Susceptibility genes and neurodevelopmental mechanisms in dyslexia

Developmental dyslexia is a specific reading disability, which is characterised by unexpected difficulty in reading, spelling and writing despite adequate intelligence, education and social environment. It is the most common childhood learning disorder affecting 5-10 % of the population and thus constitutes the largest portion of all learning disorders. It is a persistent developmental failure although it can be improved by compensation. According to the most common theory, the deficit is in phonological processing, which is needed in reading when the words have to be divided into phonemes, or distinct sound elements. This occurs in the lowest level of the hierarchy of the language system and disturbs processes in higher levels, such as understanding the meaning of words. Dyslexia is a complex genetic disorder and previous studies have found nine locations in the genome that associate with it. Altogether four susceptibility genes have been found and this study describes the discovery of the first two of them, DYX1C1 and ROBO1. The first clues were obtained from two Finnish dyslexic families that have chromosomal translocations which disrupt these genes. Genetic analyses supported their role in dyslexia: DYX1C1 associates with dyslexia in the Finnish population and ROBO1 was linked to dyslexia in a large Finnish pedigree. In addition a genome-wide scan in Finnish dyslexic families was performed. This supported the previously detected dyslexia locus on chromosome 2 and revealed a new locus on chromosome 7. Dyslexia is a neurological disorder and the neurobiological function of the susceptibility genes DYX1C1 and ROBO1 are consistent with this. ROBO1 is an axon guidance receptor gene, which is involved in axon guidance across the midline in Drosophila and axonal pathfinding between the two hemispheres via the corpus callosum, as well as neuronal migration in the brain of mice. The translocation and decreased ROBO1 expression in dyslexic individuals indicate that two functional copies of ROBO1 gene are required in reading. DYX1C1 was a new gene without a previously known function. Inhibition of Dyx1c1 expression showed that it is needed in normal brain development in rats. Without Dyx1c1 protein, the neurons in the developing brain will not migrate to their final position in the cortex. These two dyslexia susceptibility genes DYX1C1 and ROBO1 revealed two distinct neurodevelopmental mechanisms of dyslexia, axonal pathfinding and neuronal migration. This study describes the discovery of the genes and our research to clarify their role in developmental dyslexia.

A escrita alfabética, sua natureza e representação: contribuições à Fonoaudiologia aplicada à Educação

Introdução: Essa pesquisa situa-se no campo epistemológico da Fonoaudiologia Educacional. A prática fonoaudiológica no Brasil tem sua gênese vinculada a medidas de uniformização e normatização da língua. As ações fonoaudiológicas foram, desde a sua origem, influenciadas pelo positivismo e pelo pensamento naturalista, o que se traduziu em uma atuação, marcadamente, clínico-médica e numa concepção normativa de desenvolvimento e aprendizagem da escrita. Esforços têm sido empreendidos para se instituir no campo educacional uma atuação fonoaudiológica diferenciada, que se destitua do caráter curativo e normativo e se volte para a promoção do processo de ensino-aprendizagem. No entanto, apesar dos esforços em busca da modificação e ampliação da atuação fonoaudiológica educacional, esse caráter clínico-médico persiste. Entende-se que tal perpetuação é sustentada por paradigmas enraizados e mantidos até hoje na formação do fonoaudiólogo e do educador. Trata-se de visões que universalizam questões relativas à linguagem e ao processo de aprendizagem da escrita e medicalizam padrões que se apresentam fora do esperado como normalidade. Objetivo: Caracterizar a natureza e a representação da escrita alfabética, visando a contribuir para a superação da cultura naturalística e biologizante na abordagem das questões sobre a aprendizagem e o domínio da língua escrita no campo da Fonoaudiologia Educacional. Metodologia: Pesquisa científica de base teórico-conceitual. Resultados: Essa pesquisa revela que o sistema estrutural da escrita constitui um fenômeno com propriedades gramaticais e representacionais que se distinguem da fala. Evidencia-se que a relação entre a língua escrita e a língua oral não é direta, de tal modo que a escrita alfabética não é uma transcodificação da fala. Além disso, essa tese sustenta que a natureza da escrita não é biológica, mas eminentemente cultural, de tal maneira que sua apropriação e domínio constituem um processo conceitual singular. Tal concepção implica o entendimento de que diferentes sujeitos socioculturais interagem e conceituam a escrita de modos diversos. Essa diversidade ocorre porque sujeitos sociais plurais apresentam modos diferenciados de organização e operação mental que, por sua vez, implicam diferentes formas de interação com o mundo, com o outro e com a escrita, resultando em diferenças individuais na estruturação e no uso da fala e da escrita. A partir desses conceitos, sistematizam-se princípios norteadores para a constituição de uma atuação fonoaudiológica educacional, no campo da escrita, destituída de qualquer caráter clínicomédico. Conclusões: O entendimento de que a apropriação da escrita não tem natureza biológica permite a compreensão de que os diferentes modos de escrita não podem ser validados por regras universais baseadas em um sistema mental apriorístico, nem, tampouco, considerados produtos de uma condição de anormalidade intrínseca ao sujeito. Essa tese demonstrou que a manutenção de uma concepção de um determinismo biológico para as dificuldades na aprendizagem ou domínio da escrita, na verdade, envolve uma questão paradigmática. Enfim, os parâmetros que definem as categorias do que é normal e do que é anormal na estruturação e no uso da escrita não são regidos por princípios biológicos, mas por categorias paradigmáticas. Assim, a ideia de um distúrbio de aprendizagem da escrita se sustenta somente sob determinado paradigma.

