Coherence Analysis of EEG Signal Using Power Spectral Density

Coherence analysis can be detect for coordination of EEG rhythms between brain areas. It could not reflect the dynamic properties changing with time. Coherence analysis is a method developed on base of classic coherence analysis and signal´s joint time-frequency representations in recent years. It was used to extract transient characteristics of interactions among brain areas. It describes the temporal, spatial and frequency relationships of brain activities. This paper discuss the frequency-varying coherence of EEG (Electroencephalogram) to study the coordination mechanism of brain. The power spectral density is the frequency-varying method to study the coordination mechanism of brain areas. The Welch method and the periodogram method are the two methods to study the power spectral density. The results showed that appropriate methods were effective tools for EEG to study the coordination between brain areas.