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1.
Clin Linguist Phon ; : 1-14, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39474721

RESUMO

Inferential language is an essential aspect of narrative storytelling. It offers not only details about events such as cause and effect and character cognition (e.g. intentions, actions, and reactions) but other evaluative and descriptive language. Previous studies have shown that children with developmental language disorder (DLD, previously also termed as Specific Language Impairment, SLI) exhibit weakness in narrative development, and such weakness is suggested to be unlikely to be resolved over time. However, studies that have focused on the inferential language use in narratives of adolescents with DLD are almost non-existent, and it is unclear whether inferential language use by adolescents with DLD would remain problematic or achieve close-to-normal performance. To address this issue, we compared the use of inferential language in the oral narratives 19 adolescents with DLD (Mean age = 14.3; SD = 0.64) and 19 adolescents with typical language development (TLD; Mean age = 14.0; SD = 0.50). Each transcribed narrative was coded for inferences across character actions/attempts, internal states, causality, character dialogue and other inferences. Results indicated that the two groups performed similarly in all measures except for assigning possessive expressions. Our results suggest that adolescents with DLD may approximate their typical language development (TLD) peers in terms of the inferential language use in oral narratives.

2.
Dev Sci ; 26(4): e13364, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36546681

RESUMO

Children with developmental language disorder (DLD) regularly use the bare form of verbs (e.g., dance) instead of inflected forms (e.g., danced). We propose an account of this behavior in which processing difficulties of children with DLD disproportionally affect processing novel inflected verbs in their input. Limited experience with inflection in novel contexts leads the inflection to face stronger competition from alternatives. Competition is resolved through a compensatory behavior that involves producing a more accessible alternative: in English, the bare form. We formalize this hypothesis within a probabilistic model that trades off context-dependent versus independent processing. Results show an over-reliance on preceding stem contexts when retrieving the inflection in a model that has difficulty with processing novel inflected forms. We further show that following the introduction of a bias to store and retrieve forms with preceding contexts, generalization in the typically developing (TD) models remains more or less stable, while the same bias in the DLD models exaggerates difficulties with generalization. Together, the results suggest that inconsistent use of inflectional morphemes by children with DLD could stem from inferences they make on the basis of data containing fewer novel inflected forms. Our account extends these findings to suggest that problems with detecting a form in novel contexts combined with a bias to rely on familiar contexts when retrieving a form could explain sequential planning difficulties in children with DLD. RESEARCH HIGHLIGHTS: Generalization difficulties with inflectional morphemes in children with Developmental Language Disorder arise from these children's limited experience with novel inflected forms. Limited experience with a form in novel contexts could lead to a storage bias where retrieving a form often requires relying on familiar preceding stems. While generalization in typically developing models remains stable across a range of model parameters, certain parameter values in the impaired models exaggerate difficulties with generalization. Children with DLD compensate for these retrieval difficulties through accessibility-driven language production: they produce the most accessible form among the alternatives.


Assuntos
Transtornos do Desenvolvimento da Linguagem , Criança , Humanos , Idioma , Testes de Linguagem
3.
Int J Lang Commun Disord ; 58(3): 929-943, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36565246