汉语发展性阅读障碍儿童的视觉大细胞通路特点

Developmental dyslexia (DD) is a common kind of learning disorder, which affects 5-18% of people. It seems important to explore the deficit in visual magnocellular pathway in Chinese developmental dyslexia, for many researches demonstrated that one of the core deficits of Chinese developmental dyslexia was orthographic deficit which was associated with the deficit in visual magnocellular pathway. Two studies were done to detect the differences among Chinese developmental dyslexics, average readers of the same chronological age (CA controls) and average readers of the same reading level (RL controls) in reaction time, accuracy and visual mismatch negativity (vMMN) elicited by the moving gratings responded by visual magnocellular pathway. There were two grating-conditions which were low contrast/low spatial frequency condition and high contrast/high spatial frequency condition respectively. In ERP study, a modified “cross-modal delayed response” paradigm was used to elicit the vMMN. The results showed that the developmental dyslexics responded slower than CA controls, had more errors than RL controls, and had smaller amplitudes of vMMNs than the two controls in visual magnocellular pathway condition, but not in control condition. That is to say, Chinese developmental dyslexics had deficits in visual magnocellular pathway.

Dificuldades de aprendizagem na leitura e na escrita: o contributo de jogos eletrónicos na motivação e na aprendizagem

Projeto de Intervenção apresentado à Escola Superior de Educação de Lisboa para obtenção do grau de Mestre em Educação Especial, Especialização em Problemas de Aprendizagem e Comportamento

Le travail de l’orthopédagogue quant au dépistage, à la référence et à la prise en charge d’un trouble spécifique d’apprentissage en lecture

