Diagnostic and rehabilitation of cognitive deficiencies in dyslexic children
Contact person
Nathalie BEDOIN , Christophe DOS SANTOS , Sonia KRIFI , Egidio MARSICO , Francois PELLEGRINO
Scientific framework and objectives
Reading is an activity of central concern in our society. However, dyslexic children are presenting with important, specific and persistent difficulties in learning to read. Numerous cognitive processes are involved in reading and many kinds of cognitive deficits can result in various forms of dyslexia. We investigate cases of dyslexic children suffering from important phonological deficiencies, but also children with surface dyslexia, who present with visual attentional deficiencies. Our purpose is to describe more precisely what cognitive mechanisms are impaired in visual attentional processes; we assume that some children with surface dyslexia suffer from major difficulties in inhibiting non relevant information from details (local level information) and in focusing on the global aspect of complex visual scenes. Similarly, regarding phonological deficiencies, we assess disorders in phonological representations at a detailed level (i.e., sub-phonemic level). This research uses the results of our previous studies conducted with adult good readers and children without learning deficiency, about global/local processing of visual information and sub-phonemic similarity effects in reading.
We aim at providing new tools to assess more precisely what kind of cognitive deficiencies dyslexic young patients do suffer from, and new rehabilitation training programmes intended to improve the phonological organisation of knowledge and/or the efficiency of subtle visual attentional mechanisms. This material is designed to be used by speech therapists or neuropsychologists.
Priming and masking experiments provided evidence for the involvement of sub-phonemic knowledge in print processing. For instance, the respective sonority indices of the consonants displayed at the frontier of syllables within a word do affect the speed and accuracy of syllable identification (Bedoin & Dissard, 2002 ; Fabre & Bedoin, 2003). Additionally, the identification of a consonant in a printed word is influenced by its phonetic similarity with other consonants of the word. Therefore, in a C1VC2V printed word, the identification of C2 is impaired if C2 shares phonetic features with C1, whereas such a sub-phonemic similarity improves the identification of C1. In order to account for these effects in reading, we have proposed a model for the cognitive organisation of phoneme-units, based on lateral inhibitory connections between phoneme-units, the weight of which is assumed to be dependent on the amount of shared phonetic features (Bedoin, 2003). Sub-phonemic similarity effects are complex and vary with the phonetic feature category (voicing, place or manner of articulation); we investigate the hierarchical organisation of these phonetic features in reading (Bedoin & Krifi, to appear). Lateral inhibitory relations may help the reader to escape from errors due to progressive harmony phenomenon, which result in reading mistakes. The elaboration of lateral inhibitory relations between phoneme detectors is assumed to efficiently counter such errors (Bedoin & Dos Santos, 2008). Experiments conducted with children showed that sub-phonemic similarity effects are associated with successful learning to read: such effects are significant in third graders, but they are not observed in second graders, nor in dyslexic children (Krifi, Bedoin, & Mérigot, 2003). After an intensive audio-visual training designed to implicitly attract attention by sub-phonemic aspects, dyslexic children presented with the same pattern of sub-phonemic effects as it was observed in good readers (Bedoin, 2003). After this training programme, the performances that they exhibited for letter identification within a word could be explained by the involvement of between-phoneme inhibitory connections, as in skilled readers. Other drills designed to lead children to improve the organisation of sub-phonemic knowledge (phonetic features, sonority indices) are proposed to dyslexic children presenting with phonological deficiencies.
Additionally, we elaborated a new test (FocalDivi) aimed at detecting two kinds of deficits: one of them is observed in dyslexic children suffering from phonological deficiencies, while the other one has only been evidenced in children with surface dyslexia. In this task, the participant is invited to focus attention either to the global (during one block of stimuli) or the local level (another block) of letter-based or object-based hierarchical stimuli. We use rapid half-field presentation to assess the respective involvement of right and left hemispheres. Using this test, we detected atypical hemispheric lateralisation effects associated with the stimulus category in dyslexic children suffering from phonological deficiencies (they presented with a left hemisphere advantage associated not only with letter processing, but also with objects processing). Children with surface dyslexia did not present with such atypical hemispheric lateralisation effects, but they had specific difficulties to inhibit information from the local level, while they tried to focus on the global level. This deficiency occurred whatever the category of the hierarchical stimulus, which suggests the visual-attentional nature of the problem. FocalDivi test seems to provide knew insights in the diagnosis of cognitive deficiencies in dyslexic children, which may help to guide towards more relevant rehabilitation programmes. One training programme designed to improve the efficiency to inhibit local information and focus on the global aspect of complex visual scenes has been elaborated and proposed to 5 children with surface dyslexia. After training, these specific abilities improved, and children managed to simultaneously process a greater number of letters. Additionally, their performances increased in reading and writing words, especially irregular ones (Bedoin et al., 2007).
