Lexical-Semantic Cues Induce Sound Pattern Stability in Children With Developmental Language Disorder

I remembered the chorm! Word learning abilities of children with and without phonological impairment

BACKGROUND

Children with phonological impairment present with pattern-based errors in their speech production. While some children have difficulties with speech perception and/or the establishment of robust underlying phonological representations, the nature of phonological impairment in children is still not well understood. Given that phonological and lexical development are closely linked, one way to better understand the nature of the problem in phonological impairment is to examine word learning abilities in children.

AIMS

To examine word learning and its relationship with speech perception, speech production and vocabulary knowledge in children aged 4-5 years. There were two variables of interest: speech production abilities ranging from phonological impairment to typical speech; and vocabulary abilities ranging from typical to above average ('lexically precocious').

METHODS & PROCEDURES

Participants were 49 Australian-English-speaking children aged 48-69 months. Children were each taught four novel non-words (out of a selection of eight) through stories, and word learning was assessed at 1 week post-initial exposure. Word learning was assessed using two measures: confrontation naming and story retell naming. Data were analysed by group using independent-samples t-tests and Mann-Whitney U-tests, and continuously using multiple linear regression.

OUTCOMES & RESULTS

There was no significant difference in word learning ability of children with and without phonological impairment, but regardless of speech group, children with above average vocabulary had significantly better word learning abilities than children with average vocabulary. In multiple linear regression, vocabulary was the only significant predictor of variance in word learning ability.

CONCLUSIONS & IMPLICATIONS

Children with phonological impairment can be lexically precocious and learn new words like their peers without phonological impairment. Contrary to expectations, vocabulary knowledge rather than expressive phonological ability explained variance in measures of word learning. These findings question an assumption that children with phonological impairment have underspecified phonological representations. They also highlight the heterogeneity among children with phonological impairment and the need to better understand the nature of their difficulty learning the phonological system of the ambient language.

WHAT THIS PAPER ADDS

What is already known on the subject There is limited research examining the word learning abilities of children with phonological impairment. Most previous research focuses on word properties such as phonotactic probability and neighbourhood density. Within the existing literature there are different reports and conclusions regarding the word learning abilities of children with phonological impairment and whether their word learning differs from that of children with typically developing speech. What this study adds to existing knowledge This study found that vocabulary was the strongest predictor of word learning across children with and without phonological impairment. There was no significant difference in word learning ability between children with and without phonological impairment. However, children with lexically precocious vocabulary abilities were significantly better at word learning than children with average vocabulary abilities. What are the potential or actual clinical implications of this work? Findings from this study support the importance of assessing and considering measures of word learning-including vocabulary-when working with children with phonological impairment. This study indicates that it is possible to use stories coupled with measures of confrontation naming and story retell to gain deeper insight into children's word learning abilities.

The phonological congruency modulated long-term form priming of Chinese characters

Elucidating the interaction between lexical processing and word learning is essential for a complete understanding of the underlying mechanisms of each of them. Long-term priming for words reflects an interplay between lexical processing and word learning. Although robust long-term priming effects have been found between two occurrences of the same word and between semantically similar words, it remains unclear whether long-term priming between orthographically similar words (i.e., long-term form priming) is a reliable effect. Following the theoretical analysis based on the connectionist framework, we articulated the possibility that long-term form priming might be modulated by the phonological congruency between the prime and target words, and that if this modulator was under control, reliable effects of long-term form priming would emerge. However, this hypothesis has not been adequately tested empirically. The present study tested this hypothesis by using Chinese phonograms and the phonetic radicals embedded in them as the prime and target items. In three experiments that varied in the types of stimuli and testing tasks, we consistently found that when the prime and target had the same phonology, naming the prime facilitated later processing of the target, while when they had different phonologies, the priming effect was inhibitory. These observations were consistent with the connectionist account of long-term priming for words. Our findings help confirm the reliability, generalizability, and robustness of long-term form priming and elucidate its underlying mechanisms, and suggesting promising future directions on the interactions between lexical processing and word learning.

Children With Developmental Language Disorder Show Deficits in the Production of Musical Rhythmic Groupings

PURPOSE

Children with developmental language disorder (DLD) show evidence of domain-general deficits in sequentially patterned motor skills. This study focuses on the production of rhythmically grouped sequences drawn from a music task, with the hypothesis that children with DLD will show a sequential pattern learning deficit that crosses language and action domains.

METHOD

Fifty-seven 4- to 5-year-old children (36 with DLD) drummed and clapped a developmentally appropriate musical rhythmic sequence 24 times (clapped 12 times, drummed 12 times). The accuracy of rhythmic events (markings of claps, drums, and pauses in a target sequence) was assessed through a modification of classic speech and language transcription procedures. The variability and prosodic structure of the rhythmic groupings were also measured.

RESULTS

Children with DLD produced less accurate and more variable rhythmic groupings compared to their typically developing (TD) peers. While the final-position grouping of the sequence was especially vulnerable for all children, those with DLD included more co-occurring errors in initial and final groupings of the same rhythmic sequence. Both TD children and children with DLD were less accurate in the clapping than the drumming task. Neither rhythmic drumming nor clapping accuracy correlated with motor skill in either group of children.

CONCLUSIONS

This study provides novel evidence of a manual rhythmic grouping deficit in DLD, one that is motivated by language-not motor or speech-factors. Cognitive abilities necessary to organize rhythmic events into higher order groupings are impaired across music and language in children with DLD. Rhythmic organization and sequencing may serve an important role in diagnosis and intervention in this population.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24158745.