Les difficultés reliées à la lecture constituent 80% des motifs de référence en orthopédagogie. Parfois, ces difficultés sont les précurseurs du trouble d’apprentissage le plus commun soit le trouble spécifique d’apprentissage en lecture (TSAL). Cette recherche porte sur le travail des orthopédagogues en lien avec les trois grandes étapes reliées au TSAL : (1) son dépistage, (2) son évaluation orthopédagogique et sa référence en neuropsychologie et finalement (3) sa prise en charge ainsi que sa rééducation en lien avec les recommandations neuropsychologiques. La collecte de données a été réalisée grâce à des entrevues avec trois orthopédagogues travaillant au primaire et autour d’un cas d’élève atteint de TSAL. Chacune des trois orthopédagogues a présenté un cas d’élève et a décrit sa pratique. Lors des rencontres, chaque participante a également remis au chercheur le dossier de l’élève contenant le rapport neuropsychologique confirmant le diagnostic. Les résultats de cette recherche indiquent que les signes précurseurs observés par les trois orthopédagogues ainsi que leurs interventions rééducatives sont très semblables. Toutefois, les outils d’évaluation utilisés diffèrent de l’une à l’autre tant en ce qui a trait au choix qu’à la manière de les utiliser. Les trois orthopédagogues optent pour la référence en neuropsychologie dans le but ultime de dresser un portrait global de leur élève quant à leurs habiletés cognitives et déficitaires pouvant être attribuables à un TSAL. Le rapport du neuropsychologue sert alors à confirmer l’impression diagnostique des orthopédagogues. Les résultats de notre étude montrent que les orthopédagogues entament de façon précoce les interventions rééducatives et offrent simultanément les mesures adaptatives relatives aux difficultés observées chez l’élève. Avec l’arrivée du diagnostic de TSAL, et les recommandations proposées dans le rapport neuropsychologique, les orthopédagogues valident et peuvent à l’occasion bonifier leurs interventions ou mesures. De plus, elles les officialisent en les ajoutant, si ce n’est pas déjà fait, au plan d’intervention de l’élève. Les interventions rééducatives et les mesures adaptées mises en place par les trois orthopédagogues sont également comparées à celles proposées par les neuropsychologues et analysées à la lumière de celles reconnues comme étant efficaces et profitables selon la littérature. Nos résultats mettent en évidence la grande similitude qui existe entre les interventions appliquées par les orthopédagogues, celles proposées par les neuropsychologues ainsi que celles répertoriées dans la littérature.

Desempenho de escolares com distúrbio de aprendizagem e dislexia em testes de processamento auditivo

OBJETIVO: caracterizar e comparar, por meio de testes comportamentais, o processamento auditivo de escolares com diagnóstico interdisciplinar de (I) distúrbio da aprendizagem, (II) dislexia e (III) escolares com bom desempenho acadêmico. MÉTODOS: participaram deste estudo 30 escolares na faixa etária de 8 a 16 anos de idade, de ambos os gêneros, de 2ª a 4ª séries do ensino fundamental, divididos em três grupos: GI composto por 10 escolares com diagnóstico interdisciplinar de distúrbio de aprendizagem, GII: composto por 10 escolares com diagnóstico interdisciplinar de dislexia e GIII composto por 10 escolares sem dificuldades de aprendizagem, pareados segundo gênero e faixa etária com os grupos GI e GII. Foram realizadas avaliação audiológica e de processamento auditivo. RESULTADOS: os escolares de GIII apresentaram desempenho superior nos testes de processamento auditivo em relação aos escolares de GI e GII. GI apresentou desempenho inferior nas habilidades auditivas avaliadas para testes dicóticos de dígitos e dissílabos alternados, logoaudiometria pediátrica, localização sonora, memória verbal e não-verbal, ao passo que GII apresentou as mesmas alterações de GI, com exceção do teste de logoaudiometria pediátrica. CONCLUSÃO: os escolares com transtornos de aprendizagem apresentaram desempenho inferior nos testes de processamento auditivo, sendo que os escolares com distúrbio de aprendizagem apresentaram maior número de habilidades auditivas alteradas, em comparação com os escolares com dislexia, por terem apresentado atenção sustentada reduzida. O grupo de escolares com dislexia apresentou alterações decorrentes da dificuldade relacionada à codificação e decodificação de estímulos sonoros.

Desempenho de escolares com transtorno de déficit de atenção e hiperatividade em tarefas metalinguisticas e de leitura

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Velocardiofacial syndrome with a rare t(2;22)

Rearrangements involving chromosomes 2 and 22 were described not only as acquired abnormalities in a variety of human neoplasias but also in the constitutional karyotype suggesting the existence of a greater fragility in some specific regions in these chromosomes. Patients with DiGeorge and Velocardiofacial syndromes have a deletion on 22q11 leading to haploinsufficiency for one or more gene(s). We report a patient with velocardiofacial syndrome in which cytogenetic and fluorescence in situ hybridization analysis showed a rare t(2;22) and deletion in the 22q11 region. © 2007 Lippincott Williams & Wilkins, Inc.

