Methods of investigating a visual deficit in dyslexia

The evidence for a visual deficit in dyslexia is inconclusive. We have developed several tests to investigate the parallel pathways of the visual system which can be applied to dyslexic subjects. Using the techniques of electroretinography, visual evoked potentials, adaptometry and contrast sensitivity, special protocols have been designed to elicit responses from these parallel pathways. These techniques are also applicable in the investigation of many pathological conditions, and of interest for pure research.