Journal article

Dyslexia: a deficit in visuo-spatial attention, not in phonological processing

Trichur R Vidyasagar, Kristen Pammer

Trends in Cognitive Sciences | ELSEVIER SCIENCE LONDON | Published : 2010


Developmental dyslexia affects up to 10 per cent of the population and it is important to understand its causes. It is widely assumed that phonological deficits, that is, deficits in how words are sounded out, cause the reading difficulties in dyslexia. However, there is emerging evidence that phonological problems and the reading impairment both arise from poor visual (i.e., orthographic) coding. We argue that attentional mechanisms controlled by the dorsal visual stream help in serial scanning of letters and any deficits in this process will cause a cascade of effects, including impairments in visual processing of graphemes, their translation into phonemes and the development of phonemic a..

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