Related Experiment Video
Updated: Apr 16, 2026
08:45
Polygraphic Recording Procedure for Measuring Sleep in Mice
Published on: January 25, 2016
25.8K
Comparison between human awake, meditation and drowsiness EEG activities based on directed transfer function and MVDR
Chamila Dissanayaka1, Eti Ben-Simon, Michal Gruberger
1School of Electrical and Computer Engineering, RMIT University, GPO Box 2476V, Melbourne, VIC, 3001, Australia, s3315014@student.rmit.edu.au.
Medical & Biological Engineering & Computing
|March 17, 2015
Summary
This study reveals that meditation and drowsiness significantly alter brain information flow (effective connectivity). Meditation uniquely increases delta band activity originating from frontal, parietal, and occipital regions, highlighting changes in brain connectivity with attentiveness.
Area of Science:
- Neuroscience
- Cognitive Science
- Signal Processing
Background:
- Attentive states like meditation and drowsiness are associated with altered brain activity.
- Understanding changes in brain connectivity during these states is crucial for cognitive neuroscience.
- Electroencephalogram (EEG) analysis offers a non-invasive method to study brain functional and effective connectivity.
Purpose of the Study:
- To compare functional connectivity (coherence) and effective connectivity (information flow) during awake, meditation, and drowsiness states.
- To evaluate the suitability of Welch and Minimum Variance Distortionless Response (MVDR) methods for coherence estimation.
- To investigate changes in the brain's information flow using the Directed Transfer Function (DTF) method across different attentional states.
Main Methods:
- EEG data from 30 subjects (10 awake, 10 drowsy, 10 meditating) were analyzed.
- Functional connectivity was assessed using MVDR and Welch coherence methods.
- Effective connectivity was estimated using the DTF method on data from electrodes F3, F4, C3, C4, P3, P4, O1, and O2.
- Statistical analysis involved Kruskal-Wallis tests with Bonferroni correction.
Main Results:
- MVDR coherence demonstrated higher spectral resolution and suitability compared to Welch's method.
- Both drowsiness and meditation states significantly altered effective connectivity as measured by DTF.
- A significant increase in delta frequency band information flow was observed exclusively during meditation, originating from frontal, parietal, and occipital regions.
Conclusions:
- Changes in attentiveness significantly alter the spectral profile of brain information flow and functional connectivity.
- Coherence and DTF analyses are effective in capturing these changes in brain connectivity.
- Meditation is associated with distinct patterns of increased information flow in specific frequency bands and brain regions.
