Developmental dyslexia: Four consecutive patients with cortical anomalies

Authors

  • Dr. Albert M. Galaburda MD,

    Corresponding author
    1. Dyslexia Research Laboratory and the Charles A. Dana Research Institute, Beth Israel Hospital, and the Department of Neurology, Beth Israel Hospital and Harvard Medical School, 330 Brookline Ave, Boston, MA 02215
    • Dyslexia Research Laboratory and the Charles A. Dana Research Institute, Beth Israel Hospital, and the Department of Neurology, Beth Israel Hospital and Harvard Medical School, 330 Brookline Ave, Boston, MA 02215
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  • Gordon F. Sherman PhD,

    1. Dyslexia Research Laboratory and the Charles A. Dana Research Institute, Beth Israel Hospital, and the Department of Neurology, Beth Israel Hospital and Harvard Medical School, 330 Brookline Ave, Boston, MA 02215
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  • Glenn D. Rosen PhD,

    1. Dyslexia Research Laboratory and the Charles A. Dana Research Institute, Beth Israel Hospital, and the Department of Neurology, Beth Israel Hospital and Harvard Medical School, 330 Brookline Ave, Boston, MA 02215
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  • Francisco Aboitiz MBiol,

    1. Dyslexia Research Laboratory and the Charles A. Dana Research Institute, Beth Israel Hospital, and the Department of Neurology, Beth Israel Hospital and Harvard Medical School, 330 Brookline Ave, Boston, MA 02215
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  • Norman Geschwind MD

    1. Dyslexia Research Laboratory and the Charles A. Dana Research Institute, Beth Israel Hospital, and the Department of Neurology, Beth Israel Hospital and Harvard Medical School, 330 Brookline Ave, Boston, MA 02215
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Abstract

We report the neuroanatomical findings in 4 consecutively studied brains of men with developmental dyslexia. The patients, who ranged in age between 14 and 32 years, were diagnosed as dyslexic during life. Nonrighthandedness and several autoimmune and atopic illnesses were present in the personal and family histories. All brains showed developmental anomalies of the cerebral cortex. These consisted of neuronal ectopias and architectonic dysplasias located mainly in perisylvian regions and affecting predominantly the left hemisphere. Furthermore, all brains showed a deviation from the standard pattern of cerebral asymmetry characterized by symmetry of the planum temporale. The neuroanatomical findings in these 4 patients are discussed with reference to developmental cortical anomalies, cerebral asymmetries, reorganization of the brain after early lesions, and the association between learning disorders, left handedness, and diseases of the immune system.

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