Paralysis of an extremity or of part of one extremity may occur from a limited lesion of the cortex. Lesions of the internal capsule when present produce a more extensive paralysis, and it is almost inconceivable that a monoplegia or a segmental monoplegia could arise from a lesion anywhere in the cerebrum except in the cortex. Limited lesions of the cortex secondary to vascular disease may be so small as to produce aphasia, either motor or sensory, alexia, the parietal lobe syndrome or hemianopia, but it is unusual for a patient to have a monoplegia or a segmental monoplegia due to a vascular lesion; when such a condition exists it is perhaps more frequently seen in the upper than in the lower extremities.
Paralysis of one extremity or of a limited portion of one extremity is frequently seen in cerebral neoplasms, and was not uncommon during the late war in