Disabled readers suffer from visual and auditory impairments but not from a specific magnocellular deficit

S. Amitay
2002 Brain  
that some RD subjects (six out of 30) had impaired magnocellular function. Nevertheless, these RD subjects were also consistently impaired on a broad range of other perceptual tasks. The performance of the other subgroup of RD subjects on magnocellular tasks did not differ from that of controls. However, they did show impaired performance in both visual and auditory nonmagnocellular tasks requiring ®ne frequency discriminations. The stimuli used in these tasks were neither modulated in time nor
more » ... brie¯y presented. We conclude that some RD subjects have generally impaired perceptual skills. Many RD subjects have more speci®c perceptual de®cits; however, the'magnocellular' level of description did not capture the nature of the perceptual dif®culties in any of the RD individuals assessed by us. Abbreviations: 2AFC = two-alternative forced choice; ISI = inter-stimulus interval; JND = just-noticeable difference; LGN = lateral geniculate nucleus; MT = medial temporal area; RD = reading disabled; RDK = random dot kinematogram; SPL = sound pressure level; V1 = primary visual cortex ã
doi:10.1093/brain/awf231 pmid:12244084 fatcat:gzkghc4hsjdczntbxuai26atwi