RESUMO

BACKGROUND: Public awareness of Developmental Language Disorder (DLD) is lower than other neurodevelopmental disorders, despite its high prevalence of 7.6%. This lower awareness means recruitment for DLD research studies is difficult. DLD is both underfunded and under-researched, resulting in relatively limited research investigating individuals with DLD. Engage with Developmental Language Disorder (E-DLD) is a response to these considerations. E-DLD is the first international participant database of those affected by DLD. Parents of children with DLD under 16 and young people and adults over 16 from anywhere in the world can sign up to be a part of the E-DLD. AIMS: This paper aims to describe the families of children with DLD and adults with DLD in the database thus far. METHODS & PROCEDURES: E-DLD members sign up via our website, reporting demographic characteristics as part of this procedure. We request all E-DLD members subsequently fill in a yearly survey. The content of the yearly survey changes dependent on the age of the child, while the yearly survey for adults remains consistent. We measure a wide range of domains, such as speech and language therapy (SLT) support, school support, socialisation skills, and early developmental milestones for our youngest members, and health care support and mental well-being measurements for our adults. We also collect parent and self-reported reflections on strengths and challenges for the person with DLD using open-ended questions and the Strengths and Difficulties Questionnaire. OUTCOMES & RESULTS: The database currently consists of 196 parents of children with DLD and 20 individuals over the age of 16 with DLD or suspected DLD across a range of socioeconomic status (SES) backgrounds. Our initial results confirm that E-DLD members meet the linguistic profile of DLD in relation to self- or parent-rated language difficulties. Both children and adults show increased rates of psychosocial difficulties compared to established norms, consistent with past research on clinical samples of people with DLD. CONCLUSIONS & IMPLICATIONS: The findings indicate that a participant database for DLD research is feasible and useful. The rates of emotional, behavioural and sleep difficulties among the child probands are higher than reported rates amongst typically developing children. Initial data indicate that adults with DLD have poorer well-being than their peers. The E-DLD is a useful collection of data on those affected by DLD and is a promising method for connecting people with DLD with academic researchers. WHAT THIS PAPER ADDS: What is already known on this subject Developmental Language Disorder (DLD) is characterised by expressive and/or receptive language difficulties in the absence of another biomedical condition that could explain these difficulties. It is critically under-researched and underfunded. As such, there is a lack of public awareness and difficulty recruiting sufficient sample sizes for DLD research studies. What this paper adds to existing knowledge Engage with Developmental Language Disorder (E-DLD) is the first international participant database of individuals with DLD. This paper provides a preliminary report on the profile of linguistic and psychosocial skills among the individuals on the database, adding to current understanding of DLD across age groups. What are the potential or actual clinical implications of this work? Our aim is that the E-DLD will provide much-needed facilitation of research into DLD. E-DLD will enable those with DLD and their families more readily to shape research agendas and to participate in studies that interest them. Families may be recruited into research that could directly translate to better clinical treatment of DLD. We also believe that the E-DLD yearly survey holds potential to provide key information on the development and longitudinal experience of children and adults with DLD.


Assuntos
Transtornos do Desenvolvimento da Linguagem , Criança , Adulto , Humanos , Adolescente , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Transtornos do Desenvolvimento da Linguagem/epidemiologia , Transtornos do Desenvolvimento da Linguagem/terapia , Linguística , Instituições Acadêmicas , Fonoterapia , Emoções
4.
Clin Linguist Phon ; 37(4-6): 513-529, 2023 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-36342206

RESUMO

According to the theory of 'Preferred Argument Structure' (PAS), the realisation and distribution of core arguments including the subject of a transitive verb (A), the direct object of a transitive verb (O) or the subject of an intransitive verb (S) in spoken discourse are subject to both grammatical and pragmatic constraints. However, previous studies on the formulation of argument structure have largely focused on the syntactic difficulties of children with SLI. In addition, little is known about the developmental outcomes in argument structure for adolescents with SLI. In this study, we compared PAS in the narratives of 19 adolescents with SLI (Mean age = 14.3; SD = 0.64) and 19 adolescents with typical language development (TLD; Mean age = 14.5; SD = 0.84). The core arguments of the predicate in each narrative based on the wordless picture storybook 'Frog, where are you?' were coded for grammatical roles (A, O and S), referential forms (lexical forms and non-lexical form including null and pronominal forms) and information status (given, accessible and new information). The data were then analysed for conformity to the grammatical and pragmatic constraints of the PAS theory. The two groups were found to be similar in their conformity to the pragmatic constraints but differed in how they conform to the syntactic constraints. In particular, the adolescents with SLI were more likely to produce clauses with two lexical arguments, and the lexical arguments occurred significantly more frequently at the subject role of a transitive verb than the TLD groups. Our results provide further evidence that it is a persistent grammatical deficit, rather than a pragmatic deficit, which poses a special challenge for adolescents with SLI in their formulation of argument structure in narratives.


Assuntos
Afasia , Desenvolvimento da Linguagem , Criança , Humanos , Adolescente , Narração
5.
Dev Sci ; 24(6): e13112, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34060171

RESUMO

Research has described several features shared between musical rhythm and speech or language, and experimental studies consistently show associations between performance on tasks in the two domains as well as impaired rhythm processing in children with language disorders. Motivated by these results, in the current study our first aim was to explore whether a short exposure to a regular musical rhythm (i.e., rhythmic priming) can improve subsequent grammatical processing in preschool-aged Hungarian-speaking children with and without developmental language disorder (DLD). Second, we investigated whether rhythmic priming is specific to grammar processing by assessing priming in two additional domains: a linguistic but non-grammatical task (picture naming) and a non-linguistic task (nonverbal Stroop task). Third, to confirm that the rhythmic priming effect originates from the facilitating effect of the regular rhythm and not the negative effect of the control condition, we added a third condition, silence, for all the three tasks. Both groups of children showed better performance on the grammaticality judgment task in the regular compared to both the irregular and the silent conditions but no such effect appeared in the non-grammatical and non-linguistic tasks. These results suggest that (1) rhythmic priming can improve grammatical processing in Hungarian, a language with complex morphosyntax, both in children with and without DLD, (2) the effect is specific to grammar and (3) is a result of the facilitating effect of the regular rhythm. These results could motivate further research about integrating rhythmic priming into traditional speech-language therapy. A video abstract of this article can be viewed at https://youtu.be/zKzGuIjZyvU.


