Distribution of degenerated fibers in the cortex of the medial and lateral surfaces of the dog's brain after destruction of the anterior limbic and motor areas

Summary Damage to the anterior limbic and motor regions of the brain cortex results in two types of distribution of degenerated fibers over the brain cortex in dogs. The first lateral type is characterized by a predominant fragmentation of a large number of thick horizontal or diagonal fibers of the lower cortical layers on the lateral surface; the second type, known as medial, by the fragmentation of single slender radial fibers and horizontal fibers of the first cortical layer on the medial surface.The lateral-type degenerated fibers are distributed over the cortex of the sigmoid, presplenial, suprasplenial and ectolateral convolutions (motor, parietal and occipital fields). They are most numerous in the motor (4) and optic (19, 18) areas. The medial-type degeneration is characteristic of the cingulum (gyrus cinguli) (limbic fields).An injury to the anterior and posterior portions of the sigmoid convolution causes a less extensive lateral-type degeneration than an injury to the genual convolution.Presented by Academician V. N. Chernigovskii Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 59, No. 3, pp. 18–22, March, 1965