THE word “dyslexia” evokes painful struggles with reading, and indeed this learning disability causes much difficulty for the estimated 15 percent of Americans affected by it. Since the phenomenon of “word blindness” was first documented more than a century ago, scientists have searched for the causes of dyslexia, and for therapies to treat it. In recent years, however, dyslexia research has taken a surprising turn: identifying the ways in which people with dyslexia have skills that are superior to those of typical readers. The latest findings on dyslexia are leading to a new way of looking at the condition: not just as an impediment, but as an advantage, especially in certain artistic and scientific fields.
Dyslexia is a complex disorder, and there is much that is still not understood about it. But a series of ingenious experiments have shown that many people with dyslexia possess distinctive perceptual abilities. For example, scientists have produced a growing body of evidence that people with the condition have sharper peripheral vision than others. Gadi Geiger and Jerome Lettvin, cognitive scientists at the Massachusetts Institute of Technology, used a mechanical shutter, called a tachistoscope, to briefly flash a row of letters extending from the center of a subject’s field of vision out to its perimeter. Typical readers identified the letters in the middle of the row with greater accuracy. Those with dyslexia triumphed, however, when asked to identify letters located in the row’s outer reaches.
Mr. Geiger and Mr. Lettvin’s findings, which have been confirmed in several subsequent studies, provide a striking demonstration of the fact that the brain separately processes information that streams from the central and the peripheral areas of the visual field. Moreover, these capacities appear to trade off: if you’re adept at focusing on details located in the center of the visual field, which is key to reading, you’re likely to be less proficient at recognizing features and patterns in the broad regions of the periphery.
The opposite is also the case. People with dyslexia, who have a bias in favor of the visual periphery, can rapidly take in a scene as a whole — what researchers call absorbing the “visual gist.”