Spectral EEG indicators of theta-rythm and efficiency of intellectual activity

The modified test known as „Regularity recognition“ was offered to 31 men (18-21 years old, right-handers). Test results allows to to determine the abilities for analysis and synthesis of visual information. The EEG was recorded at the beginning, during the experiment and after the test was completed. Two groups of testees were selected according the different success level. Main differences between selected groups were registered in Theta-1 range of several areas of the left hemisphere of the brain. The testees with better success level have had higher spectral power of Theta-1 range at the beginning of the experiment (О1 - 5,81+0,49 and 3,56+0,28, р=0,001; Р3 - 5,72+0,43 and 4,16+0,47, р=0,025; F3 - 10,44+1,25 and 6,44+0,68, р=0,008; Т3 - 2,45+0,25 and 1,80+0,14, р=0,032, in first and second group accordingly). Differences have been seen during the first and the third minute of test. According the experiment results we can suspect that low and high Theta-1 ranges may have different functional value and may be associated with different effectiveness of certain kinds of intellectual activities.