Financial support
- Cluster 11, Vieillissement, handicap, neuroscience (Action n° 3 : Audition, Vision, Langage
Children with deficits in learning to read: Prevention, diagnosis, and rehabilitation Région Rhône-Alpes 2006-2008
Publications
- Bedoin, N., 1992, "Etude de l'articulation de différentes procédures mentales dans les activités sémantiques : exemples de la lecture et de la catégorisation", Nouveau Régime, Psychologie, Université Lyon 2, Lyon, 763 p.
- Bedoin, N., 1995, "Articulation de codages phonologiques et sémantiques en lecture silencieuse : étude du décours temporel des codes phonologiques", Revue de Phonétique Appliquée, 115, pp. 101-118
- Bedoin, N., 2003, "Sensitivity to voicing similarity in printed stimuli: Effect of a training programme in dyslexic children", Journal of Phonetics, 31:3-4, pp. 541-546
- Bedoin, N., Dissard, P., 2002, "Sonority and syllabic structure in reading: Differences between French and English readers", Current Psychology Letters: Behaviour, Brain & Cognition, 2:8, pp. 67-83
- Bedoin, N., Siéroff, E., 1989, "Activation phonologique dans la lecture : comparaison de deux tâches", Cahiers de Psychologie Cognitive: EUropean Bulletin of Cognitive Psychology, 9:5, pp. 545-560
- Bedoin, N., Koenig, O., 1997, "La compréhension du langage par modèles sous-jacents. ", in Sciences cognitives : diversité des approches. , Gordon, M., Paugam-Moisy, H. (eds), Hermès, Paris, Hermès, pp. 115-123
- Bedoin, N., Siéroff, E., 1990, "Rôle des tâches et des stratégies dans l'activation phonologique en lecture. ", in Informatique et différences individuelles. , Martin, R. (eds), Presses Universitaires de Lyon, Lyon, Presses Universitaires de Lyon, pp. 249-254
- Bedoin, N., 1998, "Les traits phonétiques en lecture silencieuse", actes de 2èmes Journées Scientifiques de l'Ecole d'Orthophonie de Lyon : à propos de la conscience phonologique, Lyon, novembre 1998
- Bedoin, N., 2002, "Relationships between temporal aspects of speech perception and dyslexia", proc. of Temporal Integration in Perception of Speech (TIPS), ISCA International Tutorial and Research Workshop, Aix en Provence, avril 2002
- Bedoin, N., 2005, "The hierarchy of phonetic features categories in printed syllables matching in adult skilled readers, normally developing young readers, and dyslexic children", proc. of Workshop Phonological systems and complex adaptive systems , Lyon, Juillet 2005
- Bedoin, N., 1997, "Activations phonétiques dans le processus de reconnaissance de mots écrits : amorçage et backward masking", Séminaire de Psychologie Cognitive, Université Lyon 2, janvier 1997
- Bedoin, N., 2000, "Psychologie cognitive, psycholinguistique et développement de l'enfant", Journées "L'Enfant Créatif", Mairie de Vénissieux, novembre 2000
- Bedoin, N., 2001, "Traitement des traits phonétiques chez les enfants bons lecteurs et les enfants dyslexiques", Réunions de Neuropédiatrie, Hôpital Lyon-Sud, Lyon, mars 2001
- Bedoin, N., 2004, "Attention visuo-spatiale et dominance hémisphérique dans le traitement de lettres et de dessins hiérarchisés : développement normal et dyslexie développementale", Séminaire du Laboratoire Psychologie et Neurocognition (LPNC), Université de Grenoble 2, mai 2004
- Bedoin, N., 2005, "Troubles cognitifs en dyslexie développementale : déficits phonologiques et visuo-attentionnels. Usages sociaux des recherches en cours", Séminaire de l'Institut d'Etudes Politiques de Lyon, Université Lyon 2, mars 2005
- Bedoin, N., 2006, "Utilisation des stimuli hiérarchisés en recherche fondamentale et approche clinique", Séminaire de Neuropsychologie "Fan's Club de Neuropsychologie" de Lyon, Hôpital Debrousse, Lyon, mars 2006
- Bedoin, N., 2007, "Anomalies de l'organisation des connaissances sur les traits phonétiques et troubles visuo-attentionnels : dépistage et tentatives de remédiation autour de deux déficits cognitifs chez des enfants dyslexiques", Séminaire du Laboratoire ACCOLADE, Université de Reims, février 2007
