The effects of multitask cognitive training on EEG changes and neurovascular unit markers in cardiac surgery patients

Background: Understanding the neurophysiological mechanisms that contribute to better cognitive functioning is a research area that has been subject to growing interest. It is assumed that multitask interventions have better results in cognitive recovery. This study aimed to evaluate the effects of multitask cognitive training (MСT) on electroencephalographic (EEG) changes and markers of the neurovascular unit (NVU) in cardiac surgery patients.
Methods: A prospective cohort study was conducted on 62 cardiac surgery patients between 45 and 75 years old, with 30 of them going through a 5-7-day MCT course. The groups had similar clinical indicators at baseline. Before and after cardiac surgery, EEG studies were carried out. The NVU indicators (S100, NSE, and BDNF) were analyzed in three stages: before surgery, during the first 24 hours after surgery, and 11-12 days after CABG.
Results: After CABG, patients with MCT course and controls had higher theta1 power values as compared to preoperative data. The indicator of relative changes confirmed that the control group had more significant changes (p = 0.001). The increase in S100 concentrations was only observed in the control patients during the first 24 hours after CABG. At the end of the training course, the MCT group had an increase in BDNF levels compared to their preoperative values. The control group had a low serum BDNF concentration.
Conclusions: Theta activity changes and S100 and BDNF markers showed a slight decrease in the severity of brain damage in cardiac surgery patients after a short MCT course. Monitoring the process of cognitive rehabilitation in cardiac surgery patients can be made more informative using EEG and NVU markers.