Christophe dos Santos

Extended Statistical Learning as an account for slow vocabulary growth

Stokes (2010) compared the lexicons of English-speaking late talkers (LT) with those of their typically developing (TD) peers on neighborhood density (ND) and word frequency (WF) characteristics and suggested that LTs employed learning strategies that differed from those of their TD peers. This research sought to explore the cross-linguistic validity of this conclusion. The lexicons (production, not recognition) of 208 French-speaking two-year-old children were coded for ND and WF. Regression revealed that ND and WF together predicted 62% of the variance in vocabulary size, with ND and WF uniquely accounting for 53% and 9% of that variance respectively. Epiphenomenal findings were ruled out by comparison of simulated data sets with the actual data. A generalized Mann-Whitney test showed that children with small vocabularies had significantly higher ND values and significantly lower WF values than children with large vocabularies. An EXTENDED STATISTICAL LEARNING theory is proposed to account for the findings.

Parent report of early lexical production in bilingual children: a cross-linguistic CDI comparison

ABSTRACT This paper compared the vocabulary size of a group of 250 bilinguals aged 24–36 months acquiring six different language pairs using an analogous tool, and attempted to identify factors that influence vocabulary sizes and ultimately place children at risk for language delay. Each research group used adaptations of the MacArthur-Bates Communicative Development Inventories: Words and Sentences and a specially designed developmental and language background questionnaire to gather information on risk factors for language impairment, demographic and language exposure variables. The results showed a wide range in vocabulary development which could be somewhat attributed to mothers’ education status, parental concerns about language development and amount of exposure to the second language. We looked at those children performing below the 10th and above the 90th percentile to determine what factors were related to their vocabulary size. Features of the entire group of lower performing children were fewer than 50 words and the absence of two-word combinations by 24 months, lower levels of parental education and parental concerns about language development. The implications for identifying bilingual children at risk for language impairment as well as the language enrichment that might be needed for young bilinguals are outlined.

Proposta de um método para escolha de software de automação de bibliotecas

Apresenta um metodo para avaliacao e selecao de softwares de automacao de bibliotecas. Consiste na atribuicao de criterios e calculos estatisticos em uma lista elaborada para a selecao e avaliacao deste tipo de software. Este metodo pretender servir como instrumento de apoio a tomada de decisao no processo de escolha do software mais adequado as necessidades de cada instituicao. Este trabalho foi motivado por uma demanda do Instituto Brasileiro de Informacao em Ciencia e Tecnologia (IBICT) para automatizar a sua biblioteca.

A Nonword Repetition Task to Assess Bilingual Children’s Phonology

ABSTRACT Children with specific language impairment (SLI) are particularly sensitive to phonological complexity in their language. Their performance drops when there are specific phonological structures or when complexity increases. A nonword repetition (NWR) test, which aims to assess the phonology of bilingual speakers with and without SLI, should include phonological properties that are independent of the language and phonological properties whose complexity is quantifiable. The methodology and constraints related to the creation of a NWR test named LITMUS-NWR-FRENCH, which combines these two objectives, are presented. This task was tested on a population of 67 children, 5½ to 8½ years old, bilingual and monolingual, with and without SLI, having in common French as L1 or L2. Results show that the LITMUS-NWR-FRENCH task differentiates between children with and without SLI in the context of bilingualism. It also shows the influence and importance of phonological complexity in children with SLI.

