Increased neurocardiological interplay after mindfulness meditation: a brain oscillation-based approach

After 8 weeks of Mindfulness Based Stress Reduction (MBSR) training, the correlation between alpha brain wave frequency and heart coherence increased significantly in the middle frontal and bilateral temporal regions. Alpha coherence and heart coherence showed similar changes, but alpha peak power did not. Standard spectrum analysis alone showed no difference before and after training. Individual alpha peak frequency is relatively stable, and its interplay with cardiac activity may be a more sensitive measure of brain-heart connection than power spectrum. This preliminary study involved eleven participants aged 28–52 years.

Study at a glance

Abstract

Background Brain oscillations facilitate interaction within the brain network and between the brain and heart activities, and the alpha wave, as a prominent brain oscillation, plays a major role in these coherent activities. We hypothesize that mindfully breathing can make the brain and heart activities more coherent in terms of increased connectivity between the electroencephalogram (EEG) and electrocardiogram (ECG) signals. Methods Eleven participants (28–52 years) attended 8 weeks of Mindfulness Based Stress Reduction (MBSR) training. EEG and ECG data of two states of mindful breathing and rest, both eye-closed, were recorded before and after the training. EEGLAB was used to analyze the alpha band (8–12 Hz) power, alpha peak frequency (APF), peak power and coherence. FMRIB toolbox was used to extract the ECG data. Heart coherence (HC) and heartbeat evoked potential (HEP) were calculated for further correlation analysis. Results After 8 weeks of MBSR training, the correlation between APF and HC increased significantly in the middle frontal region and bilateral temporal regions. The correlation between alpha coherence and heart coherence had similar changes, while alpha peak power did not reflect such changes. In contrast, spectrum analysis alone did not show difference before and after MBSR training. Conclusion The brain works in rhythmic oscillation, and this rhythmic connection becomes more coherent with cardiac activity after 8 weeks of MBSR training. Individual APF is relatively stable and its interplay with cardiac activity may be a more sensitive index than power spectrum by monitoring the brain-heart connection. This preliminary study has important implications for the neuroscientific measurement of meditative practice.