RELATIONSHIPS BETWEEN THE ATTENTION NETWORK FUNCTIONING AND SPONTANEOUS EEG ACTIVITY IN PATIENTS WITH CORONARY ARTERY DISEASE

The cognitive decline in cardiac patients may be associated with insufficiency of the cerebral blood supply and inhibition of the brain functional state that manifested as a slowing of spontaneous EEG activity. On the other hand, the attention networks functioning is closely related to the theta oscillatory activity. We have studied the relationship between background theta activity (4-6 Hz) and attentiveness networks functioning in patients with severe coronary artery disease (CAD). Material and methods. We evaluated the parameters of alerting, orienting and executive control using the attention network test (ANT) in 41 CAD patients. Resting-state EEG with closed and open eyes also was recorded from 62 channels positioned according to the International 10–20 system. Spectral EEG power was calculated for frequencies from 0.1 to 50 Hz. Statistical analysis was done using Statistica 10 software package. Results and discussion. The regression analysis revealed positive associations of alerting and the theta rhythm (4-6 Hz) power with eyes closed in the right central and temporal brain regions. Negative relationships between the alerting system and the theta rhythm power in the right frontal and left occipital sites were obtained. Orienting system was positively related to the theta reactivity in the left temporo-parietal and right central brain areas; a negative relationship was established for the right occipital site. The executive control correlated negatively with the reactivity of the theta power in the right frontal and left parietal areas of the cortex, positively – right central region. It was demonstrated that attention disorders in CAD patients are associated with theta activity changes, predominantly in the right hemisphere. The study of EEG resting-state parameters can be useful for predicting impaired attention in patients with cardiovascular diseases.