Uncovering the development of linguistic knowledge in lesser studied languages.

There has recently been an increased interest in studying the language development of non-western languages. This is not new - it began in 1960's and continued into the 1980's and 1990's. The current renewed interest is much welcomed, and will benefit from many of the experimental methods and theoretical insights developed over the past decades.

Effects of maternal depression on maternal responsiveness and infants' expressive language abilities.

High levels of maternal responsiveness are associated with healthy cognitive and emotional development in infants. However, depression and anxiety can negatively impact individual mothers' responsiveness levels and infants' expressive language abilities. Australian mother-infant dyads (N = 48) participated in a longitudinal study examining the effect of maternal responsiveness (when infants were 9- and 12-months), and maternal depression and anxiety symptoms on infant vocabulary size at 18-months. Global maternal responsiveness ratings were stronger predictors of infants' vocabulary size than levels of depression and anxiety symptoms. However, depression levels moderated the effect of maternal responsiveness on vocabulary size. These results highlight the importance of screening for maternal responsiveness-in addition to depression-to identify infants who may be at developmental risk. Also, mothers with elevated depression need support to first reduce their symptoms so that improvements in their responsiveness have the potential to be protective for their infant's language acquisition.

The acquisition of contrastive focus during online sentence-comprehension by children learning mandarin Chinese.

Contrastive focus, conveyed by prosodic cues, marks important information. Studies have shown that 6-year-olds learning English and Japanese can use contrastive focus during online sentence comprehension: focus used in a contrastive context facilitates the identification of a target referent (speeding up processing), whereas focus used inappropriately in a noncontrastive context misleads listeners to predict an incorrect referent, hindering the identification process (Ito et al., 2012, 2014). In Mandarin Chinese, the mapping between prosodic form and contrastive focus is less transparent, potentially delaying the acquisition of contrastive focus. This study assessed the online processing of contrastive focus by 196 Mandarin-speaking 4-10-year-olds and 34 adults in China, using the visual world paradigm. Stimuli contained a target NP in a mini discourse, with focus being used in contrastive (Experiment 1) versus Noncontrastive contexts (Experiment 2). Experiment 1 showed that the appropriate use of prosodic form for contrastive focus facilitated the identification of a target referent for 7-10-year-olds and adults, though not younger children. Experiment 2 showed that the inappropriate use of prosodic form for contrastive focus slowed the identification process only for 10-year-olds and adults. Thus, whereas 7-10-year-olds are sensitive to prosodic form for contrastive focus, only 10-year-olds use it as a primary cue to predict an upcoming referent like adults. The acquisition of contrastive focus in Mandarin is therefore a gradual process, with children showing sensitivity to contrastive focus during the early school years, and developing adult-like form-function mapping between prosody and focus until the end of primary school. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

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.

Children with hearing loss can use subject-verb agreement to predict during spoken language processing.

Rapid processing of spoken language is aided by the ability to predict upcoming words using both semantic and syntactic cues. However, although children with hearing loss (HL) can predict upcoming words using semantic associations, little is known about their ability to predict using syntactic dependencies such as subject-verb (SV) agreement. This study examined whether school-aged children with hearing aids and/or cochlear implants can use SV agreement to predict upcoming nouns when processing spoken language. Although they did demonstrate prediction with plural SV agreement, they did so more slowly than their normal hearing (NH) peers. This may be due to weaker grammatical representations given that function words and grammatical inflections typically have lower perceptual salience. Thus, a better understanding of morphosyntactic representations in children with HL, and their ability to use these for prediction, sheds much-needed light on the online language processing challenges and abilities of this population.

The acoustic realization of contrastive focus by 6-year-old Australian English-speaking children.

Children as young as five have some ability to produce contrastive focus [Wells et al. (2004) J. Child Lang. 31, 749-778]. However, adult listeners' ability to identify the location of contrastive focus depends on whether the speech came from a 4-, 7-, or 11-year-old [Patel and Brayton (2009) J. Speech. Lang. Hear. Res. 52, 790-801]. Recent acoustic studies have also reported the use of F0 vs duration in contrastive focus productions by American English-speaking 2-year-olds [Thorson and Morgan (2021) J. Child Lang. 48, 541-568] and 4-year-olds [Wonnacott and Watson (2008) Cognition 107, 1093-1101], respectively. This study, therefore, evaluated the extent to which older 6-year-olds, with more language experience, used F0 and/or duration when producing contrastive focus, and compared this to adult speech. Monosyllabic and disyllabic adjective + noun targets (e.g., green ball) in utterance medial and final position were elicited from 20 Australian English-speaking 6-year-olds and 14 adults in adjective focus and noun focus conditions. Although both adults and children used high F0, only adults consistently used word and stressed syllable duration as well. This suggests that children may master the different acoustic cues to contrastive focus at different stages of development, with late cue integration.

