The production of /s/-stop clusters by pre-schoolers with hearing loss.

Producing word-initial /s/-stop clusters can be a challenge for English-speaking pre-schoolers. For children with hearing loss (HL), fricatives can be also difficult to perceive, raising questions about their production and representation of /s/-stop clusters. The goal of this study was therefore to determine if pre-schoolers with HL can produce and represent the /s/ in word-initial /s/-stop clusters, and to compare this to their normal hearing (NH) peers. Based on both acoustic and perceptual analysis, we found that children with HL had little /s/-omission, suggesting that their phonological representation of these clusters closely aligns with that of their NH peers.

The Acquisition of Acoustic Cues to Onset and Coda Voicing Contrasts by Preschoolers With Hearing Loss.

PURPOSE: Children with hearing loss (HL), including those with hearing aids (HAs) and cochlear implants (CIs), often have difficulties contrasting words like " b each" versus " p each" and "do g " versus "do ck " due to challenges producing systematic voicing contrasts. Even when acoustic contrasts are present, these may not be perceived as such by others. This can cause miscommunication, leading to poor self-esteem and social isolation. Acoustic evidence is therefore needed to determine if these children have established distinct voicing categories before entering school and if misperceptions are due to a lack of phonological representations or due to a still-maturing implementation system. The findings should help inform more effective early intervention. METHOD: Participants included 14 children with HL (eight HA users, five CI users, and one bimodal) and 20 with normal hearing, all English-speaking preschoolers. In an elicited imitation task, they produced consonant-vowel-consonant minimal pair words that contrasted voicing in word-initial (onset) or word-final (coda) position at all three places of articulation (PoAs). RESULTS: Overall, children with HL showed acoustically distinct voicing categories for both onsets and codas at all three PoAs. Contrasts were less systematic for codas than for onsets, as also confirmed by adults' perceptual ratings. CONCLUSIONS: Preschoolers with HL produce acoustic differences for voiced versus voiceless onsets and codas, indicating distinct phonological representations for both. Nonetheless, codas were less accurately perceived by adult raters, especially when produced by CI users. This suggests a protracted development of the phonetic implementation of codas, where CI users, in particular, may benefit from targeted intervention.

Children with hearing loss can predict during sentence processing.

Listeners readily anticipate upcoming sentence constituents, however little is known about prediction when the input is suboptimal, such as for children with hearing loss (HL). Here we examined whether children with hearing aids and/or cochlear implants use semantic context to predict upcoming spoken sentence completions. We expected reduced prediction among children with HL, but found they were able to predict similarly to children with normal hearing. This suggests prediction is robust even when input quality is chronically suboptimal, and is compatible with the idea that recent advances in the management of pre-lingual HL may have minimised some of the language processing differences between children with and without HL.

Acoustic cues to coda stop voicing contrasts in Australian English-speaking children.

While voicing contrasts in word-onset position are acquired relatively early, much less is known about how and when they are acquired in word-coda position, where accurate production of these contrasts is also critical for distinguishing words (e.g., dog vs. dock). This study examined how the acoustic cues to coda voicing contrasts are realized in the speech of 4-year-old Australian English-speaking children. The results showed that children used similar acoustic cues to those of adults, including longer vowel duration and more frequent voice bar for voiced stops, and longer closure and burst durations for voiceless stops along with more frequent irregular pitch periods. This suggests that 4-year-olds have acquired productive use of the acoustic cues to coda voicing contrasts, though implementations are not yet fully adult-like. The findings have implications for understanding the development of phonological contrasts in populations for whom these may be challenging, such as children with hearing loss.

Temporal cues to onset voicing contrasts in Australian English-speaking children.

Voicing contrasts are lexically important for differentiating words in many languages (e.g., "bear" vs "pear"). Temporal differences in the voice onset time (VOT) and closure duration (CD) contribute to the voicing contrast in word-onset position. However, little is known about the acoustic realization of these voicing contrasts in Australian English-speaking children. This is essential for understanding the challenges faced by those with language delay. Therefore, the present study examined the VOT and CD values for word-initial stops as produced by 20 Australian English-speaking 4-5-year-olds. As anticipated, these children produced a systematic distinction between voiced and voiceless stops at all places of articulation (PoAs). However, although the children's VOT values for voiced stops were similar to those of adults, their VOTs for voiceless stops were longer. Like adults, the children also had different CD values for voiced and voiceless categories; however, these were systematically longer than those of adults. Even after adjusting for temporal differences by computing proportional ratios for the VOT and CD, children's voicing contrasts were not yet adultlike. These results suggest that children of this age are still developing appropriate timing and articulatory adjustments for voicing contrasts in the word-initial position.

Abstraction and the (Misnamed) Language Familiarity Effect.

Talkers are recognized more accurately if they are speaking the listeners' native language rather than an unfamiliar language. This "language familiarity effect" has been shown not to depend upon comprehension and must instead involve language sound patterns. We further examine the level of sound-pattern processing involved, by comparing talker recognition in foreign languages versus two varieties of English, by (a) English speakers of one variety, (b) English speakers of the other variety, and (c) non-native listeners (more familiar with one of the varieties). All listener groups performed better with native than foreign speech, but no effect of language variety appeared: Native listeners discriminated talkers equally well in each, with the native variety never outdoing the other variety, and non-native listeners discriminated talkers equally poorly in each, irrespective of the variety's familiarity. The results suggest that this talker recognition effect rests not on simple familiarity, but on an abstract level of phonological processing.

Phonologically determined asymmetries in vocabulary structure across languages.

Studies of spoken-word recognition have revealed that competition from embedded words differs in strength as a function of where in the carrier word the embedded word is found and have further shown embedding patterns to be skewed such that embeddings in initial position in carriers outnumber embeddings in final position. Lexico-statistical analyses show that this skew is highly attenuated in Japanese, a noninflectional language. Comparison of the extent of the asymmetry in the three Germanic languages English, Dutch, and German allows the source to be traced to a combination of suffixal morphology and vowel reduction in unstressed syllables.