Acoustic and Kinematic Methods of Indexing Spatiotemporal Stability in Children With Developmental Language Disorder

PURPOSE

The spatiotemporal index (STI) is a standard metric for quantifying the stability and patterning of speech movements. The STI has often been applied to individual speech articulators, but an STI derived from the acoustic signal offers a composite and easily obtained measure that incorporates multiple components of the speech production complex. In this work, we examine the relationship between kinematic and acoustic STIs in children with and without developmental language disorder (DLD), with the aim of determining whether the acoustic and kinematic STIs reflect similar degrees of production variability.

METHOD

A total of 85 children with DLD and with typical language development (or typically developing [TD] children), aged 4-8 years, were studied. In this methodological article, two experiments were conducted: one deliberately selected because group differences were observed in the kinematic STI (i.e., sentence production) and one in which there were no group differences in the kinematic STI (i.e., nonword production). These two experiments are representative of speech stability studies. The aim was to determine whether the acoustic STI (i.e., amplitude envelope) results aligned with those obtained via the kinematic STI (i.e., lip motion).

RESULTS

In sentence production, most group differences aligned across kinematic and acoustic STI measures. The acoustic, but not the kinematic, STI showed higher variability in children with DLD compared with the 6-year-old TD group. In nonword production, neither the kinematic STI nor the acoustic STI differentiated children with DLD from TD children. In each experiment, the kinematic and acoustic STIs showed a moderate-to-strong correlation.

CONCLUSIONS

The kinematic and acoustic STIs assess different components of speech movement patterning. However, the relationship between acoustic and kinematic spatiotemporal stability is strong in two tasks of varying linguistic complexity in children with and without DLD. These findings are promising for future experimental work in this area.

Phonological and Articulatory Deficits in the Production of Novel Signs in Children With Developmental Language Disorder

PURPOSE

Sign language, like spoken language, incorporates phonological and articulatory (or motor) processing components. Thus, the learning of novel signs, like novel spoken word forms, may be problematic for children with developmental language disorder (DLD). In the present work, we hypothesize that phonological and articulatory deficits in novel sign repetition and learning would differentiate preschool-age children with DLD from their typical peers.

METHOD

Children with DLD (n = 34; aged 4-5 years) and their age-matched typical peers (n = 21) participated. Children were exposed to four novel signs, all iconic, but only two linked to a visual referent. Children imitatively produced these novel signs multiple times. We obtained measures of phonological accuracy and articulatory motion stability as well as of learning of the associated visual referent.

RESULTS

Children with DLD showed an increased number of phonological feature (i.e., handshape, path, and orientation of the hands) errors when compared with their typical peers. While articulatory variability did not overall differentiate children with DLD from typical peers, children with DLD showed instability in one novel sign that obligated bimanual oppositional movement. Semantic aspects of novel sign learning were unaffected in children with DLD.

CONCLUSIONS

Deficits that have been documented in phonological organization of spoken words in children with DLD are also evident in the manual domain. Analyses of hand motion variability suggest that children with DLD do not show a generalized motor deficit, but one that is restricted to the implementation of coordinated and sequential hand motion.

A longitudinal study of the phonological organisation of novel word forms in children with developmental language disorder

Purpose: Deficits in the production of novel words, such as in nonword repetition tasks, are one of the early hallmarks of developmental language disorder (DLD). In children with DLD, the production of novel nonwords is characterised by speech sound inaccuracy. The focus of the present study is on the stable organisation of phonological sequences. Specifically, we aimed to identify the persistence of deficits in accuracy and in variability in sound sequencing in novel word production from pre-school to the early school years.Method: Children with and without DLD produced a set of six nonwords 12 times each, initially collected when children were 4- to 5-years old. Children repeated this task over the course of two years. Analyses included phonetic accuracy as well as network science indices of sound sequence organisation.Result: Children with DLD were less accurate than their peers with typical language at each timepoint, and their productions were markedly variable, as revealed by network science metrics; these children never converged with their peers with typical language.Conclusion: The findings suggest a unique deficit in phonological sequence production that persists beyond the pre-school years. These results offer new theoretical and clinical insights into mechanisms that underlie deficits in novel word form learning.

Word Learning by Preschool-Age Children With Developmental Language Disorder: Impaired Encoding and Robust Consolidation During Slow Mapping

Purpose Learning novel words, including the specific phonemes that make up word forms, is a struggle for many individuals with developmental language disorder (DLD). Building robust representations of words includes encoding during periods of input and consolidation between periods of input. The primary purpose of the current study is to determine differences between children with DLD and with typical development (TD) in the encoding and consolidation of word forms during the slow mapping process. Method Preschool-age children (DLD = 9, TD = 9) were trained on nine form-referent pairs across multiple consecutive training days. Children's ability to name referents at the end of training days indicated their ability to encode forms. Children's ability to name referents at the beginning of training days after a period of overnight sleep indicated their ability to consolidate forms. Word learning was assessed 1 month after training to determine long-term retention of forms. Results Throughout training, children with DLD produced fewer forms correctly and produced forms with less phonological precision than children with TD. Thus, children with DLD demonstrated impaired encoding. However, children with and without DLD demonstrated a similar ability to consolidate forms between training days and to retain forms across a 1-month delay. Conclusions Difficulties with word form learning are primarily driven by deficits in encoding for children with DLD. Clinicians and educators can support encoding by providing children with adequate exposures to target words via robust training that occurs across multiple sessions. Supplemental Material https://doi.org/10.23641/asha.16746454.