Dyslexia. 2010 Aug;16(3):240-57.

On the importance of anchoring and the consequences of its impairment in dyslexia.

Banai K, Ahissar M.

University of Haifa, Communication Sciences and Disorders, Haifa, Israel.

Abstract

One of the main impediments of individuals with reading difficulties and individuals with language difficulties is poor working memory. Typically measured using verbal stimuli, working memory deficits have often been considered as one aspect of the phonological difficulty putatively underlying dyslexia. Over the years it has been shown that a broad range of auditory discrimination abilities are also mildly impaired. Here we present evidence that a domain general, rather than a phonology specific, deficits in the ability to implicitly use contextual information, which we term anchoring, can account for both types of deficits. We propose that anchoring ability, which reflects a basic biological mechanism for replacing effortful mechanisms of explicit working memory with automatic mechanisms of implicit memory, and consequently boost performance in both perceptual and cognitive tasks, is a crucial factor in our ability to be expert users of oral and written language. Copyright (c) 2010 John Wiley & Sons, Ltd.

Message édité par : AnneNhauneem / 06-08-2010 17:06

Dyslexia. 2010 Aug;16(3):213-25.

Developmental dyslexia and explicit long-term memory.

Menghini D, Carlesimo GA, Marotta L, Finzi A, Vicari S.

Department of Neuroscience, I.R.C.C.S. Children's Hospital Bambino Gesù, Rome, Italy.

Abstract

The reduced verbal long-term memory capacities often reported in dyslexics are generally interpreted as a consequence of their deficit in phonological coding.The present study was aimed at evaluating whether the learning deficit exhibited by dyslexics was restricted only to the verbal component of the long-term memory abilities or also involved visual-object and visual-spatial domain. A further goal of the present study was to investigate the predictive value of non-verbal long-term memory abilities with respect to word and non-word reading in dyslexic children.In accordance with these aims, performances of 60 dyslexic children were compared with that of 65 age-matched normal readers on verbal, visual-spatial and visual-object task.Results documented a generalized impairment of episodic long-term memory capacities in dyslexic children and the results did not vary as a function of children's age.Furthermore, in addition to verbal measures, also individual differences in non-verbal long-term memory tasks turn out to be good predictors of reading difficulties in dyslexics.Our findings indicate that the long-term memory deficit in dyslexia is not limited to the dysfunction of phonological components but also involves visual-object and visual-spatial aspect, thus suggesting that dyslexia is associated to multiple cognitive deficits. Copyright (c) 2010 John Wiley & Sons, Ltd.

Message édité par : AnneNhauneem / 06-08-2010 17:09

Dyslexia. 2010 Aug;16(3):194-212.

Procedural learning and dyslexia.

Nicolson RI, Fawcett AJ, Brookes RL, Needle J.

Department of Psychology, University of Sheffield, Sheffield, UK.

Abstract

Three major 'neural systems', specialized for different types of information processing, are the sensory, declarative, and procedural systems. It has been proposed (Trends Neurosci., 30(4), 135-141) that dyslexia may be attributable to impaired function in the procedural system together with intact declarative function. We provide a brief overview of the increasing evidence relating to the hypothesis, noting that the framework involves two main claims: first that 'neural systems' provides a productive level of description avoiding the underspecificity of cognitive descriptions and the overspecificity of brain structural accounts; and second that a distinctive feature of procedural learning is its extended time course, covering from minutes to months. In this article, we focus on the second claim. Three studies-speeded single word reading, long-term response learning, and overnight skill consolidation-are reviewed which together provide clear evidence of difficulties in procedural learning for individuals with dyslexia, even when the tasks are outside the literacy domain. The educational implications of the results are then discussed, and in particular the potential difficulties that impaired overnight procedural consolidation would entail. It is proposed that response to intervention could be better predicted if diagnostic tests on the different forms of learning were first undertaken. Copyright (c) 2010 John Wiley & Sons, Ltd.

PMID: 20680991

Message édité par : AnneNhauneem / 06-08-2010 17:14

Quelqu'un a til les compétence pour traduire???? :#

GENE

En gros, ces 3 articles disent que la dyslexie n'est pas qu'une question de déficience phonologique, mais bien un problème de mémoire à la base ou un multidéficit qui englobe la mémoire.

L'un parle de la mémoire à court terme, l'autre de la mémoire à long terme pour l'écrit mais aussi pour ce qui est visuel et visuospatial. Le troisième parle aussi de problèmes de mémoire procédurale non seulement pour l'écrit, mais aussi pour d'autres tâches et pointe un problème d'ancrage des apprentissages pendant le sommeil.

Cela fait tellement longtemps que les parents ont constaté ces problèmes chez leurs enfants ! Il est temps de trouver enfin des scientifiques qui s'y penchent !

J'ai demandé en 2000 un EEG pendant la nuit pour mon fils, car je soupçonnais déjà un problème d'ancrage des connaissances pendant le sommeil, donc de mémoire procédurale et de mémoire à court terme empêchant les données d'entrer dans la mémoire à long terme.

L'EEG n'a rien montré, la technique a ses limites pour déceler les problèmes... l'EEG ne peut montrer que les minis crises d'épilepsie indétectables autrement. Mais on sait bien qu'il n'y a pas que les crises d'épilepsies qui peuvent empêcher la mémorisation de se faire correctement.

Merci pour ces articles !

Merci beaucoup Claude.

Pour ma fille, pas besoin de passer un EEG pour savoir que son sommeil est de mauvaise qualité, il suffit de l'avoir entendu bouger et parler une bonne partie de la nuit. Sans parler de son impression de ne pas avoir dormi au reveil que je connais si bien.

La fatigabilité ou fatigue perpétuelle.

GENE