Cortical Areas Involved in Vertical Saccades With a 3 Teslas Functional Mri

Static postural control in children with developmental dyslexia

Correspondence to: Service d’Ophtalmologie, CHU de Dijon, 3 rue du Faubourg Raines, F-21000 Dijon, France. Tel.: +33 3 80 24 68 74; fax: +33 3 80 24 11 39.; International audience; The present investigation tries to better understand potential association and causal relationship between phonological and postural impairment due to developmental dyslexia. The study included 50 boys with developmental dyslexia and selected on the basis of their overall reading difficulties, and 42 control boys. Body sway during a quite standing posture eye open and eye closed on a force platform were tested in the two groups of subjects that were between 10 and 13 years of age. Analysis of classical parameters…

Left minineglect or inverse pseudoneglect in children with dyslexia?

International audience; This study compared the visuospatial asymmetries in children with dyslexia and healthy children by using the manual line bisection task, and investigated the processing of spatial context with a 'local' cueing paradigm consisting of geometric symbols placed on the extremities of the lines. The performance between healthy children (leftward bias) and children with dyslexia (rightward bias) was significantly different. Furthermore, the bisection mark was shifted in the direction of the unilaterally cued extremities in all children. As children with dyslexia showed a rightward bias in their spatial representation, which did not interfere with local context processing, w…

Children with Dyslexia Have Altered Cross-Modal Processing Linked to Binocular Fusion. A Pilot Study

Patrick Quercia, 1 Thierry Pozzo, 2 Alfredo Marino, 3 Anne Laure Guillemant, 1 Céline Cappe, 4 Nicolas Gueugneau 1 1Université de Bourgogne, Dijon, Campus Universitaire, UFR STAPS, BP 27877, F-21078 Dijon, France; INSERM U1093, Cognition, Action et Plasticité Sensorimotrice, Dijon F-21078, France; 2Center for Translational Neurophysiology, Istituto Italiano di Tecnologia, Ferrara, Italy; 3Private Consultant, Vicenza 36100, Italie; 4Brain and Cognition Research Center, CerCo, CNRS UMR 5549, Toulouse, FranceCorrespondence: Patrick QuerciaMedical Office, 15 Rue du Clair Matin, Beaune 21200, FranceTel +33 6 87822741Email doc.quercia@gmail.comIntroduction: The ca…

<p>Children with Dyslexia Have Altered Cross-Modal Processing Linked to Binocular Fusion. A Pilot Study</p>

Introduction The cause of dyslexia, a reading disability characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities, is unknown. A considerable body of evidence shows that dyslexics have phonological disorders. Other studies support a theory of altered cross-modal processing with the existence of a pan-sensory temporal processing deficit associated with dyslexia. Learning to read ultimately relies on the formation of automatic multisensory representations of sounds and their written representation while eyes fix a word or move along a text. We therefore studied the effect of brief sounds on vision with a modification of binocular f…

<p>Alteration in binocular fusion modifies audiovisual integration in children</p>

Background: In the field of multisensory integration, vision is generally thought to dominate audiovisual interactions, at least in spatial tasks, but the role of binocular fusion in audiovisual integration has not yet been studied. Methods: Using the Maddox test, a classical ophthalmological test used to subjectively detect a latent unilateral eye deviation, we checked whether an alteration in binocular vision in young patients would be able to change audiovisual integration. The study was performed on a group of ten children (five males and five females aged 11.3±1.6 years) with normal binocular vision, and revealed a visual phenomenon consisting of stochastic disappearanceof part of a vi…

Developmental dyslexia and vision

International audience; Developmental dyslexia affects almost 10% of school-aged children and represents a significant public health problem. Its etiology is unknown. The consistent presence of phonological difficulties combined with an inability to manipulate language sounds and the grapheme-phoneme conversion is widely acknowledged. Numerous scientific studies have also documented the presence of eye movement anomalies and deficits of perception of low contrast, low spatial frequency, and high frequency temporal visual information in dyslexics. Anomalies of visual attention with short visual attention spans have also been demonstrated in a large number of cases. Spatial orientation is als…

Cognitive demands impair postural control in developmental dyslexia: A negative effect that can be compensated

Children with developmental dyslexia exhibit delayed reading abilities and various sensori-motor deficits. The way these various symptoms interact remain poorly understood. The objective of this study was twofold. First, we aimed to investigate whether postural control was impaired in dyslexic children when cognitive demands are increased. Second, we checked whether this effect could be reduced significantly by a treatment aiming to recalibrate ocular proprioception. Twelve dyslexic and fifteen treated dyslexic children (>3 months of treatment) were compared with twelve non-dyslexic children in two conditions (mean age: 11.6 ± 2.1, 12.5 ± 1.5 and 10.6 ± 1.7 years respectively). In a first c…

Representational Bias in the Radial Axis in Children With Dyslexia: A Landmarks Alignment Study.

To better identify the distinctive characteristics of space representation in the radial dimension, we have proposed a new paradigm: the landmarks alignment task where two parallel aluminum bars were radially presented. Children had to move a landmark along one bar and place it at the same location as the reference landmark placed by the examiner on the parallel bar. The major interest of this task was its capacity to assess space representation in the radial dimension when considering a spatial landmark that oriented the subject’s attention toward the orthogonal dimension. The most important result showed that in the radial dimension children with dyslexia exhibited a forward bias on the …

Developmental dyslexia and vision

Patrick Quercia,1 Léonard Feiss,2 Carine Michel31Department of Ophthalmology, University Hospital, Dijon, France; 2Office of Ophthalmology, Beaune, France; 3University of Burgundy, Dijon, INSERM U1093, Cognition, Action et Plasticité Sensorimotrice, Dijon, FranceAbstract: Developmental dyslexia affects almost 10% of school-aged children and represents a significant public health problem. Its etiology is unknown. The consistent presence of phonological difficulties combined with an inability to manipulate language sounds and the grapheme–phoneme conversion is widely acknowledged. Numerous scientific studies have also documented the presence of eye movement ano…

Space representation in children with dyslexia and children without dyslexia: Contribution of line bisection and circle centering tasks

International audience; Line bisection tasks (different space locations and different line lengths) and circle centering tasks (visuo-proprioceptive and proprioceptive explorations, with left or right starting positions) were used to investigate space representation in children with dyslexia and children without dyslexia. In line bisection, children with dyslexia showed a significant rightward bias for central and right-sided locations and a leftward bias for left-sided location. Furthermore, the spatial context processing was asymmetrically more efficient in the left space. In children without dyslexia, no significant bias was observed in central lines but the spatial context processing wa…