Numerical analysis of electroencephalographic data

Correlation of electroencepholographic data recorded simultaneously from several different regions, although promising important insights into the nature of the EEG generating process had been impeded by the prohibitive cost of special equipment or computer time until the introduction of the FFT. Now one is able to analyze the statistical structure of an EEG and explore the biological meaning of its parameters. Power spectra of EEGs in mono- and dizygotic-twins are shown to illustrate how modern techniques can be used to assess the individuality of the spontaneous working EEG. Other examples show the possibility of investigating the relations between simultaneous recordings from different parts of the brain while awake and asleep. EEG analysis is still at its beginning, subject to the data gap between the gross activity from macroelectrodes and the electrical activity from microelectrodes at individual neurons.