Assuntos
Transtornos do Desenvolvimento da Linguagem , Idioma , Criança , Pré-Escolar , Humanos , Hungria , Testes de Linguagem , Linguística , Fala
6.
J Appl Microbiol ; 130(6): 1981-1992, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33190388

RESUMO

AIMS: To genetically engineer the oleaginous yeast Yarrowia lipolytica for de novo production of tetraacetylphytosphingosine (TAPS), a precursor of phytosphingosine, and optimization of fermentation conditions for high yield. METHODS AND RESULTS: We successfully constructed a TAPS-producing Y. lipolytica CE3 strain by co-expression of Wickerhamomyces ciferrii-derived acetyl transferases, Sli1p and Atf2p. Next, we optimized several environmental factors including temperature, initial pH and C/N ratio for TAPS production in a shake culture. Deletion of LCB4 in CE3 strain increased the volumetric TAPS titre and cell-specific yield to 142·1 ± 10·7 mgTAPS  l-1 and 3·08 ± 0·11 mgTAPS  gDCW -1 , respectively, in a shake flask culture incubated for 120 h at 28°C with glycerol as the carbon source. Finally, we developed a 5-l fed-batch process with NaOH-mediated pH control and olive oil as a carbon source, exhibiting 650 ± 24 mgTAPS  l-1 of TAPS production within 56 h of the fermentation. CONCLUSIONS: The introduction of codon-optimized Sli1p and Atf2p, deletion of LCB4 gene and sexual hybridization, accompanied by specific fermentation conditions, enhanced TAPS yield in Y. lipolytica. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results highlight Y. lipolytica as a promising candidate for the industrial production of TAPS, an important component of cosmetic formulations.


Assuntos
Esfingosina/análogos & derivados , Yarrowia/genética , Yarrowia/metabolismo , Técnicas de Cultura Celular por Lotes , Fermentação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Microbiologia Industrial , Engenharia Metabólica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomycetales/enzimologia , Saccharomycetales/genética , Esfingosina/análise , Esfingosina/biossíntese
7.
Clin Linguist Phon ; 34(5): 453-478, 2020 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31496290

RESUMO

This study analyzed narratives from 18 Mandarin-speaking children with specific language impairment (SLI) and 18 typically developing children matched on chronological age. The narrative data were based on Frog, where are you? Participant's narratives were analyzed at the macrostructure and microstructure levels. Regarding the macrostructure, the results revealed that the narratives of children with SLI included significantly less story grammar components, less evaluative comments, and were less coherent than those of TD controls. With respect to the microstructure, the two groups of children exhibited no significant differences in measures such as story length, syntactic complexity, and use of conjunctions; on the other hand, the SLI group employed significantly less variety of words. The outcomes underscore the merit of conducting a wide array of macrostructural measures in narratives, and evince the potential of the causal network model to assess the macrostructure of narratives in SLI. Overall, this study demonstrated the utility of macrostructure and lexical diversity in differentiating Mandarin-speaking children with and without SLI.


Assuntos
Linguística , Narração , Transtorno Específico de Linguagem , Pré-Escolar , Feminino , Humanos , Masculino , Taiwan
8.
Clin Linguist Phon ; 33(1-2): 95-116, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30102084

RESUMO

The current study investigates the role of the morphophonological realisation of grammatical features as a compensatory mechanism for morphosyntactic deficits in specific language impairment (SLI). The phenomenon examined is past tense formation in Standard Modern Greek (SMG) and Cypriot Greek (CG) as it manifests a distinction in morphophonological salience realisation in the two linguistic varieties via differential use of a stress shift and stressed syllabic augment [é] required for past tense rule formation. Participants were pre-schoolers with typical language development (TD) and children with SLI. Subjects produced real verb (RV) and pseudo-verb stimuli (PV) in sentence completion tasks. Results indicated that morphophonological properties of past tense formation affected SLI but not TD performance. We attribute the results to the difference in the status of the augment in each variety and the effects it has on its realisation at the phonetic interface. Furthermore, verb contractibility appeared to pose particular difficulties in the performance of all groups.


