was targeted in the direction of the exposed variant or reflected more general relaxation. Results indicate there was targeted and word-specific adaptation for /z/ devoicing. Conversely, there was some evidence of /s/ voicing eliciting a more general category relaxation. These results underscore the role of prior perceptual experiences, and suggest a need for an evaluation stage in lexically-guided perceptual learning, where listeners assess whether a heard item merits an update to the representation.

Social priming: Exploring the effects of speaker race and ethnicity on perception of second language accents

“…Our examination of specificity effects also had the potential to inform our understanding of the mechanisms that support perceptual accommodation of L2 accent. We suggested that a phonemic recalibration mechanism may support targeted adjustments to L2 accent (see discussion by Melguy & Johnson, 2021) while a criteria relaxation mechanism (Zheng & Samuel, 2020;Babel et al, 2021) may support more generalized preparation for (non-specific) L2 accent. Although the present results are inconclusive, there is evidence that could support either account.…”

“…However, as reviewed above, there are mixed outcomes across the literature for social priming effects (McGowan, 2015;Babel & Russell, 2015;Hanulíková, 2021;Melguy & Johnson, 2021;Kutlu et al, 2022). Further, the role of a phonemic recalibration mechanism in accent accommodation is uncertain (Xie et al, 2018;Zheng & Samuel, 2020), and some evidence indicates that accommodation may (at least in some circumstances) be supported by a criteria relaxation mechanism (Babel et al, 2021). In the present study, we aimed to explore these inter-related issues using a social priming experiment.…”