Produced, but not 'productive': Mandarin-speaking pre-schoolers' challenges acquiring L2 English plural morphology.

It is often assumed that pre-schoolers learn a second language (L2) with ease, even for structures that are absent in their L1, such as Mandarin-speaking pre-schoolers learning L2 English grammatical inflections (e.g., ducks, horses). However, while the results from Study 1 showed that such learners can imitate plural words (age = 3;5, N = 20), Studies 2 and 3 showed that they cannot yet generate or comprehend plural morphology (Study 2: age = 4;8, N = 20; Study 3: age = 4;1, N = 20), raising questions about when this is achieved. These findings have important implications for school readiness, as well as for identifying those at risk of developmental language disorders.

Jellybeans or Jelly, Beans ? 5-6-year-olds can identify the prosody of compounds but not lists.

Learning to use word versus phrase level prosody to identify compounds from lists is thought to be a protracted process, only acquired by 11 years (Vogel & Raimy, 2002). However, a recent study has shown that 5-year-olds can use prosodic cues other than stress for these two structures in production, at least for early-acquired noun-noun compounds (Yuen et al., 2021). This raises the question of whether children this age can also use naturally-produced prosody to identify noun-noun compounds from their list forms in comprehension. The results show that 5-6-year-olds (N = 28) can only identify compounds. Unlike adults, children as a group could not use boundary cues to identify lists and were significantly slower in their processing compared to adults. This suggests that the acquisition of word level prosody may precede the acquisition of phrase level prosody, i.e., some higher-level aspects of phrasal prosody may take longer to acquire.

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.

Child-directed and overheard input from different speakers in two distinct cultures.

Despite the fact that in most communities interaction occurs between the child and multiple speakers, most previous research on input to children focused on input from mothers. We annotated recordings of Sesotho-learning toddlers living in non-industrial Lesotho in South Africa, and French-learning toddlers living in urban regions in France. We examined who produced the input (mothers, other children, adults), how much input was child directed, and whether and how it varied across speakers. As expected, mothers contributed most of the input in the French recordings. However, in the Sesotho recordings, input from other children was more common than input from mothers or other adults. Child-directed speech from all speakers in both cultural groups showed similar qualitative modifications. Our findings suggest that input from other children is prevalent and has similar features as child-directed from adults described in previous work, inviting cross-cultural research into the effects of input from other children.

Longer Cochlear Implant Experience Leads to Better Production of Mandarin Tones for Early Implanted Children.

OBJECTIVES: Children with cochlear implants (CIs) face challenges in acquiring tones, since CIs do not transmit pitch information effectively. It has been suggested that longer CI experience provides additional benefits for children implanted early, enabling them to achieve language abilities similar to that of normal-hearing (NH) children (Colletti 2009). Mandarin is a tonal language with four lexical tones and a neutral tone (T0), characterized by distinct pitch and durational patterns. It has been suggested that early implantation (i.e., before 2 years) greatly benefits the acquisition of Mandarin tones by children with CIs (Tang et al. 2019c). In this study, we extend those findings to investigate the effect of CI experience on the acquisition of Mandarin tones for children implanted early. We asked the extent to which they were able to produce distinct pitch and durational patterns of both lexical tones and T0 as a function of CI experience, and the extent to which their tonal productions were acoustically like that of NH children. DESIGN: Forty-four NH 3-year olds and 28 children implanted with CIs between 1 and 2 years, aged 3 to 7, were recruited. The children with CIs were grouped according to the length of CI experience: 3 to 6 years, 2 to 3 years, and 1 to 2 years. Lexical tone and T0 productions were elicited using a picture-naming task. Tonal productions from the children with CIs were acoustically analyzed and compared with those from the NH children. RESULTS: Children with 3 to 6 years of CI experience were able to produce distinct pitch and durational patterns for both lexical tones and T0, with NH-like acoustic realizations. Children with 2 to 3 years of CI experience were also able to produce the expected tonal patterns, although their productions were not yet NH-like. Those with only 1 to 2 years of CI experience, however, were not yet able to produce the distinct acoustic patterns for either lexical tones or T0. CONCLUSIONS: These results provide acoustic evidence demonstrating that, when Mandarin-speaking children are implanted before the age of 2, only those with 3 to 6 years of experience were able to produce NH-like tones, including both lexical tone and T0. Children with shorter CI experience (less than 3 years) were unable to produce distinct acoustic patterns for the different tones. This suggests that at least 3 years of CI experience is still needed for early implanted children to acquire tonal distinctions similar to those of NH 3-year olds.

