[Change in the human electroencephalogram during brief mental loads]

Frequency-amplitude characteristics of EEG beta-, alpha-, theta- and delta-rhythms were studied in 33 male subjects with different maximal velocity of effective processing of visual information. Dosed mental load enhanced the total activity of EEG frequency components of parieto-occipital parts of the brain. The most substantial changes were revealed in the delta-rhythm range. A statistically significant correlative connection was found between integrative amplitude values of EEG slow rhythms and success in performing mental tasks. The higher the maximal velocity of effective processing of visual information, the greater the magnitudes of theta- and beta-activity. No statistically significant connection has been revealed between the maximal velocity of effective processing of visual information and the frequency-amplitude EEG characteristics before and after mental loads.