EEG ALPHA-RHYTHM FREQUENCY AND INTELLIGENCE IN NORMAL ADULTS

The electroencephalogram (EEG) reflects stable individual differences in brain function and therefore can be a powerful instrument for explo ring the biological basis of intelligence. However, the question of wh ether the EEG, and, in particular, the alpha rhythm frequency (AF) is related to intelligence in normal adults remained unclear. We analyzed EEG spectra and performance on different intelligence rests in 101 he althy males aged 20 to 45 (M IQ = 119.2; SD = 9.4) with a special rega rd to brain region and specific mental abilities. Scores on Raven's St andard Progressive Matrices (SPM) correlated positively with AF in pre frontal and frontal regions. Verbal abilities factors derived from the verbal subtests of Amthauer's Intelligence Structure Test (IST) and H orn's LPS test of mental performance correlated positively with both m ean and peak AF factors (r = .34 and .35, correspondingly; p < .001). However, AF did not show any significant relationship with the factors of general (g factor), spatial, and arithmetic abilities.