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Половые и возрастные особенности функционирования мозга при выполнении задачи на произвольное переключение зрительного внимания (фМРТ-исследование)
The present study examined changes in brain functioning during voluntary visual task switching in healthy adult men and women. One hundred and forty subjects between 20 and 65 years old (69 men) participated in the study. In the fMRI task, the participants had to shift their attention between two objectives (classifying figures according to their form or number). Volumes of gray and white matter throughout the brain and in selected areas were calculated using VBM (voxel-based morphometry) analysis. The results of fMRI study revealed that in subjects of different age and sex task switching is carried out by bilateral dorsolateral prefrontal cortex, inferior parietal area and lateral occipital gyrus. It was also revealed that there is a transition from local to diffuse activation occurring with age. When comparing the two young groups (aged 20 to 30) we found that men had significantly higher activation in prefrontal cortex bilaterally, right parietal lobe and insula and moreover they had activations in supplementary motor area which were not observed in women. We did not found any significant differences between groups of elderly men and women (aged 51 to 65). The research found no significant correlations between BOLD-signal and age for the women between 20 to 40 years of age and for the men between 20 and 55 years of age. With further increase of age in both groups we found a consequent increase in the number of brain areas which are activated. VBM analysis revealed significant decrease in the volumes of gray, but not white, matter with age. However, no significant correlations with age and BOLD-signal were found between changes in the volumes of gray matter throughout the brain and in selected areas.