- Bedoin, N., 1990, "Représentation des propriétés des objets et activité sémantique dans la lecture : vers le concept de spécicalité", actes de Congrès Annuel "La Lecture : Processus, Apprentissages, Evoluation, Troubles", Société Française de Psychologie, Lille, France, 1990
- Bedoin, N., 1994, "Phonological and semantic codes and word recognition in reading", proc. of 23rd International Congress of Applied Psychology, Madrid, Spain, Juillet 1994
- Bedoin, N., 1998, "Phonological feature activation in visual word recognition", proc. of 10th Conference of the European Society for Cognitive Psychology (ESCOP 10), Jerusalem, Israël, Septembre 1998
- Bedoin, N., Chavand, H., 2000, "Functional hemispheric asymmetry in voicing feature processing in reading", proc. of 10th Annual Meeting of the Society for Text ans Discourse, Lyon, July, 2000, pp. 226-227
- Bedoin, N., Dissard, P., 2001, "Intra-syllabic structure and sonority of consonants in printed stimuli: Differences between French and ENglish readers", proc. of 12th Conference of the European Society for Cognitive Psychology, Edinburgh, Scotland, 2001, September
- Bedoin, N., Dworczak, F., Krifi, S., 2003, "Developmental Dyslexia: Phonological and visuo-spatial disorders", proc. of 8th Congrès Biannuel de la Société Latinoaméricaine de Neuropsychologie (SLAN), Montreal, 2003, October
- Bedoin, N., Dworczak, F., Laffont, M., Krifi, S., Nazir, T., Michalon, S., 2003, "Nouvelles technologies de l'information et dyslexie chez l'enfant : vers une amélioration des relations entre les personnes concernées (milieux médiacal, scolaire, familial)", proc. of Symposium on New Research Trends in Higher Brain Functions and their Pharmacology: From Molecular to Cognitive Levels, Ajaccio, France, 2003
- Bedoin, N., Siéroff, E., 1989, "Activation phonologique et attention dans la lecture : comparaison de plusieurs tâches", proc. of Colloque International des 8èmes Journées de Psychologie Différentielle, "Psychologie et Informatique", Lyon, 1989, Septembre
- Bedoin, N., 1993, "Place de la phonologie dans l'amorçage sémantique", actes de Colloque de l'APSLF "Universel et Différentiel", AIx-en-Provence, France, 1993
- Bedoin, N., 1994, "Codages phonologique et sémantique dans les premirèes étapes de traitement d'un mot écrit", proc. of 10ème Coloque International SGAV, "Parcours d'Acquisition du Langage : Psychologie et Didactique", Poitiers, France, 1994, Revue de Phonétique Appliquée, 115, pp. 101-118
- Bedoin, N., dos Santos, C., 2008, "Sub-phonemic influence of voicing feature in a reading task", proc. of The role of phonology in reading acquisition, Workshop at the 30th Annual Meeting of the Deutsche Gesellschaft für
Sprachwissenschaft (DGfS), Bamberg (Germany), february 28th 2008
- Bedoin, N., Roussel, C., Leculier, L., Krifi, S., Herbillon, V., 2007, "Effets d’un entraînement visuo-attentionnel chez des enfants dyslexiques de surface", actes de 3ème Journée Scientifique du Centre de Référence du CHU de Lyon pour les Troubles des Apprentissages de l’Enfant , Lyon, 12 octobre
- Bedoin, N., 2008, "Connaissances infra-phonémiques en lecture : lecture normale et dyslexies développementales", proc. of Colloque International « Conceptions naïves », Reims, France, janvier 2008
- Bedoin, N., Krifi, S., 2008, "Position des syllabes et effets de ressemblance infra-phonémique en lecture", actes de Société Française de Psychologie (SFP), Symposium Le rôle de la syllabe dans la lecture en français chez le lecteur apprenant et le lecteur expert , Bordeaux, France, septembre 2008
- Boudia, B., Koenig, O., Bedoin, N., Collet, L., 1999, "Phonological representations in postlingual deaf subjects using a multichannel cochlear implant", International Journal of Pediatric Otorhinolaryngology, 47, pp. 157-164
- Boudia, B., Koenig, O., Bedoin, N., Collet, L., 1996, "Phonological representations in postlingually deaf subjects using a multichannel cochlear implant", proc. of International Conference on Language Development in Cochlear Implanted Children, Lyon, 1996
