Working memory and novel word learning in children with hearing impairment and children with specific language impairment

The Effect of Background Noise, Bilingualism, Socioeconomic Status, and Cognitive Functioning on Primary School Children's Narrative Listening Comprehension

PURPOSE

This study focuses on 7- to 9-year-old children attending primary school in Swedish areas of low socioeconomic status, where most children's school language is their second language. The aim was to better understand what factors influence these children's narrative listening comprehension both in an ideal listening condition (in quiet) and for the primary school classroom, a typical listening condition (with multitalker babble noise).

METHOD

A total of 86 typically developing 7- to 9-year-olds performed a narrative listening comprehension test (Lyssna, Förstå och Minnas [LFM]; English translation: Listen, Comprehend, and Remember) in two listening conditions: quiet and multitalker babble noise. They also performed the crosslinguistic nonword repetition test and a digit span backwards (DSB) test. A predictive statistical model including these factors, the children's degree of school language exposure, parental education level, and age was derived.

RESULTS

Listening condition had the strongest predictive value for LFM performance, followed by school language exposure and nonword repetition accuracy. Parental education level was also a significant predictor. There was a significant three-way interaction effect between listening condition, age, and DSB performance.

CONCLUSIONS

Multitalker babble noise has a negative effect on children's narrative listening comprehension. The effect of multitalker babble noise could be explained by age differences in the ability to allocate working memory capacity during the narrative listening comprehension task, suggesting that younger children may be more vulnerable for missing information when listening in background noise than their older peers.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.25209248.

Reading Comprehension of Chinese-Speaking Children With Hearing Loss: The Roles of Metalinguistic Awareness and Vocabulary Knowledge

PURPOSE

This study aims to explore the contributions of phonological awareness (PA) and morphological awareness (MA) to the reading comprehension skills of Chinese-speaking children with hearing loss (HL) and examine the possible mediation effect of vocabulary knowledge on the relationships of PA and MA with their reading comprehension.

METHOD

The participants were 28 Chinese-speaking children with HL, who were followed from Grade 1 through Grade 2. They were administered a series of tests that measured their PA and MA at the beginning of Grade 1, vocabulary knowledge at the end of Grade 1, and reading comprehension at the end of Grade 2.

RESULTS

MA significantly accounted for additional variance in reading comprehension beyond the effect of PA but not vice versa. Both PA and MA contributed uniquely to vocabulary knowledge, which completely mediated the relationships of PA and MA with reading comprehension.

CONCLUSIONS

PA and MA are both essential to the development of vocabulary knowledge and reading comprehension in Chinese-speaking children with HL; however, MA seems to be more important than PA in their reading comprehension. PA and MA significantly affect children's reading comprehension through their influence on vocabulary knowledge. This study has replicated previous evidence on the importance of PA, MA, and vocabulary knowledge in the reading comprehension of children with typical hearing, and has extended its significance to children with HL. In addition, the findings have the potential to inform educational practitioners regarding the importance of teaching essential reading skills to Chinese-speaking children with HL.

Spectral degradation influences phonological memory in typically hearing adults

Phonological processing is a fundamental component of language, can be impaired in people with hearing loss, and involves several confounded subprocesses. The purpose of this study was to systematically examine several phonological subprocesses - i.e., the spectral quality of auditory input and phonological short-term and long-term memory - in order to better understand how they interact with one another in basic linguistic tasks. Using an experimental, within-subjects design, 30 typically-hearing adults completed nonword repetition (NWR) and auditory lexical decision (ALD) tasks varying in spectral quality (normal versus spectrally-degraded), consonant age of acquisition (CAoA; i.e. early-acquired versus late-acquired consonants), syllable length (NWR task), and lexical status (ALD task). In NWR, spectral degradation muted the word length effect, though performance differed depending on how familiar participants were with the degraded stimuli. ALD findings showed that the magnitude of the degradation effect varied between stimuli comprising early-acquired versus late-acquired consonants. The robust effect of spectral degradation on phonological short-term and long-term memory provides a model of the interactive nature of these subprocesses in typical adults. Future work with populations with hearing loss can provide a comparison to help understand how the typical and clinical phonological systems differ.

Auditory Experience, Speech Sound Production Growth, and Early Literacy in Children Who Are Hard of Hearing

PURPOSE

Children who are hard of hearing (CHH) are at risk for literacy difficulties. Speech sound production is related to literacy skills in typically hearing children. Speech sound production abilities can also be markedly weak in CHH due to inconsistent access to the speech signal. We longitudinally examined relations between auditory experience, speech sound production abilities, and literacy (i.e., nonword reading and spelling in second grade) in CHH.

METHOD

Participants included 166 CHH. All participants used hearing aids (HAs). Auditory experience is a weighted measure of the number of hours of daily HA use and the amount of audibility with and without their HAs. Children's speech sound production was tested 2-3 times between the ages of 3 and 9 years. At age 5 years and again in second grade, children were tested on a battery of language and literacy measures.

RESULTS

Auditory experience was significantly correlated with speech sound production abilities, but age at HA fitting was not. Speech sound production abilities at age 5 years did not predict nonword reading in second grade but did predict spelling skills in second grade.

CONCLUSIONS

Our results support the importance of auditory experience and speech sound production for later literacy abilities. Specifically, we found that speech sound production abilities and print knowledge at age 5 years are related to second grade spelling outcomes. Interestingly, we found that morphological knowledge at age 5 years was more predictive of decoding in second grade than was speech sound production. Although there are multiple factors that contribute to literacy success, our results underscore the unique contributions of speech sound production abilities in CHH.

Best ear hearing level, time factors and language outcome in Swedish children with mild and moderate hearing loss with hearing aids

AIM

The risk for language disorder is high in children with all levels of hearing loss (HL). Early identification and intervention should be as important for children with mild HL as for those with more severe HL. Despite new-born hearing screening, a recent survey of speech language therapist services in southern Sweden indicates that children with mild and moderate HL are severely neglected when it comes to language assessment and language intervention. In this study we explore associations between Best Ear Hearing Level (BEHL), time factors and language skills in Swedish children with HL with hearing aids (HA).

METHOD

Participants were 19 children with mild HL (BEHL 23-39) and 22 children with moderate HL (BEHL 40-70) aged 5-15 years. Information on age at diagnosis and at HA fitting were collected. The children performed a nonword repetition and a sentence comprehension task.

RESULTS

The time elapsed between diagnosis and fitting with HA was longer for the children with mild HL.Participants with mild HL received their HA significantly later than children with moderate HL. No association between BEHL and the two language measures was found, and language skills were not better in children with mild than moderate HL. 17% of participants performed below cut-off for language disorder on both language measures.

CONCLUSION

Given the risk for long-term academic and social consequences of even mild HL delayed HA intervention for children with HLleads to serious concerns by families, clinicians, and pedagogues.

