THE FORGOTTEN LESSON OF MONSIEUR C
READING has been an important skill in Western society for many hundreds of years. Yet even at a time when universal literacy is at a premium, a significant number of people seem to have serious difficulties learning to read. Furthermore, a smaller number, perhaps 3 percent of the population, find themselves unable to read at all. Some are educationally deprived or have emotional blocks; others are mentally retarded or brain-damaged. But some nonreaders are of normal or high intelligence, have gone to the best schools, and appear free of personal problems, retardation, and brain damage. They seem blind to words as some people are blind to colors. They exhibit a syndrome that has been called developmental dyslexia.
There is considerable disagreement among those who study reading problems about what causes dyslexia and how it should be treated. Psychologists interested in personality development often invoke a motivational explanation, while those who study cognitive processes may attribute dyslexia to perceptual or learning disorders. I believe that a clue central to the mystery of dyslexia was uncovered in France nearly a century ago.
In October 1887 Monsieur C, a wealthy businessman in his late sixties, experienced several attacks of numbness in his right leg, some feebleness in his arms, and a little trouble speaking. When his symptoms