A wavelet based detection and analysis of gamma rhythms in EEG signals

Until recently, it was assumed that there was no valuable signal above BETA range (13-30 Hz) in EEG signals. But studies have confirmed that there exist some frequencies above 30 Hz termed as Gamma rhythms. In this paper, a new method has been proposed to detect Gamma rhythms in wavelet domain. Further, the detected Gamma rhythms have been analyzed in terms of their energy contents during different activities in different regions of brain. These results have been shown over brain topography plots. It is observed that Gamma rhythms are present in varying concentration over different regions of brain during different activity of brain. Next, a composite analysis has been done to study the intensity of alpha, beta and gamma waves during different activities of the brain. This information may be useful in identifying sub-normal brain activity in different region. Thus, it can help a lot in diagnosing neural disorders and thus can be of great help in the area of telemedicine.