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Disconnection syndrome is a general term for a number of neurological symptoms caused by damage to the white matter axons of communication pathways—via lesions to association fibers or commissural fibers—in the cerebrum, independent of any lesions to the cortex. The behavioral effects of such disconnections are relatively predictable in adults. Callosal syndrome, or split-brain, is an example of a disconnection syndrome from damage to the corpus callosum between the two hemispheres of the brain. Disconnection syndrome can also lead to aphasia, left-sided apraxia, and tactile aphasia, among other symptoms. ==History== The concept of disconnection syndrome emerged in the late nineteenth century when scientists became aware that certain neurological disorders result from communication problems among brain areas. In 1874, Carl Wernicke introduced this concept in his dissertation when he suggested that conduction aphasia could result from the disconnection of the sensory speech zone from the motor speech area by a single lesion in the left hemisphere〔 to the arcuate fasciculus. Lissauer, a pupil of Wernicke, described a case of visual agnosia as a disconnection between the visual and language areas. Dejerine in 1892 described specific symptoms resulting from a lesion to the corpus callosum that caused alexia without agraphia. The patient had a lesion in the left occipital lobe, blocking sight in the right visual field (hemianopia), and in the splenium of the corpus callosum. Dejerine interpreted this case as a disconnection of the speech area in the left hemisphere from the right visual cortex. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Disconnection syndrome」の詳細全文を読む スポンサード リンク
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