Is there a visual dyslexia.

Traditionally, it has been speculated that weaknesses in the visual processing of cognitive aspects of the written word could lead to reading problems, and if so, such a condition would constitute a subtype of developmental dyslexia. This putative subtype has been referred to as visual dyslexia. In this article, the role of cognitive deficits that are visual in nature as a potential etiological factor of developmental dyslexia is examined. Following a brief history of the study of dyslexia, a critique of studies of visual dyslexia is presented. Subsequently, the nature of the visual processes involved in word- recognition is examined. Finally, three research studies that assessed the contribution of visual memory to word-recognition are presented. It is concluded that, even though defects in the physiological aspects of visual processing can lead to reading difficulties, at present little convincing evidence is available to conclude that a subtype of dyslexia caused by cognitive deficits associated with visual processing of information exists.