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.

Five-year-olds produce prosodic cues to distinguish compounds from lists in Australian English.

Although previous research has indicated that five-year-olds can use acoustic cues to disambiguate compounds (N1 + N2) from lists (N1, N2) (e.g., 'ice-cream' vs. 'ice, cream') (Yoshida & Katz, 2004, 2006), their productions are not yet fully adult-like (Wells, Peppé & Goulandris, 2004). The goal of this study was to examine this issue in Australian English-speaking children, with a focus on their use of F0, word duration, and pauses. Twenty-four five-year-olds and 20 adults participated in an elicited production experiment. Like adults, children produced distinct F0 patterns for the two structures. They also used longer word durations and more pauses in lists compared to compounds, indicating the presence of a boundary in lists. However, unlike adults, they also inappropriately inserted more pauses within the compound, suggesting the presence of a boundary in compounds as well. The implications for understanding children's developing knowledge of how to map acoustic cues to prosodic structures are discussed.

Is One Ear Good Enough? Unilateral Hearing Loss and Preschoolers' Comprehension of the English Plural.

Purpose The plural is one of the first grammatical morphemes acquired by English-speaking children with normal hearing (NH). Yet, those with hearing loss show delays in both plural comprehension and production. However, little is known about the effects of unilateral hearing loss (UHL) on children's acquisition of the plural, where children's ability to perceive fricatives (e.g., the /s/ in cats ) can be compromised. This study therefore tested whether children with UHL were able to identify the grammatical number of newly heard words, both singular and plural. Method Eleven 3- to 5-year-olds with UHL participated in a novel word two-alternative forced choice task presented on an iPad. Their results were compared to those of 129 NH 3- to 5-year-olds. During the task, children had to choose whether an auditorily presented novel word was singular (e.g., tep, koss) or plural (e.g., teps, kosses) by touching the appropriate novel picture. Results Like their NH peers, children with UHL demonstrated comprehension of novel singulars. However, they were significantly less accurate at identifying novel plurals, with performance at chance. However, there were signs that their ability to identify novel plurals may improve with age. Conclusion While comparable to their NH peers at identifying novel singulars, these results suggest that young children with UHL do not yet have a robust representation of plural morphology, particularly on words they have not encountered before.

Maternal Depression Affects Infants' Lexical Processing Abilities in the Second Year of Life.

Maternal depression and anxiety have been proposed to increase the risk of adverse outcomes of language development in the early years of life. This study investigated the effects of maternal depression and anxiety on language development using two approaches: (i) a categorical approach that compared lexical abilities in two groups of children, a risk group (mothers with clinical-level symptomatology) and a control non-risk group, and (ii) a continuous approach that assessed the relation between individual mothers' clinical and subclinical symptomatology and their infants' lexical abilities. Infants' lexical abilities were assessed at 18 months of age using an objective lexical processing measure and a parental report of expressive vocabulary. Infants in the risk group exhibited lower lexical processing abilities compared to controls, and maternal depression scores were negatively correlated to infants' lexical processing and vocabulary measures. Furthermore, maternal depression (not anxiety) explained the variance in infants' individual lexical processing performance above the variance explained by their individual expressive vocabulary size. These results suggest that significant differences are emerging in 18-month-old infants' lexical processing abilities, and this appears to be related, in part, to their mothers' depression and anxiety symptomatology during the postnatal period.

