Visual Attention, Reading & Dyslexia

Project Details

The basic cause of specific reading disability, commonly known as dyslexia, has been a matter of intense debate for decades.  Reading is a relatively recent activity in human history and so it is very unlikely that humans have evolved a specific brain region or circuitry devoted to reading.  As with so many modern developments, we probably use for reading a brain function that evolved for a different purpose. Our lab has been working on the idea that the critical brain function that is being recycled for reading is the visuo-spatial attention network usually used in visual search (such as finding a face in a crowd) and in focussing attention at a visual field location for object identification.  We have recently found the visual attention efficiency to differ substantially between people and it is related both to reading speeds and to the functional size of the primary visual cortex. At present, we are exploring these relationships further using visual psychophysics and functional brain imaging in the dyslexic population and also comparing reading of scripts written from left to right (as in English) with those written from right to left (as in Farsi).

Prof. Vidyasagar interviewed at University of Padova, Italy