Interhemisphere power ratios of cortical potentials in the 1-60 Hz band during the formation and testing of a cognitive set to a facial expression

摘要

Interhemisphere cortical potential power ratios were studied in the 1-60 Hz band during the prestimulus period at the stages of formation and testing of a cognitive set to a facial expression. Different topographies in the patterns of asymmetry in subjects with different levels of set expression were demonstrated. At the formation stage, the group of subjects without actualization of the set (n = 11) showed significantly higher power levels at gamma frequencies (21-40 and 41-60 Hz) in the frontal areas of the right hemisphere and at frequencies at 2-7 and 8-13 Hz, also in the frontal areas, but in the left hemisphere. At the set testing stage, the main topographic asymmetry pattern in these subjects persisted. In subjects with marked set actualization (n = 18), formation was characterized by a different topographical asymmetry pattern, with significantly higher power levels at gamma frequencies seen in the posterior temporal and occipital areas of the left hemisphere at frequencies of 2-7, 8-13, and 14-20 Hz, also in the posterior areas, but in the right hemisphere. At the set testing stage, the phenomenon of interhemisphere asymmetry in the power of cortical potentials was not seen.