Short-Term Pediatric Acclimatization to Adaptive Hearing Aid Technology

Purpose This exploratory study assessed the perceptual, cognitive, and academic learning effects of an adaptive, integrated, directionality, and noise reduction hearing aid program in pediatric users. Method Fifteen pediatric hearing aid users (6-12 years old) received new bilateral, individually fitted Oticon Opn hearing aids programmed with OpenSound Navigator (OSN) processing. Word recognition in noise, sentence repetition in quiet, nonword repetition, vocabulary learning, selective attention, executive function, memory, and reading and mathematical abilities were measured within 1 week of the initial hearing aid fitting and 2 months post fit. Caregivers completed questionnaires assessing their child's listening and communication abilities prior to study enrollment and after 2 months of using the study hearing aids. Results Caregiver reporting indicated significant improvements in speech and sound perception, spatial sound awareness, and the ability to participate in conversations. However, there was no positive change in performance in any of the measured skills. Mathematical scores significantly declined after 2 months. Conclusions OSN provided a perceived improvement in functional benefit, compared to their previous hearing aids, as reported by caregivers. However, there was no positive change in listening skills, cognition, and academic success after 2 months of using OSN. Findings may have been impacted by reporter bias, limited sample size, and a relatively short trial period. This study took place during the summer when participants were out of school, which may have influenced the decline in mathematical scores. The results support further exploration with age- and audiogram-matched controls, larger sample sizes, and longer test-retest intervals that correspond to the academic school year.

Word learning and verbal working memory in children with developmental language disorder

BACKGROUND AND AIMS

Previous research into word learning in children with developmental language disorder (DLD) indicates that the learning of word forms and meanings, rather than form-referent links, is problematic. This difficulty appears to arise with impaired encoding, while retention of word knowledge remains intact. Evidence also suggests that word learning skills may be related to verbal working memory. We aimed to substantiate these findings in the current study by exploring word learning over a series of days.

METHODS

Fifty children with DLD (mean age 6; 11, 72% male) and 54 age-matched typically developing (TD) children (mean age 6; 10, 56% male) were taught eight novel words across a four-day word learning protocol. Day 1 measured encoding, Days 2 and 3 measured re-encoding, and Day 4 assessed retention. At each day, word learning success was evaluated using Naming, Recognition, Description, and Identification tasks.

RESULTS

Children with DLD showed comparable performance to the TD group on the Identification task, indicating an intact ability to learn the form-referent links. In contrast, children with DLD performed significantly worse for Naming and Recognition (signifying an impaired ability to learn novel word forms), and for Description, indicating problems establishing new word meanings. These deficits for the DLD group were apparent at Days 1, 2, and 3 of testing, indicating impairments with initial encoding and re-encoding; however, the DLD and TD groups demonstrated a similar rate of learning. All children found the retention assessments at Day 4 difficult, and there were no significant group differences. Finally, verbal working memory emerged as a significant moderator of performance on the Naming and Recognition tasks, such that children with DLD and poor verbal working memory had the lowest levels of accuracy.

CONCLUSIONS

This study demonstrates that children with DLD struggle with learning novel word forms and meanings, but are unimpaired in their ability to establish new form-referent links. The findings suggest that the word learning deficit may be attributed to problems with encoding, rather than with retention, of new word knowledge; however, further exploration is required given the poor performance of both groups for retention testing. Furthermore, we found evidence that an impaired ability to learn word forms may only be apparent in children who have DLD and low levels of verbal working memory.

IMPLICATIONS

When working with children with DLD, speech-language pathologists should assess word learning using tasks that evaluate the ability to learn word forms, meanings, and form-referent links to develop a profile of individual word learning strengths and weaknesses. Clinicians should also assess verbal working memory to identify children at particular risk of word learning deficits. Future research should explore the notion of optimal intervention intensity for facilitating word learning in children with poor language and verbal working memory.

Description and prediction of reading decoding skills in Swedish children with Developmental Language Disorder

AIM

Research is lacking in terms of reading decoding skills among clinical samples of Swedish-speaking children with Developmental Language Disorder (DLD).

METHOD

The present cross-sectional study included a sample of 61 children (8-12 years) with DLD attending school language units, years 1 to 5. Our purpose was to study reading decoding skills and predictors for decoding, such as a phonological processing skill (nonword repetition), working memory, and a family history of literacy problems.

RESULTS

The results on a combined measure of the word and nonword decoding indicated that only 18% of the children had age-adequate decoding skills. The proportion of age-adequate decoders did not change noticeably with the school year. The participants' decoding skills showed larger deviations to test norm means with higher school years. Hierarchical regression analysis showed that the best predictors of decoding skills were measures of working memory and nonword repetition, followed by school year. These factors significantly contributed to the variance in decoding among our sample of children with DLD. A family history of literacy problems made no contribution to the variance. Conclusions: The findings emphasize the necessity of assessing and following up on literacy development in children with DLD.

Cerebral volume and diffusion MRI changes in children with sensorineural hearing loss

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Microstructural and macrostructural changes in sensorineural hearing loss.

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Magnetic resonance imaging as tool to assess cerebral volume and diffusion.

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Greater diffusion in cortex, thalamus, caudate, brainstem with hearing loss.

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Smaller brainstem volume with hearing loss.

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Connexin 26, Pendrin mutations show diffusion changes in brainstem and thalamus.

Purpose

Sensorineural hearing loss (SNHL) is the most prevalent congenital sensory deficit in children. Information regarding underlying brain microstructure could offer insight into neural development in deaf children and potentially guide therapies that optimize language development. We sought to quantitatively evaluate MRI-based cerebral volume and gray matter microstructure children with SNHL.

Methods & Materials

We conducted a retrospective study of children with SNHL who obtained brain MRI at 3 T. The study cohort comprised 63 children with congenital SNHL without known focal brain lesion or structural abnormality (33 males; mean age 5.3 years; age range 1 to 11.8 years) and 64 age-matched controls without neurological, developmental, or MRI-based brain macrostructure abnormality. An atlas-based analysis was used to extract quantitative volume and median diffusivity (ADC) in the following brain regions: cerebral cortex, thalamus, caudate, putamen, globus pallidus, hippocampus, amygdala, nucleus accumbens, brain stem, and cerebral white matter. SNHL patients were further stratified by severity scores and hearing loss etiology.

Results

Children with SNHL showed higher median ADC of the cortex (p = .019), thalamus (p < .001), caudate (p = .005), and brainstem (p = .003) and smaller brainstem volumes (p = .007) compared to controls. Patients with profound bilateral SNHL did not show any significant differences compared to patients with milder bilateral SNHL, but both cohorts independently had smaller brainstem volumes compared to controls. Children with unilateral SNHL showed greater amygdala volumes compared to controls (p = .021), but no differences were found comparing unilateral SNHL to bilateral SNHL. Based on etiology for SNHL, patients with Pendrin mutations showed higher ADC values in the brainstem (p = .029, respectively); patients with Connexin 26 showed higher ADC values in both the thalamus (p < .001) and brainstem (p < .001) compared to controls.

Conclusion

SNHL patients showed significant differences in diffusion and volume in brain subregions, with region-specific findings for patients with Connexin 26 and Pendrin mutations. Future longitudinal studies could examine macro- and microstructure changes in children with SNHL over development and potential predictive role for MRI after interventions including cochlear implant outcome.

