Lag Synchronisation in the Human Brain: Evidence from 17,722 Healthy Subjects’ EEG Analyses

摘要

Lag synchronisation of two different chaotic oscillators is phenomenon when the signal from the system with a lower frequency has some delay with respect to the system which has the higher frequency. The interaction among the multiple brain oscillators may produce such a phenomena. The purpose of this study was to determine if direction of phase difference between two channels in EEG does depend on the source characteristic frequency. Independence of phase shift on mean frequency between two channels was tested on group of 30112 healthy truck drivers. Mean phase difference between two EEG channels was estimated by Hilbert transform and compared to the difference of characteristic frequency. Number of EEG segments with the phase delay from the electrode with a lower frequency to the electrode with a higher frequency was significantly higher then to the electrode with lower frequency. The most significant direction of phase delay was fronto-occipital. The results support hypothesis about presence of lag synchronization in the brain. This work provides alternative explanation of the phase shift between oscillations in different part of the brain.