Measuring the Coupling Direction between Neural Oscillations with Weighted Symbolic Transfer Entropy

Area of Science:

• Neuroscience
• Computational Neuroscience
• Signal Processing

Background:

• Neural oscillations are crucial for brain processing and communication.
• Understanding directional interactions between brain regions requires accurate estimation of neural coupling direction.

Purpose of the Study:

• To develop a novel method, weighted symbolic transfer entropy (WSTE), for measuring directionality between neuronal populations.
• To improve upon traditional symbolic transfer entropy (STE) by incorporating amplitude information.

Main Methods:

• Developed WSTE by combining symbolic transfer entropy (STE) with a weighted probability distribution.
• Validated WSTE using simulation analysis to assess its ability to estimate coupling direction.
• Applied WSTE to epileptic electrocorticography (ECoG) data.

Main Results:

• WSTE effectively estimates coupling direction between neural oscillations in simulations.
• WSTE demonstrates higher sensitivity to coupling strength and improved robustness against noise compared to STE.
• A significant coupling direction from the anterior nucleus of thalamus (ANT) to the seizure onset zone (SOZ) was identified in epileptic ECoG data.

Conclusions:

• WSTE is a superior method for measuring directional coupling between neural oscillations.
• The WSTE method offers advantages for characterizing information flow between brain regions.
• This technique has potential applications in understanding neurological disorders like epilepsy.