The Impact of Dose and Dose Frequency on Word Learning by Kindergarten Children With Developmental Language Disorder During Interactive Book Reading

Purpose

The goal was to determine whether interactive book reading outcomes for children with developmental language disorder (DLD) were affected by manipulation of dose (i.e., the number of exposures to the target word during a book reading session) and dose frequency (i.e., the number of repeated book reading sessions) and whether pretreatment factors predicted treatment response variation.

Method

Thirty-four kindergarten children with DLD (aged 5;0–6;2 [years;months]) were taught 1 set of words using the Dose 6 and Dose Frequency 6 format from a prior study (Storkel, Voelmle, et al., 2017) and taught a different set of words using an alternative format, either Dose 4 × Dose Frequency 9 or Dose 9 × Dose Frequency 4, determined through random assignment. Word learning was tracked for each treatment via a definition task prior to, during, and after treatment.

Results

Results showed that children with DLD learned a significant number of words during treatment regardless of the dose and dose frequency format but that significant forgetting of newly learned words occurred in all formats once treatment was withdrawn. Individual differences in word learning were related to Clinical Evaluation of Language Fundamentals Core Language and Understanding Spoken Paragraphs scores.

Conclusion

When administered at an adequate intensity, variation in the dose and dose frequency of interactive book reading does not appear to influence word learning by children with DLD. Although interactive book reading continues to show promise as an effective word learning intervention for children with DLD, further development is needed to enhance the effectiveness of this treatment approach.

Supplemental Material

https://doi.org/10.23641/asha.9745181

Effects of Signs on Word Learning by Children With Developmental Language Disorder

Purpose This study investigated the effects of signs on word learning by children with developmental language disorder (DLD), in comparison with typically developing (TD) children, and the relation between a possible sign effect and children's linguistic and cognitive abilities. Method Nine- to 11-year-old children with DLD ( n = 40) and TD children ( n = 26) participated in a word learning experiment. Half of the spoken pseudowords were taught with a pseudosign with learning outcomes being assessed in accuracy and speed. To investigate whether sign effects would hold for children with varying linguistic and cognitive abilities, we measured children's linguistic (vocabulary, syntax) and cognitive (divided attention, working memory [WM], lexical access) skills. Results The children with DLD showed a positive sign effect in both accuracy and speed. For the TD children, there was no effect of signs on word learning. Principal component analyses of the linguistic and cognitive measures evidenced a 4-component solution (language skills, visual WM, verbal WM, and executive attention). Repeated-measures analyses of covariance with the component scores as covariates yielded no significant interactions with the linguistic and cognitive components. Conclusions Our results suggest that children with DLD benefit from signs for word learning, regardless of their linguistic and cognitive abilities. This implies that using sign-supported speech as a means to improve the vocabulary skills of children with DLD is effective, even still at the age of 9-11 years.

Latent Semantic Analysis Discriminates Children with Developmental Language Disorder (DLD) from Children with Typical Language Development

Computer based analyses offer a possibility for objective methods to assess semantic-linguistic quality of narratives at the text level. The aim of the present study is to investigate whether a semantic language impairment index (SELIMI) based on latent semantic analysis (LSA) can discriminate between children with developmental language disorder (DLD) and children with typical language development. Spoken narratives from 54 children with DLD and 54 age matched controls with typical language development were summarized in a semantic representation generated using LSA. A statistical model was trained to discriminate between children with DLD and children with typical language development, given the semantic vector representing each individual child's narrative. The results show that SELIMI could distinguish between children with DLD and children with typical language development significantly better than chance and thus has a potential to complement traditional analyses focussed on form or on the word level.

Early Literacy Predictors and Second-Grade Outcomes in Children Who Are Hard of Hearing

This study contrasted the early literacy outcomes of children who are hard of hearing (CHH) with children with normal hearing (CNH). At age 5, prereading skills of oral language, phonological processing, and print knowledge were examined in CHH (N = 180) and CNH (N = 80). The CHH had poorer oral language and phonological processing abilities than the CNH but comparable knowledge of print. At age 8, measures of word reading, and reading comprehension yielded no differences between CHH (N = 108) and CNH (N = 62) except for reading comprehension for the moderately severe CHH. Reading achievement in CHH was found to exceed predictions based on prereading performance. This resilience was associated with gains in oral language during the early school years.

Selección de pruebas del lenguaje y análisis crítico de su aplicación en población infantil con discapacidad auditiva

El objetivo de este estudio ha consistido en seleccionar aquellas pruebas que mejor permitieran estudiar desde un punto de vista formal, el lenguaje del niño/a con hipoacusia. Aunque no hay un consenso general, consideramos que es fundamental analizar todos los aspectos del lenguaje, para tener un conocimiento más completo del desarrollo lingüístico, porque no es paralelo en todos sus ámbitos. Las pruebas escogidas han sido: el test PEABODY; el registro fonológico de Laura Bosch; EDAF; EMLE-TALE 2000; PLON-R y BLOC-SR. Esta evaluación se complementa con un cuestionario dirigido a quienes aplican los test y con la opinión de expertos logopedas en el terreno práctico. En términos generales todas las pruebas han resultado adecuadas en función de su finalidad. Las que mejor se corrigen son EDAF, PEABODY y BLOC-SR y la que peor, el registro fonológico de Laura Bosch. Para nosotros, el procedimiento de aplicación de PEABODY y PLON-R es ideal para niños con hipoacusia, presentando mayores dificultades el EDAF y BLOC-SR y siendo muy difíciles de aplicar, el registro fonológico de Laura Bosch y el EMLE. Consideramos que la selección realizada para evaluar el desarrollo del lenguaje en el niño/a con discapacidad auditiva es adecuada, siempre y cuando tengamos en cuenta la edad de desarrollo y las modificaciones específicas que debemos adoptar en esta población.

The Effect of Hearing Loss on Novel Word Learning in Infant- and Adult-Directed Speech

OBJECTIVES

Relatively little is known about how young children with hearing impairment (HI) learn novel words in infant- and adult-directed speech (ADS). Infant-directed speech (IDS) supports word learning in typically developing infants relative to ADS. This study examined how children with normal hearing (NH) and children with HI learn novel words in IDS and ADS. It was predicted that IDS would support novel word learning in both groups of children. In addition, children with HI were expected to be less proficient word learners as compared with their NH peers.

DESIGN

A looking-while-listening paradigm was used to measure novel word learning in 16 children with sensorineural HI (age range 23.2 to 42.1 months) who wore either bilateral hearing aids (n = 10) or bilateral cochlear implants (n = 6) and 16 children with NH (age range 23.1 to 42.1 months) who were matched for gender, chronological age, and maternal education level. Two measures of word learning were assessed (accuracy and reaction time). Each child participated in two experiments approximately 1 week apart, one in IDS and one in ADS.

RESULTS

Both groups successfully learned the novel words in both speech type conditions, as evidenced by children looking at the correct picture significantly above chance. As a group, children with NH outperformed children with HI in the novel word learning task; however, there were no significant differences between performance on IDS versus ADS. More fine-grained time course analyses revealed that children with HI, and particularly children who use hearing aids, had more difficulty learning novel words in ADS, compared with children with NH.

