Developmental dyslexia: Four consecutive patients with cortical anomalies

TLDR

The study discusses how developmental cortical anomalies, cerebral asymmetries, brain reorganization after early lesions, and links between learning disorders, left‑handedness, and immune diseases relate to the findings. The authors report neuroanatomical findings from four consecutively studied dyslexic male brains. The four patients, aged 14–32, were diagnosed with dyslexia in life and had histories of non‑right‑handedness, autoimmune, and atopic conditions. All brains exhibited cortical developmental anomalies, including neuronal ectopias and architectonic dysplasias mainly in perisylvian left‑hemisphere regions, and displayed symmetrical planum temporale, deviating from typical asymmetry.

Abstract

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.