Development and validation of a bilingual language battery for language-based learning disabilities.

Doctoral Degree. University of KwaZulu-Natal, Durban.There are social, linguistic, cultural, and political dimensions that impact on health and education in South Africa. The evolving nature of these dimensions demand the use of language assessment tools that are developed and validated for the South African population. Speech-language assessment informs parents and educators of the nature of speech and language difficulties the learner may have and guides the intervention. IsiZulu is the most widely spoken African language in South Africa. Therefore, development of a tool to assess expressive, receptive, and written language skills of learners with language-based learning disorders in isiZulu, is imperative. The aim of this study was to develop and validate a tool for language assessment of isiZulu-English speaking learners in grades 1, 2, and 3 who may have language-based learning disabilities. An assessment tool was designed to assess core language skills and identify early indicators of language-based learning disabilities that may result in academic difficulties. The tool development process aimed to construct an innovative test that is linguistically and culturally sensitive to bilingual or isiZulu-English speakers while the content is rich for identifying indicators of language-based learning disability. Elements in expressive and receptive language, phonological awareness, listening, reading, and mathematically-based language concepts were considered. The conceptual tool development phase involved a systematic literature review, pretesting with two existing tools and consultation of a five member Delphi review panel for advice and reviews. Field trials contributed to the development of test items and procedures and tested the tool’s application in mainstream and remedial schools as well as rural and urban communities of learners in KwaZulu-Natal. A combination of qualitative and quantitative methods were used to collect and analyse data. The results indicated that the new tool was linguistically and culturally appropriate. The majority of the subtests provided good reliability and valid results. The study makes a worthy contribution to the body of knowledge in the field of speech-language therapy and basic education. The results and guidelines from this study set out the basic elements required for development of language assessment tools in other African languages. The development of the assessment tool will yield standardization of a bilingual language assessment tool in South Africa

Linguistic and Cognitive Measures in Arabic-Speaking English Language Learners (ELLs) and monolingual children with and without Developmental Language Disorder (DLD)

Understanding the current level of language knowledge in English Language Learners (ELLs) can present a challenge. The standardized language tests that are commonly used to assess language tap prior knowledge and experience. ELLs may score poorly on such ‘knowledge-based’ measures because of the low levels of exposure to each of their languages. Considerable overlap has been found on several knowledge-based measures (Paradis, 2010) between ELLs and monolingual children with an unexpected delay in language development known as Developmental Language Disorder (DLD). Measures of cognitive processing, on the other hand, are less dependent on ELLs’ linguistic knowledge because they employ nonlinguistic or novel stimuli to tap skills considered to underlie language learning. It has been suggested that processing-dependent tasks such as measures of verbal short-term memory may differentiate ELLs from children with DLD (Kohnert, Windsor, & Yim, 2006; Paradis, Schneider, & Duncan, 2013). This thesis presents three studies that investigated the performance of Arabic-speaking ELLs and monolingual children with and without DLD on linguistic and cognitive measures. Study 1 provided a description of the performance of monolingual Arabic-speaking children on a battery of Arabic language tests. The results of study 1 revealed that the majority of language measures were sensitive to developmental change in younger children between the ages of 6 and 7. Study 2 demonstrated lower standardized scores by ELLs on the Arabic and English knowledge-based language tasks. However, ELLs scored above or at age-level expectations on the cognitive measures, with the exception of an Arabic-nonword repetition task. Study 3 found a significant overlap between ELLs and monolingual Arabic-speaking children with DLD on first language (L1) knowledge-based measures. With the exception of the Arabic nonword repetition task, verbal short-term and working memory tasks distinguished ELLs from children with underlying language impairment. The results indicated that there is a need to develop language assessment measures that evaluate a broad range of language abilities for Arabic-speaking children. The findings also suggested that unlike knowledge-based measures, cognitive measures may be valid assessment tools that minimize the role of linguistic knowledge and experiences and help distinguish between ELLs and children with DLD

Sentence repetition in adolescents with specific language impairments and autism: an investigation of complex syntax

Background: Recent studies have indicated that many children with autism spectrum disorders present with language difficulties that are similar to those of children with specific language impairments, leading some to argue for similar structural deficits in these two disorders. Aims: Repetition of sentences involving long-distance dependencies was used to investigate complex syntax in these groups. Methods & Procedures: Adolescents with specific language impairments (mean age = 15;3, n = 14) and autism spectrum disorders plus language impairment (autism plus language impairment; mean age = 14;8, n = 16) were recruited alongside typically developing adolescents (mean age = 14;4, n = 17). They were required to repeat sentences containing relative clauses that varied in syntactic complexity. Outcomes & Results: The adolescents with specific language impairments presented with greater syntactic difficulties than the adolescents with autism plus language impairment, as manifested by higher error rates on the more complex object relative clauses, and a greater tendency to make syntactic changes during repetition. Conclusions & Implications: Adolescents with specific language impairments may have more severe syntactic difficulties than adolescents with autism plus language impairment, possibly due to their short-term memory limitations

Determination and evaluation of clinically efficient stopping criteria for the multiple auditory steady-state response technique

