133 Year History of the Anatomical Studies of Dyslexic Brains

1861 - Broca The language areas are located in the Left Hemisphere.

1874 - Wernicke Pin-pointed area, in and around the Sylvian Fissure.

1892 - Dejerine Damage to Left Angular Gyrus (sm. area in Posterior Neocortex) resulted in reading difficulties.

1896 - Morgan Dyslexia is a structural alteration of the Angular Gyrus.

1925 - Orton Dyslexia is caused by incomplete dominance of the language specialized Left Hemisphere over the Right Hemisphere.

1968 - Drake Microscopic examination of dyslexic brains finds: Large number of small gyri and a thin Corpus Callosum. Cortex was larger than normal with ectopic (out of place) neurons in subcortial white matter which usually contains only nerve fibers, not nerve cell bodies.

1978 - Rawson During gestation, dyslexic brain anomalies affect the organization of the brain (especially in the Right Hemisphere) resulting in the superior talents and abilities characteristic of people with dyslexia.

1980 - Gordon Dyslexics & their families did better than average on Right Hemisphere tasks: (model orientation, form completion, & block design), but below average on Left Hemisphere tasks: (serial sounds, circles, word production, digit span, and numbers.)

1982 - 1984 Left-handed families are 10X more likely than Girshwind/Behan right-handed families to have learning disabilities, autoimmune disorders (like allergies), skeletal mal- formations, thyroid disorders and migraine headaches.

1979 - 1985 Autopsies of 8 dyslexic brains found: A.) Unusual Galaburda bilateral symmetry in 15% of the brains; B.) Between 30-100 abnormalities per brain; C.) Abnormalities were located primarily in the Left Hemisphere, in clusters, and in the Sylvian Fissure area; D.) Abnormally small & poorly laminated folds and convolutions; E.) Abnormal neuron accumulations,and ectopias (clusters of neurons in the wrong place); F.) Distorted surface and disorganized subsurface neurological organization; G.) In females, neuronal loss and myelinated scars were apparent.

1988 - 1989 Phonological & syntactic uncertainty are the result of Bever/Sherman abnormally organized language regions with alterations in size, shape and organization of neurons; and abnormal location of cell tissue in an abnormally formed symmetrical brain (Right and Left Hemispheres being equal in size, vs. the normally occurring larger Left Hemisphere.)

1988 - Sherman Right brain lesions produce visual-spatial, and musical disabilities.

1994 - Wood Studies live dyslexics. 10% of the population has dyslexic brain waves.