A fejlődési diszlexia az olvasás elsajátításának zavara megfelelő életkori, intelligencia- és nevelési feltételek megléte mellett. Elméletei közül ismert a fonológiai sérülés; a gyors hallási feldolgozás feltevés; újabban a látási elmélet. A látási deficit származhat a bizonytalan binokuláris fixációból vagy pl. a gyenge konvergens/divergens szemmozgásból. A cerebelláris/automatizálódási feltevés szerint a diszlexiásoknál enyhe cerebellum sérülés van, amely különböző kognitív zavarokkal jár együtt. A magnocelluláris elmélet fő állítása, hogy az olvasási probléma nem nyelvi, hanem a vizuális/hallási magnocelluláris rendszer általános sérülésének következménye: csökkent a mozgásérzékenység és a kontrasztérzékenység.
Vizsgálatunkban a magnocelluláris sérülés feltevést, a koherens mozgásészlelés és a kontúrintegráció közötti kapcsolatot vizsgáltuk 61 fő gyengén olvasó és diszlexiás és 46 fő tipikusan fejlődő gyereknél. A koherens mozgásészlelés küszöbeit vizsgálva és kontúrintegrációs faladatban is szignifikáns különbségek mutatkoztak a gyengén olvasó (diszlexiás) és a kontrollcsoport között. További eredményünk szerint a gyengén olvasó (diszlexiás) csoportnál a koherens mozgásészlelési küszöb (összesített átlag) és a kontúr integrációs feladat teljesítménye korrelál, a tipikus fejlődésű, normál olvasási csoport esetében a korreláció nem szignifikáns.
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