[A quantitative analysis of the architectonics of the brain cortical fields during aging].

Under study was the cytoarchitectonics of motor cortical fields 4 and 6 and speech cortical fields 44 and 45 in man. Special attention was given to changes of neuron density in layers III and IV, change of the square area of the profile field of neurons and their nuclei, variability of the cellular composition. The investigation has revealed the decreased neuron density, less square area of the profile neuron field and their layers and rearrangement of the neuronal composition of cytoarchitectonic layers. Individual specific features of the process of aging of the brain in different individuals are noted.