Contribution à l'étude du développement du langage chez le jeune enfant franco-québécois indemne ou ayant subi un traumatisme cranio-encéphalique

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal

Interactive book-reading to improve inferencing abilities in kindergarten classrooms : a clinical project

Inferencing abilities are crucial to development of reading comprehension. However, few studies addressed those abilities in interventions promoting early literacy skills, especially in kindergartners. The aim of this study was to measure the efficacy of an interactive book-reading intervention targeting inferencing abilities, delivered by a school-based speech-language pathologist (SLP) in whole group kindergarten classes. Two hundred and forty-nine 5-year-old kindergartners from low socio-economic settings were quasi-randomly assigned to either one of the experimental groups (EG1 and EG2) or an active control group (CG). EG1 received a 7-week interactive book-reading intervention followed by a 7-week period where it was up to the teachers to implement aspects of the intervention in their teaching or not. EG2 received the 7-week interactive book-reading intervention only and the active control group received an initial workshop only. Three subtests targeting (1) causal inferences during book-reading, (2) causal inferences in a formal task, and (3) referential inferences in a formal task were performed at pre- and post-intervention assessments. There was a significant Time × Group interaction effect for the first subtest indicating an advantage for EG1 compared to CG over time. EG2 appeared as an intermediary group as its results were not different from EG1 and showing only a trend toward significance (p = 0.064) when compared to CG. There was no significant Time × Group interaction effect for the second subtest. A significant Time × Group interaction effect was present for the third subtest, EG1 and EG2 showing larger improvement than CG

L'accord de l'adjectif chez les enfants francophones avec un trouble spécifique du langage

En dépit du fait que l’étude de la production du syntagme nominal puisse fournir des données riches sur les phénomènes d’accord et de concordance, cette structure demeure peu étudiée. L’étude rapportée ici décrit l’accord intra-nominal, - c’est-à-dire l’accord en genre et en nombre entre les différents éléments qui composent le syntagme nominal (déterminant, nom, adjectif) - chez huit enfants francophones avec un trouble spécifique du langage (TSL) et des enfants témoins appariés selon l’âge, le niveau de langage, ou les capacités mnésiques. Quatre tâches induisent la production de noms de couleurs et de syntagmes avec des adjectifs de grandeur ou de couleur. Malgré l’absence de difficultés apparentes à dénommer les couleurs et les syntagmes avec des adjectifs de grandeur, les enfants TSL présentent plus de difficultés que les témoins à produire les adjectifs variables dans le genre approprié au syntagme nominal. Ces résultats suggèrent des difficultés de vérification de l’accord.Although the study of noun phrase production can provide us with a wealth of information on concord, this structure is quite rarely studied. We present a production study for nominal concord – that is, gender and number agreement between the different elements in a noun phrase (determiner, noun, adjective) - in eight French-speaking children with Specific Language Impairment (SLI) and their age-, language- and memory-matched controls. Fours tasks elicit color words and noun-phrases with color or size adjectives. Despite the fact that children with SLI do not present major difficulties in naming colors or size nouns-phrases, children exhibit more difficulties than controls in producing variable adjectives in gender agreeing with the noun phrase. This suggests that these children have concord verification difficulties.A pesar de que el estudio de la producción del sintagma nominal proporcione datos interesantes sobre la concordancia, esta estructura ha sido muy poco estudiada. Presentamos un experimento sobre la producción de la concordancia intra-nominal – es decir la concordancia entre los elementos del sintagma nominal (determinante, nombre, adjetivo), - en ocho niños francófonos con trastorno específico del lenguaje (TEL) apareados con niños con desarrollo típico, según la edad, el nivel de lenguaje o las capacidades mnémicas. Cuatro actividades elicitan la producción de palabras de color y de sintagmas nominales con adjetivos de tamaño y de color. Los niños con TEL no muestran dificultades evidentes en la denominación de colores ni en los sintagmas nominales de tamaño, pero presentan más dificultades que los niños típicos en la producción de adjetivos variables con el género apropiado al sintagma nominal. Los resultados sugieren que estos niños tienen dificultades en la verificación de la concordancia

Expressive and receptive use of speech and graphic symbols by typically developing children: What skills contribute to performance on structured sentence-level tasks?