CONCLUSIONS

The pattern of results observed in the children with HI suggests that they may need extended support from clinicians and caregivers, through the use of IDS, during novel word learning. Future research should continue to focus on understanding the factors (e.g., device type and use, age of intervention, audibility, acoustic characteristics of input, etc.) that may influence word learning in children with HI in both IDS and ADS.

Detecting and Learning New Words: The Impact of Advancing Age and Hearing Loss

PURPOSE

Lexical acquisition was examined in children and adults to determine if the skills needed to detect and learn new words are retained in the adult years. In addition to advancing age, the effects of hearing loss were also examined.

METHOD

Measures of word recognition, detection of nonsense words within sentences, and novel word learning were obtained in quiet for 20 children with normal hearing and 21 with hearing loss (8-12 years) as well as for 15 adults with normal hearing and 17 with hearing loss (58-79 years). Listeners with hearing loss were tested with and without high-frequency acoustic energy to identify the type of amplification (narrowband, wideband, or frequency lowering) that yielded optimal performance.

RESULTS

No differences were observed between the adults and children with normal hearing except for the adults' better nonsense word detection. The poorest performance was observed for the listeners with hearing loss in the unaided condition. Performance improved significantly with amplification to levels at or near that of their counterparts with normal hearing. With amplification, the adults performed as well as the children on all tasks except for word recognition.

CONCLUSIONS

Adults retain the skills necessary for lexical acquisition regardless of hearing status. However, uncorrected hearing loss nearly eliminates these skills.

Deficits in comprehending wh-questions in children with hearing loss - the contribution of phonological short-term memory and syntactic complexity

The aim of the study is to investigate if German children with hearing loss (HL) display persisting problems in comprehending complex sentences and to find out whether these problems can be linked to limitations in phonological short-term memory (PSTM). A who-question comprehension test (picture pointing) and a nonword repetition (NWR) task were conducted with 21 German children with bilateral sensorineural HL (ages 3-4) and with age-matched 19 normal hearing (NH) children. Follow-up data (ages 6-8) are reported for 10 of the children with HL. The data reveal that the comprehension of who-questions as well as PSTM was significantly more impaired in children with HL than in children with NH. For both groups of participants, there were no correlations between question comprehension scores and performance in the NWR test. Syntactic complexity (subject vs. object question) affected question comprehension in children with HL, however, these problems were overcome at school age. In conclusion, the data indicate that a hearing loss affects the comprehension of complex sentences. The observed problems did, however, not persist and were, therefore, unlikely to be caused by a genuine syntactic deficit. For the tested wh-questions, there is no indication that syntactic comprehension problems of children with HL are due to limitations in PSTM.

Language Development and Impairment in Children With Mild to Moderate Sensorineural Hearing Loss

PURPOSE

The goal of this study was to examine language development and factors related to language impairments in children with mild to moderate sensorineural hearing loss (MMHL).

METHOD

Ninety children, aged 8-16 years (46 children with MMHL; 44 aged-matched controls), were administered a battery of standardized language assessments, including measures of phonological processing, receptive and expressive vocabulary and grammar, word and nonword reading, and parental report of communication skills. Group differences were examined after controlling for nonverbal ability.

RESULTS

Children with MMHL performed as well as controls on receptive vocabulary and word and nonword reading. They also performed within normal limits, albeit significantly worse than controls, on expressive vocabulary, and on receptive and expressive grammar, and worse than both controls and standardized norms on phonological processing and parental report of communication skills. However, there was considerable variation in performance, with 26% showing evidence of clinically significant oral or written language impairments. Poor performance was not linked to severity of hearing loss nor age of diagnosis. Rather, outcomes were related to nonverbal ability, maternal education, and presence/absence of family history of language problems.

CONCLUSIONS

Clinically significant language impairments are not an inevitable consequence of MMHL. Risk factors appear to include lower maternal education and family history of language problems, whereas nonverbal ability may constitute a protective factor.

Acquisition of who-question comprehension in German children with hearing loss

For children with sensorineural hearing loss the ability to understand wh-questions might be particularly challenging because they often have only restricted access to spoken language input during optimal periods of language acquisition. In previous research it has been suggested that this restricted input during critical stages in language acquisition might lead to syntactic deficits that persist into adolescence. In this study we want to pursue this issue by investigating the comprehension of wh-questions in German children with bilateral sensorineural hearing loss. We report results of a who-question comprehension task in a group of 21 3- to 4-year-old German hard-of-hearing children compared to a group of age-matched children with normal hearing. The group data and individual performance patterns suggest that the syntactic comprehension difficulties observed in some, but not all, of the children with hearing loss reflect a delay in the acquisition of who-question comprehension rather than a persistent syntactic deficit. Follow-up data elicited from a subgroup of children confirm this supposition.

Benefits of augmentative signs in word learning: Evidence from children who are deaf/hard of hearing and children with specific language impairment

BACKGROUND

Augmentative signs may facilitate word learning in children with vocabulary difficulties, for example, children who are Deaf/Hard of Hearing (DHH) and children with Specific Language Impairment (SLI). Despite the fact that augmentative signs may aid second language learning in populations with a typical language development, empirical evidence in favor of this claim is lacking.

AIMS

We aim to investigate whether augmentative signs facilitate word learning for DHH children, children with SLI, and typically developing (TD) children.

METHODS AND PROCEDURES

Whereas previous studies taught children new labels for familiar objects, the present study taught new labels for new objects. In our word learning experiment children were presented with pictures of imaginary creatures and pseudo words. Half of the words were accompanied by an augmentative pseudo sign. The children were tested for their receptive word knowledge.

OUTCOMES AND RESULTS

The DHH children benefitted significantly from augmentative signs, but the children with SLI and TD age-matched peers did not score significantly different on words from either the sign or no-sign condition.

CONCLUSIONS AND IMPLICATIONS

These results suggest that using Sign-Supported speech in classrooms of bimodal bilingual DHH children may support their spoken language development. The difference between earlier research findings and the present results may be caused by a difference in methodology.

Working memory and referential communication-multimodal aspects of interaction between children with sensorineural hearing impairment and normal hearing peers

Whereas the language development of children with sensorineural hearing impairment (SNHI) has repeatedly been shown to differ from that of peers with normal hearing (NH), few studies have used an experimental approach to investigate the consequences on everyday communicative interaction. This mini review gives an overview of a range of studies on children with SNHI and NH exploring intra- and inter-individual cognitive and linguistic systems during communication. Over the last decade, our research group has studied the conversational strategies of Swedish speaking children and adolescents with SNHI and NH using referential communication, an experimental analog to problem-solving in the classroom. We have established verbal and non-verbal control and validation mechanisms, related to working memory capacity and phonological short term memory. We present main findings and future directions relevant for the field of cognitive hearing science and for the clinical and school-based management of children and adolescents with SNHI.