- Boudia, B., Bedoin, N., Koenig, O., 1996, "Etude des représentations phonologiques chez l'adulte implanté cochléaire", Colloque "Perception, Cognition, Handicap", Lyon, 1996
- Chavand, H., Bedoin, N., 1998, "Phonetic features activation in visual word recognition: The case of the articulation point and the articulation manner", proc. of 10th Conference of the European Society for Cognitive Psychology, Jerusalem, Israel, 1998, September
- Chavand, H., Bedoin, N., 1998, "Différences hémisphériques dans le traitement des catégories de traits phonétiques en lecture", Colloque "Journée Lexique", Lyon, France, 1998, november
- Dissard, P., Bedoin, N., 1994, "Use of analogy in phoneme monitoring in a cross-modal condition: Arguments for interactive models", proc. of 23rd International Congress of Applied Psychology, Madrid, Spain, 1994, July
- Dissard, P., Bedoin, N., 1993, "Rôle de l'analogie et des traitements phonologiques dans la reconnaissance de mot", actes de Congrès de la Société Française de Psychologie (SFP), Poitiers, France, 1993
- Dworczak, F., Bedoin, N., Krifi, S., 2008, "Internet et troubles d'apprentissage : les synergies et partenariats créés", in Construire une communauté éducative : le partenariat familles - associations - écoles - universités, Pithon, G., Asdih, S., Larivée, C. (eds), Bruxelles, De Boeck, Perspectives en éducation et formation
- Dworczak, F., Krifi, S., Michalon, S., Bedoin, N., Nazir, T., Laffont, M., 2004, "The contribution of new technologies in the information and communication regarding the developmental dyslexia area", proc. of 4th Forum of European Neuroscience, Federation of European Neuroscience Societies (FENS), Lisbonne, Portugal, 2004, July
- Dworczak, F., Krifi, S., Michalon, S., Bedoin, N., Nazir, T., Lafont, M., 2004, "The contribution of new technologies in diagnosis and neuroremediation regarding dyslexia and attention deficit", proc. of 2rd International Congress on Neuroregeneration, Rio de Janeiro, Brazil, 2004, September
- Dworczak, F., Laffont, M., Krifi, S., Bedoin, N., Kéïta, L., Michalon, S., Nazir, T., 2005, "Troubles du langage et des apprentissages chez l'enfant : vers une amélioration des relations entre les milieux concernés", Congrès "Bilan Neuropsychologique", Caluire, France, 2005, March
- Fabre, D., Bedoin, N., 2003, "Sensitivity to sonority for print processing in normal readers and dyslexic children", Current Psychology Letters: Behaviour, Brain & Cognition, 10:1, pp. 1-6
- Fabre, D., Bedoin, N., 2003, "Sensitivity to sonority effects in reading: Illusory conjunction effects", proc. of 13th Conference of the European Society for Cognitive Psychology (ESCOP 13), Granada, Spain, 2003, September
- Fabre, D., Bedoin, N., 2002, "Sensibilité à la sonorité en lecture : normo-lecteurs et dyslexiques", actes de Journées "Trouble d'Apprentissage du Langage Oral ou Ecrit", Aix-en-Provence, France, 2002, November
- Kéïta, L., Bedoin, N., 2003, "Hierarchical stimuli processing and domain specific effect", proc. of 13th Conference of the European Society for Cognitive Psychology (ESCOP 13), Granada, Spain, 2003, September
- Kéïta, L., Bedoin, N., Herbillon, V., Lévy-Sebbag, H., Mérigot, A., 2005, "VIsual attention deficits and linguistic impairments in normal readers and dyslexic children", proc. of 17th European Academy of Childhood Disability Congress, Monaco, 2005, November
- Kéïta, L., Bedoin, N., Mérigot, A., Herbillon, V., 2005, "Global/local processing of letter-based and object-based hierarchical stimuli: A developmental and neuropsychological study", proc. of 14th Conference of the European Society for Cognitive Psychology, Leiden, Holland, 2005, September
- Kéïta, L., Bedoin, N., 2003, "Effets de contexte et latéralisation hémisphérique des traitements visuels de stimuli hiérarchisés", actes de Colloque des Jeunes Chercheurs en Sciences Cognitives, Paris, France, 2003, pp. 97-103
