THE TOPOLOGICAL FEATURES OF THE BRAIN ACTIVITY DURING MULTITASK COGNITIVE TRAINING IN THE POSTOPERATIVE PERIOD CORONARY ARTERY BYPASS GRAFTING

Highlights

It has been demonstrated for the first time that multitasking cognitive training reduced the density of low-frequency current sources in the frontal and temporal regions of the brain involved in encoding memories and regulating general brain activity in patients after coronary artery bypass surgery.

Aim. To study the topological features of brain activity assessed using the standardized low-resolution brain electromagnetic tomography (sLORETA) method in patients with multitasking cognitive training after coronary artery bypass grafting (CABG).

Methods. A prospective study enrolled 100 patients admitted to the hospital for CABG, aged 45 to 75 years. All the patients were randomly assigned to a group with multitask cognitive training (MCT) or a comparison group without training (n = 50). The MCT protocol included a postural task performed simultaneously with cognitive tasks involving mental arithmetic, verbal fluency, and the unusual use of a common object. The MCT course was conducted daily, starting 3–4 days after CABG, and lasted 5–7 days. Standardized low-resolution brain electromagnetic tomography (sLORETA) was used to localize current density sources to assess the topography of changes in brain electrical activity.

Results. It was found that there was a decrease in the frontotemporal density of current sources at frequencies of 3–5 and 5–7 Hz after MCT during the early postoperative period CABG, compared to preoperative values (t > 3.43; p < 0.003 and t > 3.53; p < 0.007). Between-group differences were observed in the mediobasal regions of the brain; patients after MCT had a lower density of activity sources in the 3–5 Hz range compared to the group without training (t > -3.48; p < 0.04).

Conclusion. The MCT helped to reduce low-frequency activity in patients after coronary artery bypass grafting (CABG). Topographic features were associated with the frontotemporal and medial basal regions of the brain, which are involved in memory encoding and regulating general brain activity. These findings emphasize the significance of investigating neural mechanisms underlying the effectiveness of multitasking interventions in cognitive rehabilitation. The data obtained can be utilized to develop and conduct future research aimed at enhancing cognitive rehabilitation programs.

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