Assuntos
Linguagem Infantil , Fonética , Transtorno Específico de Linguagem , Pré-Escolar , Feminino , Grécia , Humanos , Masculino
9.
Clin Linguist Phon ; 33(4): 349-375, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30239228

RESUMO

We aim at determining whether 7-year-old Italian-speaking children with Specific Language Impairment (SLI): (1) have problems with the production of wh- questions; (2) display a subject/object asymmetry in producing which- and who questions; (3) attempt to simplify questions, especially which- questions; (4) have difficulties with movement and verbal agreement in wh- questions. We elicited subject and object who and which NP questions in 10 children with SLI (M = 7;2), in 10 chronological age (CA)-matched controls (M = 7;2) and 10 language-matched controls (M = 5;2). Results showed that (1) children with SLI produced fewer questions than both control groups; (2) a subject/object asymmetry was observed in who questions but not in which NP questions; (3) which NP questions were more problematic than who questions; (4) children with SLI produced more agreement errors and resorted to simplification strategies to avoid wh- question production. Results point to a grammatical deficit due to the computation of complex grammatical relations and suggest that there is a misalignment among pieces of linguistic competence needed to form Italian wh- questions (wh- movement and agreement computation). Outcomes have implications for clinical assessment recommending the production of wh- questions to be considered in the evaluation of SLI in Italian.


Assuntos
Linguagem Infantil , Transtorno Específico de Linguagem , Percepção da Fala , Criança , Feminino , Humanos , Itália , Linguística , Masculino
10.
Clin Linguist Phon ; 33(10-11): 1086-1101, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31017004

RESUMO

Typically, young children diagnosed with specific language impairment (SLI; also called Developmental language disorder, DLD) have been found to show weakness in narrative development, and such weakness has been judged to be unlikely to resolve over time. However, developmental outcomes for adolescents with a prior SLI diagnosis have not been thoroughly studied. In particular, studies on the evaluative aspects of narratives of such persons are almost non-existent. Here we examine the question whether narrative evaluation of adolescents formerly diagnosed with SLI remains problematic into adolescence or comes to resemble more typical narrative performance. We compare the use of evaluative expressions in the narratives of 19 adolescents diagnosed with SLI against 19 typically language developing (TLD) peers. Spoken narratives by the SLI group (Mean age = 14.3; SD = 0.64) and TLD group (Mean age = 14.5; SD = 0.84) using the wordless picture storybook "Frog, where are you?" ( https://childes.talkbank.org/access/Clinical-MOR/Conti/Conti4.html ) were analysed. Each narrative was coded for evaluative clauses, types of evaluative devices (frames of mind, character speech, hedges, negatives, and causal connectives), as well as evaluative perspectives (global vs. local). Although the quantitative analysis did not reveal any significant differences between the two groups, the qualitative analysis showed certain notable strengths in the narrative skills of the focal group of SLI adolescents. Results suggest that adolescents with a history of SLI may approximate TLD narrative skill in evaluating their own narratives, but additional work with more sensitive measures applied at intervals are needed to illuminate developmental pathways of narrative production and of evaluative capacities in adolescents formerly diagnosed with SLI.


Assuntos
Narração , Transtorno Específico de Linguagem/terapia , Adolescente , Estudos de Casos e Controles , Emoções , Feminino , Humanos , Masculino , Transtorno Específico de Linguagem/psicologia
11.
Balkan J Med Genet ; 22(1): 49-56, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31523620

RESUMO

Specific language impairment (SLI) is a psychiatric condition with a complex etiology and a substantial genetic basis that affects children's verbal communication abilities. In this study, we examined the expression of five different human endogenous retrovirus elements (HERVs) in a cohort of 25 children with SLI and 25 healthy children in the control group. Human endogenous retrovirus elements, a diverse group of repetitive DNA sequences, can potentially cause considerable genetic heterogeneity. They had been integrated in the genome of our ancestors throughout evolution and now consist of about 8.0% of the human genome. Several HERV loci are transcribed in various cell types. Their expression in peripheral blood and in the brain is altered in many neurological and psychiatric diseases. To date, HERV expression profiles have never been studied in patients with SLI. This study aimed to elucidate differentially regulated human endogenous retroelements in peripheral blood of children with SLI, in comparison with healthy controls, through quantitative reverse tran-scription-polymerase chain reaction (qRT-PCR) methodology. Our results show that two genes: HERV-K (HLM-2) gag and HERV-P env were expressed at lower levels in the blood samples from SLI children in comparison with those in the control group.