Desenvolvimento psicomotor e as dificuldades de aprendizagem escolar em crianças de 5 a 8 anos: representações de professores

Pós-graduação em Psicologia - FCLAS

Desempenho de escolares com e sem transtorno de aprendizagem em leitura, escrita, consciência fonológica, velocidade de processamento e memória de trabalho fonológica

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Potenciais evocados auditivos de longa latência em escolares com transtornos específicos de aprendizagem

Purpose: To study the components of long latency auditory evoked potentials and to compare data from these measures in students with and without learning disabilities. Method: Thirty students, 15 with learning disorder (study group) and 15 typical without learning problems (control group), of both genders, aged 7-14 years, mean age 10 years. They underwent clinical assessment in a clinic belonging to a public university in the state of São Paulo. Following, audiological assessment was performed to determine normal peripheral auditory system and electrophysiological assessment by examining the long latency auditory evoked response. Result: The results showed that there are functional differences between the groups. Increased latency components of long latency auditory evoked potential was observed in the study group compared to the control group. Longer latency values of these components were observed in the left ear when stimulated in the study group. Conclusion: This study contributed to better understanding of the auditory pathway functioning in children with learning disorders and can be a reference for other clinical and experimental studies and thus improve the definition of diagnostic criteria in this population.

Potencial Cognitivo Auditivo e vectoeletronistagmografia em escolares com dislexia e distúrbios de aprendizagem

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Studio di ausili tecnologici compensativi di supporto all'iter di apprendimento matematico secondario e universitario degli studenti con dislessia

Data coming out from various researches carried out over the last years in Italy on the problem of school dispersion in secondary school show that difficulty in studying mathematics is one of the most frequent reasons of discomfort reported by students. Nevertheless, it is definitely unrealistic to think we can do without such knowledge in today society: mathematics is largely taught in secondary school and it is not confined within technical-scientific courses only. It is reasonable to say that, although students may choose academic courses that are, apparently, far away from mathematics, all students will have to come to terms, sooner or later in their life, with this subject. Among the reasons of discomfort given by the study of mathematics, some mention the very nature of this subject and in particular the complex symbolic language through which it is expressed. In fact, mathematics is a multimodal system composed by oral and written verbal texts, symbol expressions, such as formulae and equations, figures and graphs. For this, the study of mathematics represents a real challenge to those who suffer from dyslexia: this is a constitutional condition limiting people performances in relation to the activities of reading and writing and, in particular, to the study of mathematical contents. Here the difficulties in working with verbal and symbolic codes entail, in turn, difficulties in the comprehension of texts from which to deduce operations that, once combined together, would lead to the problem final solution. Information technologies may support this learning disorder effectively. However, these tools have some implementation limits, restricting their use in the study of scientific subjects. Vocal synthesis word processors are currently used to compensate difficulties in reading within the area of classical studies, but they are not used within the area of mathematics. This is because the vocal synthesis (or we should say the screen reader supporting it) is not able to interpret all that is not textual, such as symbols, images and graphs. The DISMATH software, which is the subject of this project, would allow dyslexic users to read technical-scientific documents with the help of a vocal synthesis, to understand the spatial structure of formulae and matrixes, to write documents with a technical-scientific content in a format that is compatible with main scientific editors. The system uses LaTex, a text mathematic language, as mediation system. It is set up as LaTex editor, whose graphic interface, in line with main commercial products, offers some additional specific functions with the capability to support the needs of users who are not able to manage verbal and symbolic codes on their own. LaTex is translated in real time into a standard symbolic language and it is read by vocal synthesis in natural language, in order to increase, through the bimodal representation, the ability to process information. The understanding of the mathematic formula through its reading is made possible by the deconstruction of the formula itself and its “tree” representation, so allowing to identify the logical elements composing it. Users, even without knowing LaTex language, are able to write whatever scientific document they need: in fact the symbolic elements are recalled by proper menus and automatically translated by the software managing the correct syntax. The final aim of the project, therefore, is to implement an editor enabling dyslexic people (but not only them) to manage mathematic formulae effectively, through the integration of different software tools, so allowing a better teacher/learner interaction too.

