Dynamics of EEG Spectral Characteristics in Subjects with Various Trait Anxiety Levels Performing Cognitive Tests

Abstract

EEG spectral power (θ1-, θ2-, α-, β1- and β2-ranges) was studied in subjects (n = 43, men, aged 18–21 years) with various trait anxiety levels during attention testing. Trait and state anxiety levels were assessed according to Spielberger prior to testing. In the initial state with the eyes open, subjects with low trait anxiety demonstrated significantly higher power of the EEG θ1- (in the occipital and left parietal cortical regions) and θ2- (in the left frontal and right temporal regions) bands than those with high anxiety level. At the same time, lower power of the EEG α-band (in the left central and frontal regions) was observed in subjects with high trait anxiety level, comparing to those with low anxiety levels. During the test, subjects with low anxiety demonstrated significant increase of spectral power in θ1- and β2-EEG frequency ranges in all areas of the cortex (except for the temporal region) compared with the preceding periods (with the eyes open). The increase of spectral power in the EEG θ1-band was also found in subjects with high trait anxiety level during the test. However, there was no intensification of β2-rhythm of the EEG. One can assume that the revealed patterns of EEG index dynamics reflect the domination of either orienting or defensive component in the motivational structure of subjects with different trait anxiety levels.