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Abstract Recent studies have documented substantial variability among typical listeners in how gradiently they categorize speech sounds, and this variability in categorization gradience may link to how listeners weight different cues in the incoming signal. The present study tested the relationship between categorization gradience and cue weighting across two sets of English contrasts, each varying orthogonally in two acoustic dimensions. Participants performed a four‐alternative forced‐choice identification task in a visual world paradigm while their eye movements were monitored. We found that (a) greater categorization gradience derived from behavioral identification responses corresponds to larger secondary cue weights derived from eye movements; (b) the relationship between categorization gradience and secondary cue weighting is observed across cues and contrasts, suggesting that categorization gradience may be a consistent within‐individual property in speech perception; and (c) listeners who showed greater categorization gradience tend to adopt a buffered processing strategy, especially when cues arrive asynchronously in time. 

Abstract Recent studies have revealed great individual variability in cue weighting, and such variation is shown to be systematic across individuals and linked to differences in some general cognitive mechanism. The present study investigated the role of subcortical encoding as a source of individual variability in cue weighting by focusing on English listeners’ frequency following responses to the tense/lax English vowel contrast varying in spectral and durational cues. Listeners differed in early auditory encoding with some encoding the spectral cue more veridically than the durational one, while others exhibited the reverse pattern. These differences in cue encoding further correlate with behavioral variability in cue weighting, suggesting that specificity in cue encoding across individuals modulates how cues are weighted in downstream processes. 

Phonetic typological studies suggest that syllable duration is inversely correlated with the accompanying tone's approximate average f0, and tones with dynamic f0 movement tend to be in longer syllables rather than shorter ones. Systematic instrumental investigations on tone-duration interaction remain scant, however; existing studies might be confounded as tonal context may impact duration realization due to phonetic constraints on tonal movement. This study investigates the effect of tonal environment on the durational realization of tones in Cantonese, showing that tone-dependent duration variation is governed by the tonal context. Implications of these findings for existing phonetic typology concerning tone-duration interaction are discussed. 

The actuation problem asks why a linguistic change occurs in a particular language at a particular time and space. Responses to this problem are multifaceted. This review approaches the problem of actuation through the lens of sound change, examining it from both individual and population perspectives. Linguistic changes ultimately actuate in the form of idiolectal differences. An understanding of language change actuation at the idiolectal level requires an understanding of ( a) how individual speaker-listeners’ different past linguistic experiences and physical, perceptual, cognitive, and social makeups affect the way they process and analyze the primary learning data and ( b) how these factors lead to divergent representations and grammars across speakers-listeners. Population-level incrementation and propagation of linguistic innovation depend not only on the nature of contact between speakers with unique idiolects but also on individuals who have the wherewithal to take advantage of the linguistic innovations they encountered to achieve particular ideological projects at any given moment. Because of the vast number of contingencies that need to be aligned properly, the incrementation and propagation of linguistic innovation are predicted to be rare. Agent-based modeling promises to provide a controlled way to investigate the stochastic nature of language change propagation, but a comprehensive model of linguistic change actuation at the individual level remains elusive. 

Speech categories are defined by multiple acoustic dimensions and their boundaries are generally fuzzy and ambiguous in part because listeners often give differential weighting to these cue dimensions during phonetic categorization. This study explored how a listener's perception of a speaker's socio-indexical and personality characteristics influences the listener's perceptual cue weighting. In a matched-guise study, three groups of listeners classified a series of gender-neutral /b/-/p/ continua that vary in VOT and F0 at the onset of the following vowel. Listeners were assigned to one of three prompt conditions (i.e., a visually male talker, a visually female talker, or audio-only) and rated the talker in terms of vocal (and facial, in the visual prompt conditions) gender prototypicality, attractiveness, friendliness, confidence, trustworthiness, and gayness. Male listeners and listeners who saw a male face showed less reliance on VOT compared to listeners in the other conditions. Listeners' visual evaluation of the talker also affected their weighting of VOT and onset F0 cues, although the effects of facial impressions differ depending on the gender of the listener. The results demonstrate that individual differences in perceptual cue weighting are modulated by the listener's gender and his/her subjective evaluation of the talker. These findings lend support for exemplar-based models of speech perception and production where socio-indexical features are encoded as a part of the episodic traces in the listeners' mental lexicon. This study also shed light on the relationship between individual variation in cue weighting and community-level sound change by demonstrating that VOT and onset F0 co-variation in North American English has acquired a certain degree of socio-indexical significance. 

Abstract The ability to take contextual information into account is essential for successful speech processing. This study examines individuals with high-functioning autism and those without in terms of how they adjust their perceptual expectation while discriminating speech sounds in different phonological contexts. Listeners were asked to discriminate pairs of sibilant-vowel monosyllables. Typically, discriminability of sibilants increases when the sibilants are embedded in perceptually enhancing contexts (if the appropriate context-specific perceptual adjustment were performed) and decreases in perceptually diminishing contexts. This study found a reduction in the differences in perceptual response across enhancing and diminishing contexts among high-functioning autistic individuals relative to the neurotypical controls. The reduction in perceptual expectation adjustment is consistent with an increase in autonomy in low-level perceptual processing in autism and a reduction in the influence of top-down information from surrounding information.