High-Frequency Resolution EEG: Results and Opportunities

.Spectral EEG characteristics are usually reduced after fast Fourier transform (FFT) to the absolute or relative power values for several conventional frequency bands such as alpha, beta, theta, etc. In many cases such analysis is sufficient, but in most cases it does not distinguish between dynamically changing brain states, probably because the concept of an EEG rhythm is too general. Recent data indicate some inconsistencies in traditional frequency bands and a heterogeneity of conventional EEG rhythms. This paper reviews the present state of the art in the field of FFT-based spectral EEG analysis and describes the results and opportunities of higher frequency resolution EEG approach to the understanding of dynamic brain processes.