12.
Int J Lang Commun Disord ; 53(3): 643-655, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29575355

RESUMO

BACKGROUND: It has been reported that the inhabitants of the Chilean Robinson Crusoe Island have an increased frequency of specific language impairment (SLI) or developmental language disorder (DLD). AIMS: To explore the familial aggregation of DLD in this community. METHODS & PROCEDURES: We assessed the frequency of DLD amongst colonial children between the ages of 3 and 8;11 years (50 individuals from 45 nuclear families). Familial aggregation rates of language disorder were calculated by assessing all available first-degree relatives (n = 107, 77 parents, 25 siblings, five half-siblings) of the probands. OUTCOMES & RESULTS: We found that 71% of the child population performed significantly below expected in measures of phonological production or expressive and receptive morphology. The majority of these children presented with severe expressive and/or receptive language difficulties. One-quarter of language-disordered probands primarily had phonological difficulties. Family members of affected probands experienced a higher risk of language disorder than those of typically developing probands. This increased risk was apparent regardless of non-verbal IQ. CONCLUSIONS & IMPLICATIONS: The study substantiates the existence of a familial form of speech and language disorder on Robinson Crusoe Island. Furthermore, we find that the familiarity is stable regardless of non-verbal IQ, supporting the recent movement to reduce the importance of non-verbal IQ criterion in DLD diagnoses.


Assuntos
Transtornos do Desenvolvimento da Linguagem/epidemiologia , Criança , Pré-Escolar , Chile/epidemiologia , Chile/etnologia , Feminino , Humanos , Ilhas/epidemiologia , Ilhas/etnologia , Transtornos do Desenvolvimento da Linguagem/etnologia , Transtornos do Desenvolvimento da Linguagem/genética , Masculino , Linhagem , Irmãos , Isolamento Social
13.
Int J Lang Commun Disord ; 53(3): 495-514, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29327801

RESUMO

BACKGROUND: Grammatical morphology has been shown to be problematic for children with specific language impairment (SLI) or developmental language disorder (DLD). Most research on this topic comes from widely spoken languages, such as English. Despite Welsh being the most extensively spoken indigenous in the UK after English, and Wales being the only official bilingual country in the UK, our knowledge about the morphosyntactic areas of Welsh that may pose problems for Welsh-speaking children with SLI is limited. Currently, Welsh-speaking speech and language therapists (SLTs) are heavily reliant on the use of informally translated English assessments. This can inadvertently result in a failure to take aspects of Welsh morphosyntax into account that are critical for the assessment and treatment of Welsh-speaking children. AIMS: This is the first study to examine how Welsh-English bilingual children of early school age with typical development (bi-TD) and with SLI (bi-SLI) perform on production tasks targeting verbal and nominal morphology in Welsh. We targeted areas of Welsh morphosyntax that could potentially be vulnerable for Welsh-speaking children with or at risk of language impairment, such as tense marking and plural formation, and assessed their diagnostic potential. METHODS & PROCEDURES: Twenty-eight Welsh-dominant bilingual children participated in the study: 10 bi-SLI and 18 bi-TD. They were administered three elicitation tasks targeting the production of verbal (compound and synthetic past tense) and nominal (plural) morphology in Welsh. OUTCOMES & RESULTS: The bi-SLI children performed worse than their bi-TD peers across all three tasks. They produced more uninflected verbs in the elicited-production task and were less likely to be prompted to produce the synthetic past, which is a concatenating, low-frequency form of the past tense. They also over-regularized less in the context of plural nouns, and when they did, they opted for high-frequency suffixes. CONCLUSIONS & IMPLICATIONS: By focusing on aspects of morphosyntactic development which are unique to Welsh, we have increased existing about how verbal and nominal morphology are acquired in Welsh-speaking bi-SLI and bi-TD children. The present results point towards productivity problems for Welsh-speaking bi-SLI children who are adversely influenced by low-frequency structures and fail to over-regularize in the context of verbal and nominal concatenating morphology. From a clinical perspective, targeting synthetic past-tense forms through a prompting task may be a promising assessment and intervention tool that future studies could explore further.