Purpose: To explore expressive and receptive use of speech and graphic symbols and relationships with linguistic and cognitive skills in children with typical development. Method: Participants were 82 children with typical development (4 to 9 years). Measures of memory, visual analysis skills, and receptive language were used, along with five experimental tasks with speech or symbols as input (stimulus) or output (response), using single clause and compound clause stimuli. Cluster analysis grouped participants with similar performances patterns, who were then compared on linguistic and cognitive skill measures. Result: The lowest performing group sometimes accurately interpreted graphic symbol utterances that were visible during responding. The mid-performing group was stronger on expressive than receptive symbol utterances when the model did not remain visible. The highest group was comparable on expressive and receptive symbol tasks, but nonetheless stronger with spoken utterances. Relationships of linguistic and cognitive skills with task performance differed across the clusters. Conclusion: The findings help clarify the input-output modality asymmetry in graphic symbol communication. Spoken language proficiency does not directly transfer to sentence-level expressive and receptive graphic symbol use. Exploring potentially challenging sentence-level phenomena is important. Research is warranted to explore developmental progressions and potential clinical applications more systematically

Assessment of Estrogenic Endocrine-Disrupting Chemical Actions in the Brain Using in Vivo Somatic Gene Transfer

Estrogenic endocrine-disrupting chemicals abnormally stimulate vitellogenin gene expression and production in the liver of many male aquatic vertebrates. However, very few studies demonstrate the effects of estrogenic pollutants on brain function. We have used polyethylenimine-mediated in vivo somatic gene transfer to introduce an estrogen response element–thymidine kinase–luciferase (ERE-TK-LUC) construct into the brain. To determine if waterborne estrogenic chemicals modulate gene transcription in the brain, we injected the estrogen-sensitive construct into the brains of Nieuwkoop-Faber stage 54 Xenopus laevis tadpoles. Both ethinylestradiol (EE2; p < 0.002) and bisphenol A (BPA; p < 0.03) increased luciferase activity by 1.9- and 1.5-fold, respectively. In contrast, low physiologic levels of 17β-estradiol had no effect (p > 0.05). The mixed antagonist/agonist tamoxifen was estrogenic in vivo and increased (p < 0.003) luciferase activity in the tadpole brain by 2.3-fold. There have been no previous reports of somatic gene transfer to the fish brain; therefore, it was necessary to optimize injection and transfection conditions for the adult goldfish (Carassius auratus). Following third brain ventricle injection of cytomegalovirus (CMV)-green fluorescent protein or CMV-LUC gene constructs, we established that cells in the telencephalon and optic tectum are transfected. Optimal transfections were achieved with 1 μg DNA complexed with 18 nmol 22 kDa polyethylenimine 4 days after brain injections. Exposure to EE2 increased brain luciferase activity by 2-fold in males (p < 0.05) but not in females. Activation of an ERE-dependent luciferase reporter gene in both tadpole and fish indicates that waterborne estrogens can directly modulate transcription of estrogen-responsive genes in the brain. We provide a method adaptable to aquatic organisms to study the direct regulation of estrogen-responsive genes in vivo

Human mesenchymal stromal cell-secreted lactate induces M2-macrophage differentiation by metabolic reprogramming

Human mesenchymal stromal cells (MSC) have been shown to dampen immune response and promote tissue repair, but the underlying mechanisms are still under investigation. Herein, we demonstrate that umbilical cord-derived MSC (UC-MSC) alter the phenotype and function of monocyte-derived dendritic cells (DC) through lactate-mediated metabolic reprogramming. UC-MSC can secrete large quantities of lactate and, when present during monocyte-to-DC differentiation, induce instead the acquisition of M2-macrophage features in terms of morphology, surface markers, migratory properties and antigen presentation capacity. Microarray expression profiling indicates that UC-MSC modify the expression of metabolic-related genes and induce a M2-macrophage expression signature. Importantly, monocyte-derived DC obtained in presence of UC-MSC, polarize naïve allogeneic CD4+ T-cells into Th2 cells. Treatment of UC-MSC with an inhibitor of lactate dehydrogenase strongly decreases lactate concentration in culture supernatant and abrogates the effect on monocyte-to- DC differentiation. Metabolic analysis further revealed that UC-MSC decrease oxidative phosphorylation in differentiating monocytes while strongly increasing the spare respiratory capacity proportional to the amount of secreted lactate. Because both MSC and monocytes are recruited in vivo at the site of tissue damage and inflammation, we propose the local increase of lactate concentration induced by UC-MSC and the consequent enrichment in M2-macrophage generation as a mechanism to achieve immunomodulation

Prior history of feeding–swallowing difficulties in children with language impairment

