[Age-related features of the microstructure of layer V of human frontal lobe cerebral cortex].

Age related peculiarities of the microstructure of areas 8, 10 and subarea 32/10 in layer V of human frontal cerebral cortex were studied in left hemispheres of 103 individuals from birth to 20 years of age using histological methods and computer morphometry. Profile area of pyramidal neurons, radial fiber and fiber bundle thickness, and the distance between bundles were measured. During postnatal development of layer V in frontal cerebral cortex the following stages were distinguished: from a birth till 1 year, from 1-2 years till 5-6 years, from 6-7 till 9 years, from 9-10 years till 16-18 years. In each stage, the complex of microstructural changes was detected that was caused by increasing complexity of a system of transthalamic and other frontal cortex connections with other cortical and subcortical formations.