Assuntos
Linguagem Infantil , Transtornos do Desenvolvimento da Linguagem/psicologia , Linguística , Multilinguismo , Adolescente , Criança , Pré-Escolar , Inglaterra , Feminino , Humanos , Testes de Linguagem , Masculino , País de Gales
14.
Proc Natl Acad Sci U S A ; 111(38): E3996-4005, 2014 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-25201961

RESUMO

Aurora B kinase regulates the proper biorientation of sister chromatids during mitosis. Lack of Aurora B kinase function results in the inability to correct erroneous kinetochore-microtubule attachments and gives rise to aneuploidy. Interestingly, increased Aurora B activity also leads to problems with chromosome segregation, and overexpression of this kinase has been observed in various types of cancer. However, little is known about the mechanisms by which an increase in Aurora B kinase activity can impair mitotic progression and cell viability. Here, using a yeast model, we demonstrate that increased Aurora B activity as a result of the overexpression of the Aurora B and inner centromere protein homologs triggers defects in chromosome segregation by promoting the continuous disruption of chromosome-microtubule attachments even when sister chromatids are correctly bioriented. This disruption leads to a constitutive activation of the spindle-assembly checkpoint, which therefore causes a lack of cytokinesis even though spindle elongation and chromosome segregation take place. Finally, we demonstrate that this increase in Aurora B activity causes premature collapse of the mitotic spindle by promoting instability of the spindle midzone.


Assuntos
Aurora Quinase B/metabolismo , Cromossomos Fúngicos/metabolismo , Cinetocoros/enzimologia , Microtúbulos/enzimologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Fuso Acromático/enzimologia , Aurora Quinase B/genética , Cromátides/enzimologia , Cromátides/genética , Cromossomos Fúngicos/genética , Microtúbulos/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Fuso Acromático/genética
15.
Int J Lang Commun Disord ; 52(6): 750-765, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28421645

RESUMO

BACKGROUND: A limited number of studies have analyzed grammaticality in monolingual Spanish-speaking children with specific language impairment (SLI). Most of the available data are based on bilingual speakers. AIMS: To extend previous studies by doing a more detailed analysis of grammatical types in monolingual Spanish-speakers with and without SLI. METHODS & PROCEDURES: Forty-nine Spanish-speaking children (18 with SLI, 17 age-matched typically developing controls, 14 language-matched controls) were recruited from schools in Mexico and observed in a spontaneous narrative task. OUTCOMES & RESULTS: The findings were inconsistent with those of previous studies. Significant differences were found for article, connector and preposition omissions, and the per cent of ungrammatical utterances. There were no significant differences found for clitics and verb phrases, though clitic substitutions were frequent. Language-matched controls did not produce different frequencies of ungrammatical utterances. CONCLUSIONS & IMPLICATIONS: Significant differences were found for three main items: the per cent of ungrammatical utterances, the omission of articles and the omission of prepositions. Therefore, we propose these components be taken into consideration when distinguishing typically developing children from children with SLI.


Assuntos
Linguagem Infantil , Transtornos da Linguagem/psicologia , Idioma , Grupo Associado , Fala , Fatores Etários , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Transtornos da Linguagem/diagnóstico , Testes de Linguagem , Masculino , México , Medida da Produção da Fala , Vocabulário
16.
Int J Lang Commun Disord ; 52(3): 311-322, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27511872

RESUMO

BACKGROUND: Past research with children with specific language impairment (SLI) has shown them to have poorer planning and problem-solving ability, and delayed self-regulatory speech (SRS) relative to their typically developing (TD) peers. However, the studies are few in number and are restricted in terms of the number and age range of participants, which limits our understanding of the nature and extent of any delays. Moreover, no study has examined the performance of a significant subset of children with SLI, those who have hyperactive and inattentive behaviours. AIMS: This cross-sectional study aimed to compare the performance of young children with SLI (aged 4-7 years) with that of their TD peers on a planning and problem-solving task and to examine the use of SRS while performing the task. Within each language group, the performance of children with and without hyperactive and inattentive behaviours was further examined. METHODS & PROCEDURES: Children with SLI (n = 91) and TD children (n = 81), with and without hyperactive and inattentive behaviours across the three earliest school years (Kindergarten, Preprimary and Year 1) were video-taped while they completed the Tower of London (TOL), a planning and problem-solving task. Their recorded speech was coded and analysed to look at differences in SRS and its relation to TOL performance across the groups. MAIN CONTRIBUTION: Children with SLI scored lower on the TOL than TD children. Additionally, children with hyperactive and inattentive behaviours performed worse than those without hyperactive and inattentive behaviours, but only in the SLI group. This suggests that children with SLI with hyperactive and inattentive behaviours experience a double deficit. Children with SLI produced less inaudible muttering than TD children, and showed no reduction in social speech across the first three years of school. Finally, for children with SLI, a higher percentage performed better on the TOL when they used SRS than when they did not. CONCLUSIONS & IMPLICATIONS: The results point towards a significant delay in the development and internalization of SRS in the SLI group, which should be taken into account when considering the planning and problem-solving of young children with SLI.