- Krifi, S., Bedoin, N., Mérigot, A., 2003, "Effects of voicing similarity between consonants in printed stimuli, in normal and dyslexic children", Current Psychology Letters: Behaviour, Brain & Cognition, 10:1, pp. 1-7
- Krifi, S., Bedoin, N., Herbillon, V., 2003, "Phonetic priming and backward masking in printed stimuli: A better understanding of normal reading and dyslexia", proc. of 13th Conference of the European Society for Cognitive Psychology (ESCOP 13), Granada, Spain, 2003, September
- Krifi, S., Bedoin, N., Herbillon, V., 2005, "The hierarchy of phonetic features categories in printed syllable matching: Normal reading and developmental dyslexia", proc. of 14th Conference of the European Society for Cognitive Psychology (ESCOP 14), Leiden, Holland, 2005, September
- Krifi, S., Bedoin, N., Herbillon, V., 2005, "Phonetic criteria and printed syllables matching in normal readers and dyslexic children", proc. of 17th European Academy of Childhood Disability Congress, Monaco, 2005, November
- Krifi, S., Bedoin, N., 2005, "Rôle de trois catégories de traits phonétiques dans l'appariement de syllabes écrites : lecture normale et dyslexie développementale", actes de Colloque "Un Siècle de Phonétique Expérimentale : Histoire et Développement", Grenoble, France, 2005, February
- Krifi, S., Bedoin, N., Herbillon, V., 2005, "Premiers pas vers un outil de remédiation pour enfants dyslexiques : appariement de syllabes et lecture", 4èmes Journées d'Etude et de Formation : Bilan Neuropsychologique et Démarches Pédagogiques, Caluire, France, 2005, March
- Krifi, S., Mérigot, A., Bedoin, N., 2002, "Traitement de la ressemblance de voisement en lecture et dyslexie", actes de Journées "Trouble d'Apprentissage du Langage Oral et Ecrit", Aix-en-Provence, France, 2002, November, Current Psychology Letters, 10, pp. 1-7
- Krifi, S., Bedoin, N., Herbillon, V., 2007, "Modèle d’organisation des connaissances sur les phonèmes : une explication des erreurs de lecture et d’écriture des enfants dyslexiques", actes de 3ème Journée Scientifique du Centre de Référence du CHU de Lyon pour les Troubles des Apprentissages de l’Enfant , Lyon (ENS Sciences), 12 octobre
- Paire-Ficout, L., Bedoin, N., 1996, "Code phonologique précoce et lisibilité labiale des mots chez le lecteur entendant et le lecteur sourd profond pré-lingual", Revue de Neuropsychologie, 6:2, pp. 239-250
- Paire-Ficout, L., Bedoin, N., 1996, "Différences temporelles dans l'intervention d'un code phonologique précoce en lecture chez les entendants et les sourds", proc. of 26th International Congress of Psychology, Montreal, 1996
- Paire-Ficout, L., Bedoin, N., Magnan, A., Ecalle, J., Brun, I., 2001, ""Lipreadability" and syllable structure complexity in deaf and hearing children: Effects in reading and writing tasks", proc. of 12th Conference of the European Society for Cognitive Psychology (ESCOP 12), Edinburgh, Scotland, 2001, September
- Paire-Ficout, L., Bedoin, N., 1994, "Comparaison d'un code phonologique précoce chez le lecteur entendant et le lecteur sourd profond pré-lingual", actes de Congrès de la Société Française de Psychologie (SFP), Montpellier, France, 1994
- Paire-Ficout, L., Bedoin, N., 1996, "Rôle du code phonologique précoce en lecture silencieuse chez des sourds et des entendants", Colloque "Perception, Cognition, Handicap", Lyon, France, 1996
- Paire-Ficout, L., Bedoin, N., 1996, "Les mécanismes de lecture chez les sourds", actes de Handica 96, Lyon, France, 1996
- Paire-Ficout, L., Bedoin, N., 1995, "Ressemblances et spécificité des mécanismes de lecture chez des sourds et des entendants", Sciences en Fête, Lyon, France, 1995
- Rebattel, M., Bedoin, N., 2001, "Cerebral hemipsheric asymmetry in voicing and manner of articulation processing in reading", proc. of 12th Conference of the European Society for Cognitive Psychology (Escop 12), Edinburgh, Scotland, 2001, September
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