Purpose This study updated and extended our previous investigation (Malas et al., 2015) of feeding–swallowing difficulties and concerns (FSCs) in children with language impairments (LI) by using more stringent inclusion criteria and targeting children earlier in the care delivery pathway. Method Retrospective analyses were performed on the clinical files of 29 children (average age: 60 months, SD = 9.0) diagnosed as having LI using standardized testing, nonstandardized testing and final speech-language pathologist judgment. The files of children born prematurely or with a history of anatomical, structural, neurodevelopmental, cognitive, sensory, motor, or speech disorders were excluded. Literature-based indicators were used to determine the prevalence of difficulties in sucking, food transition, food selectivity, and salivary control. Values were compared with the general population estimate of Lindberg et al. (1992). Results A significantly higher percentage of histories of FSCs (48%) were found in the files of children with LI when compared with the population estimate (χ2 = 13.741, df = 1, p < .001). Difficulties in food transition (31%) and food selectivity (14%) were the most frequent. Data confirm and extend our previous findings and suggest that a previous history of FSCs may characterize children with LI early in their care delivery pathway

A multi-site review of policies affecting opportunities for children with developmental disabilities to become bilingual

This review of special education and language-in-education policies at six sites in four countries (Canada, United States, United Kingdom, and Netherlands) aimed to determine the opportunities for bilingualism provided at school for children with developmental disabilities (DD). While research has demonstrated that children with DD are capable of learning more than one language (see Kay Raining Bird, Genesee, & Verhoeven, this issue), it was not clear whether recent policies reflect these findings. The review, conducted using the same protocol across sites, showed that special education policies rarely addressed second language learning explicitly. However, at all sites, the policies favoured inclusion and educational planning based on individual needs, and thus implied that students with DD would have opportunities for second language learning. The language-in-education policies occasionally specified the support individuals with special needs would receive. At some sites, policies and educational options provided little support for minority languages, a factor that could contribute to subtractive bilingualism. At others, we found stronger support for minority languages and optional majority languages: conditions that could be more conducive to additive bilingualism

Nos bouts de choux : linguistes en herbe

Quiconque est témoin du développement du langage d’un enfant ne peut que s’émerveiller devant la facilité avec laquelle, dès l’âge le plus tendre, il parvient à maîtriser sa langue maternelle. Pourtant, cet apprentissage est complexe et exige une grande capacité à exploiter les stimuli de l’environnement pour en dégager des principes qui lui permettront de mettre de l’ordre dans les différents aspects du langage. Cet apprentissage débute dès la grossesse et se poursuivra toute la vie, quoique les années préscolaires soient celles où se produit l’évolution la plus spectaculaire. Outre l’intérêt que l’apprentissage du langage suscite en soi, mieux comprendre comment il s’intègre dans le développement général de l’enfant contribue à projeter une lumière nouvelle sur certaines questions théoriques et cliniques relatives notamment aux concepts de dispositions naturelles perçues comme plus ou moins grandes d’une personne à l’autre

Word-finding behaviours in narration for typically developing French speakers of school age

Background:Research in word-finding difficulties is sparse, especially in lan-guages other than English. As a result, the factors associated with the frequencyof word-finding behaviours are poorly understood, particularly in discourse.Aims:This exploratory study is the first to collect data relative to the expectedfrequency of word-finding behaviours in narration for French speakers aged 7–12 years old with typical development; and (2) to identify the factors associatedwith the frequency of word-finding behaviours in narration. We hypothesizedthat sociodemographic characteristics, language abilities and characteristics ofthe spoken productions could be linked to word-finding behaviours.Methods & Procedures:The participants consisted of 61 French-speakingchildren aged 7–12 years old (M=9;09 years, SD=1;06 years) with typicaldevelopment. Children were asked to complete a receptive vocabulary task,a non-word-repetition task and two narrative tasks. The children’s narrativesamples were coded using a discourse analysis of word-finding behaviours, asdescribed by Diane J. German.Outcomes&Results:Participantsproduced39%ofT-unitswithleastoneword-finding behaviour, which included relatively frequent use of repetitions andword reformulations. Regression analyses revealed that the participants’ genderwas the only significant variable associated with the frequency of word-findingbehaviours in narration. Boys produced a higher percentage of T-units with atleast one word-finding behaviour. Post-hoc analyses suggested that gender dif-ferences reflected differences in repetitions and word reformulations. Boys andgirls did not differ on any other language measures collected.Conclusions & Implications:Speech–language pathologists may want to takeinto account a child’s gender when assessing word-finding difficulties in narra-tion. Additional studies are needed to understand whether this finding extendsto other word-finding tasks and to children with word-finding difficulties