Purpose: As well as obtaining confirmation of the magnocellular system involvement in developmental dyslexia (DD); the aim was primarily to search for a possible involvement of the parvocellular system; and, furthermore, to complete the assessment of the visual chromatic axis by also analysing the koniocellular system. Methods: Visual evoked potentials (VEPs) in response to achromatic stimuli with low luminance contrast and low spatial frequency, and isoluminant red/green and blue/yellow stimuli with high spatial frequency were recorded in 10 dyslexic children and 10 age- and sex-matched, healthy subjects. Results: Dyslexic children showed delayed VEPs to both achromatic stimuli (magnocellular-dorsal stream) and isoluminant red/green and blue/yellow stimuli (parvocellular-ventral and koniocellular streams). To our knowledge, this is the first time that a dysfunction of colour vision has been brought to light in an objective way (i.e., by means of electrophysiological methods) in children with DD. Conclusion: These results give rise to speculation concerning the need for a putative approach for promoting both learning how to read and/or improving existing reading skills of children with or at risk of DD. The working hypothesis would be to combine two integrated interventions in a single programme aimed at fostering the function of both the magnocellular and the parvocellular streams.
Defective chromatic and achromatic visual pathways in developmental dyslexia : Cues for an integrated intervention programme / L. Bonfiglio, T. Bocci, F. Minichilli, A. Crecchi, D. Barloscio, D.M. Spina, B. Rossi, F. Sartucci. - In: RESTORATIVE NEUROLOGY AND NEUROSCIENCE. - ISSN 0922-6028. - 35:1(2017), pp. 11-24.
|Titolo:||Defective chromatic and achromatic visual pathways in developmental dyslexia : Cues for an integrated intervention programme|
BOCCI, TOMMASO (Secondo)
|Parole Chiave:||chromatic contrast; koniocellular; letter recognition; luminance contrast; magnocellular; parvocellular; Reading disorder; VEPs; Adolescent; Analysis of Variance; Child; Color Perception; Contrast Sensitivity; Dyslexia; Electroencephalography; Evoked Potentials, Visual; Female; Humans; Male; Photic Stimulation; Visual Pathways; Cues; Neurology; Developmental Neuroscience; Neurology (clinical)|
|Settore Scientifico Disciplinare:||Settore MED/26 - Neurologia|
|Data di pubblicazione:||2017|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.3233/RNN-160636|
|Appare nelle tipologie:||01 - Articolo su periodico|
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