Lexical access in children with hearing loss or specific language impairment, using the cross-modal picture-word interference paradigm

In this study we compared lexical access to spoken words in 25 deaf children with cochlear implants (CIs), 13 hard-of-hearing (HoH) children and 20 children with specific language impairment (SLI). Twenty-one age-matched typically developing children served as controls. The children with CIs and the HoH children in the present study had good speech perception abilities. We used a cross-modal picture-word interference paradigm to examine lexical access. Results showed that children with SLI revealed overall slower reaction times and produced more errors than the children with CIs, the HoH children, and the control children. Reaction times of children with CIs and the HoH children did not differ from those of the control children. Thus, problems with spoken language processing, as is the case in children with SLI, seem to affect lexical access more than limitations in auditory perception, as is the fundamental problem in children with hearing loss. We recommend that improvement of lexical access in children with SLI deserves specific attention in therapy and education.

Does the speaker's voice quality influence children's performance on a language comprehension test?

PURPOSE

A small number of studies have explored children's perception of speakers' voice quality and its possible influence on language comprehension. The aim of this explorative study was to investigate the relationship between the examiner's voice quality, the child's performance on a digital version of a language comprehension test, the Test for Reception of Grammar (TROG-2), and two measures of cognitive functioning.

METHOD

The participants were (n = 86) mainstreamed 8-year old children with typical language development. Two groups of children (n = 41/45) were presented with the TROG-2 through recordings of one female speaker: one group was presented with a typical voice and the other with a simulated dysphonic voice.

RESULT

Significant associations were found between executive functioning and language comprehension. The results also showed that children listening to the dysphonic voice achieved significantly lower scores for more difficult sentences ("the man but not the horse jumps") and used more self-corrections on simpler sentences ("the girl is sitting").

CONCLUSION

Findings suggest that a dysphonic speaker's voice may force the child to allocate capacity to the processing of the voice signal at the expense of comprehension. The findings have implications for clinical and research settings where standardized language tests are used.

Differences in phonologic and prosodic abilities in children with phonological language impairment and phonological-grammatical language impairment assessed with non-word repetition

Prosody can be described as the rhythmic, dynamic, and melodic aspects of language. Swedish has a relatively complex prosodic system compared to, for example, English. A large percentage of Swedish children with language impairment show prosodic problems to some extent. In the present study, non-word repetition was used to assess the phonological and prosodic abilities in children with phonological language impairment and children with phonological-grammatical language impairment. In the study, 10 children with phonological language impairment and 14 children with phonological-grammatical language impairment from 4;3 to 6;2 years of age participated. All children heard the same recorded non-words and words. The group with phonological language impairment received higher scores in all variables, compared to the group with phonological-grammatical language impairment. The results showed significant differences between the groups regarding production of vowels correct in words and production of phonemes correct in non-words as well as production of unstressed syllables in non-words and production of correct stress in non-words. Percent correctly produced vowels in words, but not in non-words, correlated significantly with grammatical ability.

Cortical electrophysiological markers of language abilities in children with hearing AIDS: a pilot study

Objective. To investigate cortical auditory evoked potentials (CAEPs) in pediatric hearing aid (HA) users, with and without language impairment. Design. CAEPs were measured in 11 pediatric HA users (age: 8–12 years) with moderate bilateral sensorineural hearing loss (HL); participants were classified according to language ability. CAEPs were also measured for a control group of 11 age-matched, normal-hearing (NH) children. Results. HL children without language impairment exhibited normal CAEPs. HL children with language impairment exhibited atypical temporal CAEPs, characterized by the absence of N1c; frontocentral responses displayed normal age-related patterns. Conclusion. Results suggest that abnormal temporal brain function may underlie language impairment in pediatric HA users with moderate sensorineural HL.

Performance of children on the Turkish Nonword Repetition Test: Effect of word similarity, word length, and scoring

This study aims to report the preliminary results of the development of the Turkish Nonword Repetition Test and to contribute to the clinical accuracy of the test by comparing the performance of children with specific language impairment with that of language-level matched and age-matched typically developing children on a nonword repetition (NWR) test developed for Turkish. To determine the effect of word similarity and word length, the Turkish Nonword Repetition Test is composed of language-like and language-unlike items. To determine the effect of scoring, the performances of children were scored as correct/incorrect for a whole word, for only the consonants, and for only the vowels. The findings suggest that the test is a reliable tool to differentiate Turkish-speaking children with SLI from typically developing children.

The strengths and weaknesses in verbal short-term memory and visual working memory in children with hearing impairment and additional language learning difficulties

OBJECTIVES

To compare verbal short-term memory and visual working memory abilities of six children with congenital hearing-impairment identified as having significant language learning difficulties with normative data from typically hearing children using standardized memory assessments.

METHODS

Six children with hearing loss aged 8-15 years were assessed on measures of verbal short-term memory (Non-word and word recall) and visual working memory annually over a two year period. All children had cognitive abilities within normal limits and used spoken language as the primary mode of communication. The language assessment scores at the beginning of the study revealed that all six participants exhibited delays of two years or more on standardized assessments of receptive and expressive vocabulary and spoken language.

RESULTS

The children with hearing-impairment scores were significantly higher on the non-word recall task than the "real" word recall task. They also exhibited significantly higher scores on visual working memory than those of the age-matched sample from the standardized memory assessment.

CONCLUSIONS

Each of the six participants in this study displayed the same pattern of strengths and weaknesses in verbal short-term memory and visual working memory despite their very different chronological ages. The children's poor ability to recall single syllable words in relation to non-words is a clinical indicator of their difficulties in verbal short-term memory. However, the children with hearing-impairment do not display generalized processing difficulties and indeed demonstrate strengths in visual working memory. The poor ability to recall words, in combination with difficulties with early word learning may be indicators of children with hearing-impairment who will struggle to develop spoken language equal to that of their normally hearing peers. This early identification has the potential to allow for target specific intervention that may remediate their difficulties.

Coordination of gaze and speech in communication between children with hearing impairment and normal-hearing peers

PURPOSE

To investigate gaze behavior during communication between children with hearing impairment (HI) and normal-hearing (NH) peers.

METHOD

Ten HI-NH and 10 NH-NH dyads performed a referential communication task requiring description of faces. During task performance, eye movements and speech were tracked. Using verbal event (questions, statements, back channeling, and silence) as the predictor variable, group characteristics in gaze behavior were expressed with Kaplan-Meier survival functions (estimating time to gaze-to-partner) and odds ratios (comparing number of verbal events with and without gaze-to-partner). Analyses compared the listeners in each dyad (HI: n = 10, mean age = 12;6 years, mean better ear pure-tone average = 33.0 dB HL; NH: n = 10, mean age = 13;7 years).

RESULTS

Log-rank tests revealed significant group differences in survival distributions for all verbal events, reflecting a higher probability of gaze to the partner's face for participants with HI. Expressed as odds ratios (OR), participants with HI displayed greater odds for gaze-to-partner (ORs ranging between 1.2 and 2.1) during all verbal events.

CONCLUSIONS

The results show an increased probability for listeners with HI to gaze at the speaker's face in association with verbal events. Several explanations for the finding are possible, and implications for further research are discussed.

The slower the better? Does the speaker's speech rate influence children's performance on a language comprehension test?

