[The influence of strabismus and monocular deprivation on the size of callosal cells in cortical areas 17 and 18 of the cat].

To reveal the changes in visual cortex structure following impaired early binocular experience, the size (somatic area) of callosal cells in areas 17, 18 ofmonocularly deprived and convergent strabismic cats was measured. Horseradish peroxidase was injected into the single ocular dominance columns of areas 17, 18 and the transition zone 17/18. In both groups of impaired cats the mean size of callosal cells in area 17 was increased in comparison to intact cats. In area 18, the similar difference was found in monocularly deprived cats only. It was shown that the differences in the mean sizes of cells are due to the increase of the number of large cells. In strabismic cats, the portion of large cells (soma > 200 mkm2) in area 17 was 58% and in area 18 was 8%. The relative share of large cells in areas 17 and 18 of monocularly deprived cats was similar (28 and 26 % correspondingly). These data show that early binocular vision impairments may lead to the changes in cytoarchitecture of cortical layers where the interhemispheric connections originate.