Assuntos
Formação de Conceito , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Transtornos do Desenvolvimento da Linguagem/psicologia , Resolução de Problemas , Autocontrole , Distúrbios da Fala/diagnóstico , Distúrbios da Fala/psicologia , Criança , Pré-Escolar , Comunicação , Feminino , Humanos , Terapia da Linguagem , Masculino , Avaliação de Resultados em Cuidados de Saúde , Grupo Associado , Valores de Referência , Medida da Produção da Fala , Fonoterapia , Comportamento Verbal
17.
Brain Topogr ; 29(3): 459-76, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26671710

RESUMO

Detecting and discriminating subtle and rapid sound changes in the speech environment is a fundamental prerequisite of language processing, and deficits in this ability have frequently been observed in individuals with language-learning impairments (LLI). One approach to studying associations between dysfunctional auditory dynamics and LLI, is to implement a training protocol tapping into this potential while quantifying pre- and post-intervention status. Event-related potentials (ERPs) are highly sensitive to the brain correlates of these dynamic changes and are therefore ideally suited for examining hypotheses regarding dysfunctional auditory processes. In this study, ERP measurements to rapid tone sequences (standard and deviant tone pairs) along with behavioral language testing were performed in 6- to 9-year-old LLI children (n = 21) before and after audiovisual training. A non-treatment group of children with typical language development (n = 12) was also assessed twice at a comparable time interval. The results indicated that the LLI group exhibited considerable gains on standardized measures of language. In terms of ERPs, we found evidence of changes in the LLI group specifically at the level of the P2 component, later than 250 ms after the onset of the second stimulus in the deviant tone pair. These changes suggested enhanced discrimination of deviant from standard tone sequences in widespread cortices, in LLI children after training.


Assuntos
Deficiências da Aprendizagem/fisiopatologia , Deficiências da Aprendizagem/terapia , Aprendizagem/fisiologia , Percepção da Fala/fisiologia , Estimulação Acústica/métodos , Recursos Audiovisuais , Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Córtex Cerebral/fisiologia , Criança , Eletroencefalografia , Potenciais Evocados/fisiologia , Potenciais Evocados Auditivos , Feminino , Humanos , Idioma , Testes de Linguagem , Masculino , Percepção da Altura Sonora/fisiologia
18.
Int J Lang Commun Disord ; 51(5): 581-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26992032

RESUMO

BACKGROUND: Specific language impairment (SLI) is heterogeneous and identifying subgroups within it may help explain the aetiology of the condition. Phonological processing abilities distinguish between children with SLI who do and do not have reading decoding impairments (RDIs). AIMS: To probe different levels of phonological processing in children with SLI with and without RDI to investigate the cognitive basis of these differences. METHODS & PROCEDURES: A total of 64 children aged 5-17 years were classified using the results of standardized language and single-word reading tests into those with no SLI and no RDI (No SLI/No RDI) (N = 18), no SLI but with RDI (No SLI/RDI) (N = 4, not included in analyses because of the small number), SLI/No RDI (N = 20), and SLI/RDI (N = 22). The groups were compared on a range of tasks engaging different levels of phonological processing (input and output processing and phonological awareness). OUTCOMES & RESULTS: The SLI/RDI group was distinguished from the SLI/No RDI and No SLI/No RDI groups by more errors in the longer items in non-word repetition and by poorer phonological awareness. Non-word discrimination scores indicated a gradient of performance across groups that was not associated with a qualitatively different pattern of performance. CONCLUSIONS & IMPLICATIONS: This is the first study contrasting input and output processes associated with phonological processing. The results suggest that deficits in SLI plus RDI may be associated with impairment in actively maintaining phonological representations for phonological processing, which is not present in those without RDI and which leads to reading decoding difficulties.