Dichotic listening is associated with phonological awareness in Australian aboriginal children with otitis media: A remote community-based study.

OBJECTIVE: Recent literature has highlighted a link between hearing loss as a result of otitis media in the early years of life and impacted binaural processing skills in later childhood. Such findings are of particular relevance to Indigenous Australian children, who tend to experience otitis media earlier in life and for longer periods than their non-Indigenous counterparts. There is also growing interest in the effects of reduced auditory processing ability on a child's early learning of language and, specifically, on phonological awareness that contributes to word reading skills. The aim of the present study was to determine the association between hearing thresholds, dichotic listening skills and phonological awareness in children with pervasive otitis media (OM) from remote Indigenous communities of Australia who generally do not speak English as a first language. METHODS: Participants included one hundred and one children between the ages of 4.8-7.9 years (mean 6.1 years) from three separate remote Northern Territory communities. Evaluations included otoscopy, air conduction PTA, and tympanometry. All children were also assessed on the Dichotic Digits difference test (DDdT) and the Foundations of Early Literacy Assessment (FELA), assessing children's dichotic listening and phonological awareness respectively. RESULTS: The results showed that 56% of the children had middle ear dysfunctions (type B and type C on tympanometry results) in at least one ear on the day. Partial correlation showed a significant correlation, between dichotic scores and FELA with age as covariate (r = 0.45, p < 0.001). One way ANOVA showed females exhibited a significantly higher performance compared to males on FELA [F (1, 99) = 5.47, p = 0.021]. The overall regression model was found to be significant in predicting total FELA scores [F (7, 77) = 7.56, p < 0.0005]. Age and gender as well as dichotic listening scores explain 40.7% of the variance. CONCLUSIONS: The results reinforce the importance of managing the ear health of Indigenous children, clarifying the impact this has on listening and phonological awareness. These findings highlight the importance of evaluating children's listening abilities, and how poor listening can impact phonological awareness. The findings have important implications for ensuring optimal listening and learning conditions in schools in remote NT communities.

Depression and Anxiety in the Postnatal Period: An Examination of Infants' Home Language Environment, Vocalizations, and Expressive Language Abilities.

This longitudinal study investigated the effects of maternal emotional health concerns, on infants' home language environment, vocalization quantity, and expressive language skills. Mothers and their infants (at 6 and 12 months; 21 mothers with depression and or anxiety and 21 controls) provided day-long home-language recordings. Compared with controls, risk group recordings contained fewer mother-infant conversational turns and infant vocalizations, but daily number of adult word counts showed no group difference. Furthermore, conversational turns and infant vocalizations were stronger predictors of infants' 18-month vocabulary size than depression and anxiety measures. However, anxiety levels moderated the effect of conversational turns on vocabulary size. These results suggest that variability in mothers' emotional health influences infants' language environment and later language ability.

The Acquisition of Productive Plural Morphology by Children With Hearing Loss.

Purpose Normal-hearing (NH) children acquire plural morphemes at different rates, with the segmental allomorphs /-s, -z/ (e.g., cat-s) being acquired before the syllabic allomorph /-əz/ (e.g., bus-es). Children with hearing loss (HL) have been reported to show delays in the production of plural morphology, raising the possibility that this might be due to challenges acquiring different types of lexical/morphological representations. This study therefore examined the comprehension of plural morphology by 3- to 7-year-olds with HL and compared this with performance by their NH peers. We also investigated comprehension as a function of wearing hearing aids (HAs) versus cochlear implants (CIs). Method Participants included 129 NH children aged 3-5 years and 25 children with HL aged 3-7 years (13 with HAs, 12 with CIs). All participated in a novel word two-alternative forced-choice task presented on an iPad. The task tested comprehension of the segmental (e.g., teps, mubz) and syllabic (e.g., kosses) plural, as well as their singular counterparts (e.g., tep, mub, koss). Results While the children with NH were above chance for all conditions, those with HL performed at chance. As a group, the performance of the children with HL did not improve with age. However, results suggest possible differences between children with HAs and those with CIs, where those with HAs appeared to be in the process of developing representations of consonant-vowel-consonant singulars. Conclusions Results suggest that preschoolers with HL do not yet have a robust representation of plural morphology for words they have not heard before. However, those with HAs are beginning to access the singular/plural system as they get older.