The aim of this study was to examine the effects of speech rate on children's performance on a widely used language comprehension test, the Test for Reception of Grammar, version 2 (TROG'2), and to explore how test performance interacts with task difficulty and with the child's working memory capacity. Participants were 102 typically-developing Swedish-speaking children randomly assigned to one of the three conditions; the TROG'2 sentences spoken by a speech-language pathologist with slow, normal or fast speech rate. Results showed that the fast speech rate had a negative effect on the TROG'2 scores and that slow rate was more beneficial in general. However, for more difficult tasks the beneficial effect of slow speech was only pronounced for children with better scores on a working memory task. The interpretation is that slow speech is particularly helpful when children do not yet fully master a task but are just about to grasp it. These results emphasize the necessity of careful considerations of the role dynamic aspects of examiner's speech might play in test administration and favour digitalized procedures in standardized language comprehension assessment.

Nonword repetition--a clinical marker for specific language impairment in Swedish associated with parents' language-related problems

First, we explore the performance of nonword repetition (NWR) in children with specific language impairment (SLI) and typically developing children (TD) in order to investigate the accuracy of NWR as a clinical marker for SLI in Swedish-speaking school-age children. Second, we examine the relationship between NWR, family aggregation, and parental level of education in children with SLI. A sample of 61 children with SLI, and 86 children with TD, aged 8-12 years, were administered an NWR test. Family aggregation, measured as the prevalence of language and/or literacy problems (LLP) in parents of the children with SLI, was based on family history interviews. The sensitivity and specificity of nonword repetition was analyzed in a binary logistic regression, cut-off values were established with ROC curves, and positive and negative likelihood ratios reported. Results from the present study show that NWR distinguishes well between Swedish-speaking school-children with and without SLI. We found 90.2% sensitivity and 97.7% specificity at a cut-off level of -2 standard deviations for binary scoring of nonwords. Differences between the SLI and TD groups showed large effect sizes for the two scoring measures binary (d = 2.11) and percent correct consonants (PCC) (d = 1.79). The children with SLI were split into two subgroups: those with no parents affected with LLP (n = 12), and those with one or both parents affected (n = 49). The subgroup consisting of affected parents had a significantly lower score on NWR binary (p = .037), and there was a great difference between the subgroups (d = 0.7). When compared to the TD group, the difference from the subgroup with affected parents was almost one standard deviation larger (d = 2.47) than the difference from the TD to the subgroup consisting of non-affected parents (d = 1.57). Our study calls for further exploration of the complex interaction between family aggregation, language input, and phenotypes of SLI.

The effects of audibility and novel word learning ability on vocabulary level in children with cochlear implants

OBJECTIVES

A novel word learning (NWL) paradigm was used to explore underlying phonological and cognitive mechanisms responsible for delayed vocabulary level in children with cochlear implants (CIs).

METHODS

One hundred and one children using CIs, 6-12 years old, were tested along with 47 children with normal hearing (NH). Tests of NWL, receptive vocabulary, and speech perception at 2 loudness levels were administered to children with CIs. Those with NH completed the NWL task and a receptive vocabulary test. CI participants with good audibility (GA) versus poor audibility (PA) were compared on all measures. Analysis of variance was used to compare performance across the children with NH and the two groups of children with CIs. Multiple regression analysis was employed to identify independent predictors of vocabulary outcomes.

RESULTS

Children with CIs in the GA group scored higher in receptive vocabulary and NWL than children in the PA group, although they did not reach NH levels. CI-aided pure tone threshold and performance on the NWL task predicted independent variance in vocabulary after accounting for other known predictors.

DISCUSSION

Acquiring spoken vocabulary is facilitated by GA with a CI and phonological learning and memory skills. Children with CIs did not learn novel words at the same rate or achieve the same receptive vocabulary levels as their NH peers. Maximizing audibility for the perception of speech and direct instruction of new vocabulary may be necessary for children with CIs to reach levels seen in peers with NH.

Profiles of verbal working memory growth predict speech and language development in children with cochlear implants

PURPOSE

Verbal short-term memory (STM) and working memory (WM) skills predict speech and language outcomes in children with cochlear implants (CIs) even after conventional demographic, device, and medical factors are taken into account. However, prior research has focused on single end point outcomes as opposed to the longitudinal process of development of verbal STM/WM and speech-language skills. In this study, the authors investigated relations between profiles of verbal STM/WM development and speech-language development over time.

METHOD

Profiles of verbal STM/WM development were identified through the use of group-based trajectory analysis of repeated digit span measures over at least a 2-year time period in a sample of 66 children (ages 6-16 years) with CIs. Subjects also completed repeated assessments of speech and language skills during the same time period.

RESULTS

Clusters representing different patterns of development of verbal STM (digit span forward scores) were related to the growth rate of vocabulary and language comprehension skills over time. Clusters representing different patterns of development of verbal WM (digit span backward scores) were related to the growth rate of vocabulary and spoken word recognition skills over time.

CONCLUSION

Different patterns of development of verbal STM/WM capacity predict the dynamic process of development of speech and language skills in this clinical population.

The effect of bilingual exposure versus language impairment on nonword repetition and sentence imitation scores

PURPOSE

Nonword repetition (NWR) and sentence imitation (SI) are increasingly used as diagnostic tools for the identification of Primary Language Impairment (PLI). They may be particularly promising diagnostic tools for bilingual children if performance on them is not highly affected by bilingual exposure. Two studies were conducted which examined (1) the effect of amount of bilingual exposure on performance on French and English nonword repetition and sentence imitation in 5-year-old French-English bilingual children and (2) the diagnostic accuracy of the French versions of these measures and of receptive vocabulary in 5-year-old monolingual French-speakers and bilingual speakers with and without PLI, carefully matched on language exposure.

METHOD

Study 1 included 84 5-year-olds acquiring French and English simultaneously, differing in their amount of exposure to the two languages but equated on age, nonverbal cognition and socio-economic status. Children were administered French and English tests of NWR and SI. In Study 2, monolingual and bilingual children with and without PLI (four groups, n=14 per group) were assessed for NWR, SI, and receptive vocabulary in French to determine diagnostic accuracy.

RESULTS

Study 1: Both processing measures, but in particular NWR, were less affected by previous exposure than vocabulary measures. Bilingual children with varying levels of exposure were unaffected by the length of nonwords. Study 2: In contrast to receptive vocabulary, NWR and SI correctly distinguished children with PLI from children with typical development (TD) regardless of bilingualism. Sensitivity levels were acceptable, but specificity was lower.

CONCLUSIONS

Bilingual children perform differently than children with PLI on NWR and SI. In contrast to children with PLI, bilingual children with a large range of previous exposure levels achieve high NWR scores and are unaffected by the length of the nonwords.

LEARNING OUTCOMES

Readers will recognize the effect of language input on the rate of language development, focusing specifically on how bilingual exposure affects the language learning of each language of bilingual children.