Assuntos
Dislexia , Transtornos do Desenvolvimento da Linguagem , Leitura , Adolescente , Criança , Pré-Escolar , Cognição , Feminino , Humanos , Testes de Linguagem , Masculino , Fonética
19.
Int J Lang Commun Disord ; 51(2): 203-11, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26541806

RESUMO

BACKGROUND: To date very few studies have investigated the musical skills of children with specific language impairment (SLI). There is growing evidence that SLI affects areas other than language, and it is therefore reasonable to hypothesize that children with this disorder may have difficulties in perceiving musical stimuli appropriately. AIMS: To compare melody and song identification skills in a group of children with SLI and in a control group of children with typical language development (TD); and to study possible correlations between music identification skills and language abilities in the SLI group. METHODS & PROCEDURES: This is a prospective case control study. Two groups of children were enrolled: one meeting DSM-IV-TR(®) diagnostic criteria for SLI and the other comprising an age-matched group of children with TD. All children received a melody and a song identification test, together with a test battery assessing receptive and productive language abilities. OUTCOMES & RESULTS: 30 children with SLI (mean age = 56 ± 9 months) and 23 with TD (mean age = 60 ± 10 months) were included. Melody and song identification scores among SLI children were significantly lower than those of TD children, and in both groups song identification scores were significantly higher than melody identification scores. Song identification skills bore a significant correlation to chronological age in both groups (TD: r = 0.529, p = 0.009; SLI: r = 0.506, p = 0.004). Whereas no other variables were found explaining the variability of melody or song identification scores in either group, the correlation between language comprehension and song identification in the SLI group approached significance (r = 0.166, p = 0.076). CONCLUSIONS & IMPLICATIONS: The poorer music perception skills of SLI children as compared with TD ones suggests that SLI may also affect music perception. Therefore, training programmes that simultaneously stimulate via language and music may prove useful in the rehabilitation of children affected by SLI.


Assuntos
Transtornos do Desenvolvimento da Linguagem/diagnóstico , Transtornos do Desenvolvimento da Linguagem/psicologia , Música , Reconhecimento Psicológico , Estudos de Casos e Controles , Pré-Escolar , Feminino , Humanos , Testes de Linguagem/estatística & dados numéricos , Masculino , Estudos Prospectivos , Psicometria , Valores de Referência , Estatística como Assunto
20.
Int J Lang Commun Disord ; 51(1): 61-73, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26132884

RESUMO

BACKGROUND: Children with specific language impairment (SLI) often experience word-learning difficulties, which are suggested to originate in the early stage of word learning: fast mapping. Some previous research indicates significantly poorer fast mapping capabilities in children with SLI compared with typically developing (TD) counterparts, with a range of methodological factors impacting on the consistency of this finding. Research has explored key issues that might underlie fast mapping difficulties in children with SLI, with strong theoretical support but little empirical evidence for the role of phonological short-term memory (STM). Additionally, further research is required to explore the influence of receptive vocabulary on fast mapping capabilities. Understanding the factors associated with fast mapping difficulties that are experienced by children with SLI may lead to greater theoretically driven word-learning intervention. AIMS: To investigate whether children with SLI demonstrate significant difficulties with fast mapping, and to explore the related factors. It was hypothesized that children with SLI would score significantly lower on a fast mapping production task compared with TD children, and that phonological STM and receptive vocabulary would significantly predict fast mapping production scores in both groups of children. METHODS & PROCEDURES: Twenty-three children with SLI (mean = 64.39 months, SD = 4.10 months) and 26 TD children (mean = 65.92 months, SD = 2.98) were recruited from specialist language and mainstream schools. All participants took part in a unique, interactive fast-mapping task whereby nine novel objects with non-word labels were presented and production accuracy was assessed. A non-word repetition test and the Peabody Picture Vocabulary Test-Fourth Edition (PPVT-IV) were also administered as measures of phonological STM capacity and receptive vocabulary, respectively. OUTCOMES & RESULTS: Results of the fast-mapping task indicated that children with SLI had significantly poorer fast mapping production scores than TD children. Scores from the non-word repetition task were also significantly lower for the SLI group, revealing reduced phonological STM capacity. Phonological STM capacity and receptive vocabulary emerged as significant predictors of fast mapping performance when the group data were combined in a multiple regression analysis. CONCLUSIONS & IMPLICATIONS: These results suggest that the word-learning difficulties experienced by children with SLI may originate at the fast mapping stage, and that phonological STM and receptive vocabulary significantly predict fast mapping ability. These findings contribute to the theoretical understanding of word-learning difficulties in children with SLI and may inform lexical learning intervention.


Assuntos
Transtornos do Desenvolvimento da Linguagem/diagnóstico , Transtornos do Desenvolvimento da Linguagem/terapia , Terapia da Linguagem , Memória de Curto Prazo , Percepção da Fala , Aprendizagem Verbal , Vocabulário , Pré-Escolar , Feminino , Humanos , Masculino , Reconhecimento Visual de Modelos , Semântica , Medida da Produção da Fala
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