Identifying language impairment in bilingual children in France and in Germany: Language impairment in bilingual children

BACKGROUND The detection of specific language impairment (SLI) in children growing up bilingually presents particular challenges for clinicians. Non-word repetition (NWR) and sentence repetition (SR) tasks have proven to be the most accurate diagnostic tools for monolingual populations, raising the question of the extent of their usefulness in different bilingual populations. AIMS To determine the diagnostic accuracy of NWR and SR tasks that incorporate phonological/syntactic complexity as discussed in recent linguistic theory. The tasks were developed as part of the Language Impairment Testing in Multilingual Settings (LITMUS) toolkit, in two different national settings, France and Germany, and investigated children with three different home languages: Arabic, Portuguese and Turkish. METHODS & PROCEDURES NWR and SR tasks developed in parallel were administered to 151 bilingual children, aged 5;6-8;11, in France and in Germany, to 64 children in speech-language therapy (SLT) and to 87 children not in SLT, whose first language (L1) was Arabic, Portuguese or Turkish. Children were also administered standardized language tests in each of their languages to determine likely clinical status (typical development (TD) or SLI), and parents responded to a questionnaire including questions about early and current language use (bilingualism factors) and early language development (risk factors for SLI). Monolingual controls included 47 TD children and 29 children with SLI. Results were subjected to inter-group comparisons, to diagnostic accuracy calculation, and to correlation and multiple regression analyses. OUTCOMES & RESULTS In accordance with previous studies, NWR and SR identified SLI in the monolingual children, yielding good to excellent diagnostic accuracy. Diagnostic accuracy in bilingual children was fair to good, generally distinguishing children likely to have SLI from children likely to have TD. Accuracy was necessarily linked to the determination of clinical status, which was based on standardized assessment in each of the childs languages. Positive early development, a composite risk factor for SLI, and not variables related to language exposure and use, generally emerged as the strongest predictor of performance on the two tasks, constituting additional, independent support for the efficacy of NWR and SR in identifying impairment in bilingual children. CONCLUSIONS & IMPLICATIONS NWR and SR tasks informed by linguistic theory are appropriate for use as part of the diagnostic process for identifying language impairment in bilingual children for whom the language of assessment is different from the home language, in diverse sociolinguistic contexts.

Assessing Lebanese bilingual children: The use of Cross-linguistic Lexical Tasks in Lebanese Arabic

ABSTRACT Since norms for vocabulary acquisition in Lebanese bilingual children (L1: Lebanese, L2: French and/or English) do not yet exist, clinical assessment based on normative data and using appropriate tools remains difficult for speech and language therapists. The current study focuses on exploring and comparing lexical performances of typically developing Lebanese bilingual children (32 Bi-TD, aged 5;7 to 6;9) and those with specific language impairment (10 Bi-SLI, aged 5;9 to 7;10), using Cross-Linguistic Lexical Tasks (LITMUS-CLT, COST Action IS0804, 2011) in Lebanese Arabic language (CLT-LB), specific to the Lebanese context. The results confirm that typically developing children have better lexical skills, especially expressive skills, than their peers with specific language impairment. Expressive and receptive performance by both groups of children was found to depend on word class (nouns and verbs). Bi-TD children were more accurate at naming and recognising verbs than the Bi-SLI group. The results of these lexical tasks reveal aspects of the nature of bilingual lexical variation, as well as similarities and differences between the Bi-TD and Bi-SLI groups.

A strategic plan to identify key neurophysiological mechanisms and brain circuits in autism

Autism and Autism Spectrum Disorder (ASD) cover a large variety of clinical profiles which share two main dimensions: social and communication impairment and repetitive behaviors or restricted interests, which are present during childhood. There is now no doubt that genetic factors are a major component in the etiology of autism but precise physiopathological pathways are still being investigated. Furthermore, developmental trajectories combined with compensatory mechanisms will lead to various clinical and neurophysiological profiles which together constitute this Autism Spectrum Disorder. To better understand the pathophysiology of autism, comprehension of key neurophysiological mechanisms and brain circuits underlying the different bioclinical profiles is thus crucial. To achieve this goal we propose a strategy which investigates different levels of information processing from sensory perception to complex cognitive processing, taking into account the complexity of the stimulus and whether it is social or non-social in nature. In order to identify different developmental trajectories and to take into account compensatory mechanisms, we further propose that such protocols should be carried out in individuals from childhood to adulthood representing a wide variety of clinical forms.