Non-word repetition in adolescents with specific language impairment (SLI)

BACKGROUND

Non-word repetition (NWR) difficulties are common, but not universal, among children with specific language impairment (SLI). However, older children and adolescents with SLI have rarely been studied. Studies disagree on the relationship between NWR difficulties and difficulties with other areas of language and literacy. There is also no consensus about the underlying reason for the difficulties (some) children with SLI have with NWR. Some scholars argue that difficulties with phonological short-term memory or storage cause NWR and other language difficulties, whereas others argue that difficulties with NWR may be due more to difficulties with phonological representations.

AIMS

To investigate NWR abilities and their relationship to other language and literacy abilities in a group of older children with SLI and typically developing controls. To investigate the relative effects of increasing phonological complexity and the number of syllables on the ability of the participants to repeat non-words.

METHODS & PROCEDURES

An NWR test (The Test of Phonological Structure; TOPhS), which systematically varies phonological complexity, was administered to 15 participants with SLI (aged 11-15 years), 30 language and 15 age controls. Standardized language and literacy tests and a specific test of verb agreement and tense marking (Verb Agreement and Tense Test; VATT) were also administered.

OUTCOMES & RESULTS

The participants with SLI showed a bimodal distribution: half achieved age-appropriate NWR, while half scored significantly below language and age controls (d > 7). The two groups of participants with SLI (high versus low scorers) only differed in NWR (d > 5) and agreement (d > 3) and tense marking (d > 2.5), not on the standardized language and literacy measures administered. NWR was also highly correlated with verb agreement (r= 0.97) and tense marking (r= 0.89) among participants with SLI, but not among controls (r= 0.16 and 0.30 respectively). Phonological complexity was related to NWR accuracy, particularly among participants with SLI. The number of syllables had no independent effect on NWR performance for any group.

CONCLUSIONS & IMPLICATIONS

Some children with SLI (who have good NWR) have language difficulties unrelated to any of the factors underlying NWR. Others have a (probably additional) deficit which affects NWR and also leads to greater difficulties with verb agreement and tense marking. The results indicate that difficulties with this particular NWR test are more likely to be due to a deficit with phonology per se, rather than with phonological short-term memory or storage.

Vocabulary and working memory in children fit with hearing aids

PURPOSE

To determine whether children with mild-to-moderately severe sensorineural hearing loss (CHL) present with disturbances in working memory and whether these disturbances relate to the size of their receptive vocabularies.

METHOD

Children 6 to 9 years of age participated. Aspects of working memory were tapped by articulation rate, forward and backward digit span in the auditory and visual modalities, Corsi span, parent surveys, and a sequential encoding task. Articulation rate, digit spans, and Corsi spans were also administered in low-level broadband noise.

RESULTS

CHL and children with normal hearing (CNH) demonstrated auditory advantage in forward serial recall. CHL demonstrated slower articulation rates than CNH, but similar memory spans. CHL with poor executive function presented with poorer performance on the Corsi span task. The presence of background noise had no effect on performance in either group. CHL presented with significantly smaller receptive vocabularies than their CNH peers. Across groups, receptive vocabulary size was positively correlated with digit span in quiet, Corsi span in noise, and articulation rate.

CONCLUSIONS

In the presence of mild-to-moderately severe hearing loss, children demonstrated resilient working memory systems. For all children, working memory and vocabulary were related; that is, children with poorer working memory had smaller vocabulary sizes.

Narrative skills in Swedish children with language impairment

This study investigated the development of narrative skills in Swedish children with language impairment between age 5 and age 10. Seventeen children with LI and two control groups of age peers with typical development participated in a picture elicited story telling task. Analyses included measures of story content, cohesion and grammar. Our subjects showed development in different areas from age 5 to 10, but they did not perform at the level of the controls at age 10 on number of different verbs used and percent grammatically correct C-units. We conclude that preschool children with LI develop in their narrative skills over time, but not to the level of their age-peers at age 10.

LEARNING OUTCOMES

The reader will be able to describe areas of vulnerability in Swedish-speaking children with language impairment in general, and related to narration in particular. Furthermore, the reader will be able to describe similarities in narrative skills between Swedish-speaking and English-speaking children with language impairment.

Age-related benefits of digital noise reduction for short-term word learning in children with hearing loss

PURPOSE

To determine the rate of word learning for children with hearing loss (HL) in quiet and in noise compared to normal-hearing (NH) peers. The effects of digital noise reduction (DNR) were examined for children with HL.

METHOD

Forty-one children with NH and 26 children with HL were grouped by age (8-9 years and 11-12 years). The children learned novel words associated with novel objects through a process of trial and error. Functions relating performance across trials were calculated for each child in each listening condition and were compared.

RESULTS

Significant effects were observed for age (older > younger) in the children with NH and listening condition (quiet > noise) in the children with HL. Significant effects of hearing status were also observed across groups (NH > HL), indicating that the children with HL required more trials to learn the new words. However, word learning improved significantly in noise with the use of DNR for the older but not for the younger children with HL. Hearing aid history and signal-to-noise ratio did not contribute to performance.

CONCLUSION

Word learning was significantly reduced in younger children, in noise, and in the presence of hearing loss. Age-related benefits of DNR were apparent for children over 10 years of age.

Sensitivity and specificity of French language and processing measures for the identification of primary language impairment at age 5

PURPOSE

Research on the diagnostic accuracy of different language measures has focused primarily on English. This study examined the sensitivity and specificity of a range of measures of language knowledge and language processing for the identification of primary language impairment (PLI) in French-speaking children. Because of the lack of well-documented language measures in French, it is difficult to accurately identify affected children, and thus research in this area is impeded.

METHOD

The performance of 14 monolingual French-speaking children with confirmed, clinically identified PLI (M = 61.4 months of age, SD = 7.2 months) on a range of language and language processing measures was compared with the performance of 78 children with confirmed typical language development (M age = 58.9 months, SD = 5.7). These included evaluations of receptive vocabulary, receptive grammar, spontaneous language, narrative production, nonword repetition, sentence imitation, following directions, rapid automatized naming, and digit span. Sensitivity, specificity, and likelihood ratios were determined at 3 cutoff points: (a) -1 SD, (b) -1.28 SD, and (b) -2 SD below mean values. Receiver operator characteristic curves were used to identify the most accurate cutoff for each measure.

RESULTS

Significant differences between the PLI and typical language development groups were found for the majority of the language measures, with moderate to large effect sizes. The measures differed in their sensitivity and specificity, as well as in which cutoff point provided the most accurate decision. Ideal cutoff points were in most cases between the mean and -1 SD. Sentence imitation and following directions appeared to be the most accurate measures.

CONCLUSIONS

This study provides evidence that standardized measures of language and language processing provide accurate identification of PLI in French. The results are strikingly similar to previous results for English, suggesting that in spite of structural differences between the languages, PLI in both languages involves a generalized language delay across linguistic domains, which can be identified in a similar way using existing standardized measures.

The relationship between phonological memory, phonological sensitivity, and incidental word learning

This study investigated the cognitive abilities needed to succeed at incidental word learning, specifically by examining the role of phonological memory and phonological sensitivity in novel word learning by 4-year-olds who were typically developing. Forty 4-year-olds were administered a test of nonword repetition (to investigate phonological memory), rhyming and phoneme alliteration tasks (to investigate phonological sensitivity), and an incidental word learning task (via a computer-based presentation of a cartoon story). A multiple regression analysis revealed that nonword repetition scores did not contribute significantly to incidental word learning. Phonological sensitivity scores were significant predictors of incidental word learning. These findings provide support for a model of lexical acquisition in which phonological knowledge plays an important role.