Background: Although the auditory steady-state response (ASSR) technique utilizes objective statistical detection algorithms to estimate behavioural hearing thresholds, the audiologist still has to decide when to terminate ASSR recordings introducing once more a certain degree of subjectivity. Aims: The present study aimed at establishing clinically efficient stopping criteria for a multiple 80-Hz ASSR system. Methods: In Experiment 1, data of 31 normal hearing subjects were analyzed off-line to propose stopping rules. Consequently, ASSR recordings will be stopped when (1) all 8 responses reach significance and significance can be maintained for 8 consecutive sweeps; (2) the mean noise levels were ≤ 4 nV (if at this “≤ 4-nV” criterion, p-values were between 0.05 and 0.1, measurements were extended only once by 8 sweeps); and (3) a maximum amount of 48 sweeps was attained. In Experiment 2, these stopping criteria were applied on 10 normal hearing and 10 hearing-impaired adults to asses the efficiency. Results: The application of these stopping rules resulted in ASSR threshold values that were comparable to other multiple-ASSR research with normal hearing and hearing-impaired adults. Furthermore, in 80% of the cases, ASSR thresholds could be obtained within a time-frame of 1 hour. Investigating the significant response-amplitudes of the hearing-impaired adults through cumulative curves indicated that probably a higher noise-stop criterion than “≤ 4 nV” can be used. Conclusions: The proposed stopping rules can be used in adults to determine accurate ASSR thresholds within an acceptable time-frame of about 1 hour. However, additional research with infants and adults with varying degrees and configurations of hearing loss is needed to optimize these criteria

Preschool hearing, speech, language, and vision screening

Child health surveillance is part of a broad set of activities, the objective of which is to reduce childhood disability by identifying and managing a multiplicity of conditions at an early stage.1 This includes several screening programmes which are focused on the detection of specific disorders. The value of surveillance and monitoring of child health, growth, and development used to be regarded as self evident. The Hall reports emphasised the importance of applying rigorous criteria for screening programmes in community child health and helped to produce a more coordinated national programme.2–4 However, there is still considerable variation both within and between health authorities in the content, timing, and delivery of child health surveillance. This paper summarises the research evidence presented in a recent issue of the Effective Health Care bulletin, Vol 4, No 2; April, 1998 about hearing, speech and language, and vision screening and is based on recent systematic reviews commissioned by the National Health Service (NHS) Health Technology Assessment Programme. Details of the methods and the results are available in the full reports.5–

Computational Language Assessment in patients with speech, language, and communication impairments

Speech, language, and communication symptoms enable the early detection, diagnosis, treatment planning, and monitoring of neurocognitive disease progression. Nevertheless, traditional manual neurologic assessment, the speech and language evaluation standard, is time-consuming and resource-intensive for clinicians. We argue that Computational Language Assessment (C.L.A.) is an improvement over conventional manual neurological assessment. Using machine learning, natural language processing, and signal processing, C.L.A. provides a neuro-cognitive evaluation of speech, language, and communication in elderly and high-risk individuals for dementia. ii. facilitates the diagnosis, prognosis, and therapy efficacy in at-risk and language-impaired populations; and iii. allows easier extensibility to assess patients from a wide range of languages. Also, C.L.A. employs Artificial Intelligence models to inform theory on the relationship between language symptoms and their neural bases. It significantly advances our ability to optimize the prevention and treatment of elderly individuals with communication disorders, allowing them to age gracefully with social engagement.Comment: 36 pages, 2 figures, to be submite

PREDICTING THE LANGUAGE ABILITIES OF CHILDREN

The ability to learn language is influenced both by children\u27s biological abilities and the environment in which they find themselves. Rather than low test scores alone, it may be that children who exhibit disproportionately low language abilities relative to what would be predicted from their biological abilities and expectations based on their environmental situations may be considered to exhibit a specific language impairment. The present study explores this hypothesis by taking measures aimed at estimating 45 children’s biological potential through direct measures o f parental abilities and environmental situations and examining the ability of these measures to predict children’s language abilities. Predictors were based on parental measures of nonword repetition, nonverbal intelligence, working memory, sentence recall, grammaticality judgment, reading, and family environment. The findings of this study show a myriad of variables affect language development from both biological and environmental factors, implying that learning language involves the interplay between children’s innate makeup and their environmental conditions

Short-term and working memory in children with specific language impairment

Investigations of the cognitive processes underlying Specific Language Impairment (SLI) have implicated deficits in the storage and processing of phonological or verbal information. This thesis reports five studies that investigated the role of short-term and working memory in children with SLI. Study 1 demonstrated SLI deficits on measures of verbal working memory, and short-term memory for verbal but not visuospatial information. Study 2 provided evidence that children with SLI perform at age-level on visuospatial working memory measures. Study 3 demonstrated slower processing in the SLI group across domains, as well as verbal storage decrements, with the greatest deficits found for tasks tapping both of these. Study 4 found SLI deficits on measures of nonword repetition in common use, with greater impairments on the task that relied to a lesser extent on short-term memory. Study 5 established more accurate recall for multisyllabic nonwords than matched single syllable lists for all groups, although the SLI group showed different patterns of phoneme retention. It is suggested that the combination of deficits in generalized processing speed and verbal storage in SLI may be expected to have a drastic and detrimental impact on learning, and provides an account of the disorder that could encompass the range of impairments observed in SLI. The findings also suggest that factors additional to short-term memory contribute to poor nonword repetition in SLI