The main aim of this paper was to review different hypotheses which have related dyslexia with a deficit in visual perception, namely: the lack of eye dominance; problems in parafoveal vision; deficit in oculomotor control; deficits in early stages of visual processing and magnocellular pathway dysfunctions. It is concluded that there is sufficient evidence to justify the conclusion about the existence of a perceptual dysfunction linked to the etiology of dyslexia. However, it would be necessary to explain how this deficit affects only reading and not other activities in the dyslexic’s everyday life. Finally, we discuss the possible existence of different subtypes of developmental dyslexia and how this could explain the controversy in the results of the investigations about the dyslexia etiology.