Word learning in children with primary language impairment: a meta-analysis

PURPOSE

The present study is a meta-analysis that examines the difference in novel word learning performance between children with primary language impairment (LI) and typically developing children. Participant and task characteristics were examined as variables that potentially moderated children's word learning.

METHOD

Eight hundred and forty-six published studies were retrieved from conventional databases (PsycINFO, MEDLINE, and Web of Science). Of these studies, 28 met the criteria for inclusion in the meta-analysis, yielding 244 effect sizes across experimental conditions.

RESULTS

LI groups showed significantly lower word learning performance than typical age-matched groups and equivalent performance to typical language-matched groups. Moderator analyses showed that the magnitude of the group difference relative to age peers was significantly associated with participants' chronological age, receptive language and cognitive abilities, task and novel word type, and the extent of novel word exposure.

CONCLUSION

The difference in novel word learning performance between children with LI and age-matched children is strongly affected by task and participant characteristics in the primary studies.

Is age at implant the only factor that counts? The influence of working memory on lexical and grammatical development in children with cochlear implants

In this study, we explored the influence of time factors (age at implant, time with cochlear implant and age), complex working memory and phonological short-term memory on lexical and grammatical development in congenitally deaf children with cochlear implants. Fifteen children (aged 5 years 4 months to 11 years 5 months) were examined with the use of several linguistic and cognitive measures after a minimum of 18 months of implant use. Phonological short-term memory was assessed with non-word repetition, where the percentage of correctly repeated consonants and vowels was counted. For the assessment of lexical acquisition. a novel word learning task was administered. Receptive and expressive grammar was tested. Our results corroborate earlier findings on the influence of phonological short-term memory on novel word learning. The percentage of vowels correctly produced in non-word repetition was more important in this group than age at implant, not only for novel word learning. but also for receptive and expressive grammar.

Factors that influence vocabulary development in two-year-old children

BACKGROUND

This research explored the relative impact of demographic, cognitive, behavioural, and psycholinguistic factors on vocabulary development in two-year-old children.

METHODS

Two hundred and thirty-two children (24-30 months) were tested on expressive and receptive vocabulary, cognitive development, word learning and working memory skills. Parents completed a British adaptation (Klee & Harrison, 2001) of the MacArthur-Bates Communicative Development Inventory (CDI; Fenson et al., 1993), a demographic questionnaire and a questionnaire regarding the child's social-emotional behaviour.

RESULTS

Several demographic, child and processing variables were significantly correlated with CDI (vocabulary) scores, but the only significant unique predictors of CDI scores were nonword repetition (NWR; R(2) change = .36), sex (R(2) change = .05) and age (R(2) change = .04). Scores were only included when a child completed the entire NWR test (77% of toddlers).

CONCLUSIONS

The NWR task used in this experiment maximised participation in this group of toddlers, and was a strong predictor of vocabulary ability. Longitudinal research is warranted to explore the independent and reciprocal growth in working memory and language skills in children.

Striatal degeneration impairs language learning: evidence from Huntington's disease

Although the role of the striatum in language processing is still largely unclear, a number of recent proposals have outlined its specific contribution. Different studies report evidence converging to a picture where the striatum may be involved in those aspects of rule-application requiring non-automatized behaviour. This is the main characteristic of the earliest phases of language acquisition that require the online detection of distant dependencies and the creation of syntactic categories by means of rule learning. Learning of sequences and categorization processes in non-language domains has been known to require striatal recruitment. Thus, we hypothesized that the striatum should play a prominent role in the extraction of rules in learning a language. We studied 13 pre-symptomatic gene-carriers and 22 early stage patients of Huntington's disease (pre-HD), both characterized by a progressive degeneration of the striatum and 21 late stage patients Huntington's disease (18 stage II, two stage III and one stage IV) where cortical degeneration accompanies striatal degeneration. When presented with a simplified artificial language where words and rules could be extracted, early stage Huntington's disease patients (stage I) were impaired in the learning test, demonstrating a greater impairment in rule than word learning compared to the 20 age- and education-matched controls. Huntington's disease patients at later stages were impaired both on word and rule learning. While spared in their overall performance, gene-carriers having learned a set of abstract artificial language rules were then impaired in the transfer of those rules to similar artificial language structures. The correlation analyses among several neuropsychological tests assessing executive function showed that rule learning correlated with tests requiring working memory and attentional control, while word learning correlated with a test involving episodic memory. These learning impairments significantly correlated with the bicaudate ratio. The overall results support striatal involvement in rule extraction from speech and suggest that language acquisition requires several aspects of memory and executive functions for word and rule learning.

Short-term word-learning rate in children with normal hearing and children with hearing loss in limited and extended high-frequency bandwidths

PURPOSE

This study examined children's word learning in limited and extended high-frequency bandwidth conditions. These conditions represent typical listening environments for children with hearing loss (HL) and children with normal hearing (NH), respectively.

METHOD

Thirty-six children with NH and 14 children with moderate-to-severe HL served as participants. All of the children were between 8 and 10 years of age and were assigned to either the limited or the extended bandwidth conditions. Five nonsense words were paired with 5 novel pictures. Word learning was assessed in a single session, multitrial, learning paradigm lasting approximately 15 min. Learning rate was defined as the number of exposures necessary to achieve 70% correct performance.

RESULTS

Analysis of variance revealed a significant main effect for bandwidth but not for group. A Bandwidth x Group interaction was also not observed. In this short-term learning paradigm, the children in both groups required 3 times as many exposures to learn each new word in the limited bandwidth condition compared with the extended bandwidth condition.

CONCLUSION

These results suggest that children with HL may benefit from extended high-frequency amplification when learning new words and for other long-term auditory processes.

Language development and mild-to-moderate hearing loss: does language normalize with age?

PURPOSE

The authors' purpose was to explore the nature of the link between hearing loss (HL) and language impairment in adolescents with mild-to-moderate hearing loss (MMHL). Does language performance (generally or in certain areas) normalize at adolescence?

METHOD

The language skills of 19 French-speaking adolescents (ages 11-15) with moderate or mild sensorineural HL were evaluated via a series of tests assessing oral and written language, including an experimental probe, and compared with typically developing adolescents and adolescents with specific language impairment (SLI).

RESULTS

Language disorders were found, notably in the areas of phonology and grammar, in more than half the adolescents with MMHL; affected domains and error patterns were identical to those found in adolescents with SLI. Language scores of the adolescents with MMHL were significantly linked with degree of HL, a correlation not generally found in studies of children with MMHL.

CONCLUSION

Normalization of language performance does not generalize at adolescence in the context of MMHL. The fact that an effect of the severity of HL was found only after childhood might be because linguistic development is basically complete at adolescence. Prior to this time, this effect could be obscured by developmental rhythms that vary from child to child.