Análisis sistemático de pautas para la accesibilidad TIC para personas con discapacidad cognitiva

Este trabajo de investigación presenta los resultados de una revisión sistemática realizada a partir de la recopilación, lectura y análisis de distintas fuentes bibliográficas dentro de un conjunto heterogéneo consistente de 175 estudios que forman la base bibliográfica actual del documento “Cognitive Accessibility User Research” (W3C, 2015a) del W3C. Esta base bibliográfica está compuesta por publicaciones científicas basadas en libros, artículos, conferencias y sitios Web especializados, en los cuales se potencia como objeto particular de análisis, la indagación en la búsqueda de pautas de accesibilidad en las tecnologías Web que apoyen la integración a personas con discapacidad cognitiva. Como parte de este proceso de investigación se ha recopilado y descrito la situación actual, particularmente, de los retos en la utilización de las tecnologías de la información y la comunicación (TIC) en relación a personas con dificultades de aprendizaje o discapacidades cognitivas, tales como la Dislexia, Afasia, Trastorno de Aprendizaje No verbal, Envejecimiento-Demencia, Trastornos por Déficit de Atención con o sin Hiperactividad, Autismo, Síndrome de Down y Discalculia. Como aporte primordial de este Trabajo Fin de Master (TFM), se intenta trazar una línea de criterios que permitan la evaluación objetiva de este tópico, con miras a ofrecer un enfoque práctico y reciente sobre ésta temática, mostrando de forma esquematizada las pautas existentes y sirviendo de síntesis orientativa para el diseño accesible de las TIC con la finalidad de promover un soporte real a personas con los tipo de discapacidad cognitiva en los que se ha enfocado esta investigación. Logrando obtener como resultado principal de este estudio, 36 pautas generales que agrupan las coincidencias del grupo de discapacidades estudiadas y que han sido distribuidas en categorías: texto, navegación y generales, para su mejor interpretación y manejo de la Accesibilidad en las TIC´S para Personas con Discapacidad Cognitiva.---ABSTRACT---This research presents the results of a systematic review from collecting, reading and analysis of different bibliographic sources within a heterogeneous group consisting of 175 studies that form the basis of current literature document "Accessibility User Cognitive Research" (W3C , 2015th) of the W3C. This bibliographic database is composed of scientific publications based on books, articles, lectures and specialized Web sites, in which is enhanced as a particular object of analysis, the inquiry into the search for accessibility guidelines for Web technologies to support integration of people with cognitive disabilities. As part of this research process, the current situation has been collected and described, particularly the challenges in the use of information and communications technology (ICT) in relation to people with learning disabilities or cognitive disabilities, such as Dyslexia, aphasia, nonverbal learning disorder, aging-Dementia, Attention Deficit Disorders with or without hyperactivity, autism, Down syndrome and dyscalculia. As primary contribution of this Master's Thesis (TFM), it tries to draw a line of criteria to allow an objective assessment of this topic, in order to provide a practical and recent focus on this theme, showing schematically existing guidelines and serving as guidance for accessible design of ICT in order to promote a real support to people with cognitive disabilities where this research has focused on. Managing to obtain the main result of this study, 36 general guidelines that group the set of disabilities studied and have been distributed in categories: text, navigation and general, for better interpretation and management of ICTs for Accessibility people with cognitive disabilities.

O saber na perspectiva psicanalítica de orientação freudo-lacaniana: um estudo teórico

This work came from a research question, namely authorizing a child to learn, lifted from the care of a child of 09 years in the school service of a private university located in Natal, whose complaint referred to a learning disorder more specifically, not the formalization of reading and writing. To undertake a survey of the Lacanian psychoanalytic - Freudian literature on learning, we find the concept of knowledge as fundamental to the analysis of this issue which led us to investigate the history of its co nstruction in Freud and Lacan, with a view to shed light on their relationship to learn. This is a theoretical type of research with the proposal to revisit the concept of knowledge in the work of Freud and Lacan's teaching, in which case only served as th e trigger point of this work. We found that in both these authors, the concept of knowledge is associated to the unconscious exclusively and can be hinged to learn the way of the desire to know. It concludes that learning is a process that involves the unconscious knowledge. Consequently, learning disorders may be linked to the impossible into play in the know about the desire to find himself alienated the significant of what operates as forbidden to know when not referred only or also of teaching and / or educational aspects. This shows us that the complaints that come to the clinic can illustrate dilemmas experienced by the speaking, related to subjective questions. Deviations from the possibility of learning may indicate in these cases, a manifestation of what is singular and very impossibility of generalization when it comes to subjects. With this, also attest that the relations of the subject with knowledge effect in learning processes.