ABSTRACT
This chapter presents electroencephalogram (EEG) alterations to determine whether meditative states can be distinguished from other states of consciousness. Methods of classical electroencephalography were combined with computerized spectral analysis and correlated with subjective data. A push-button with a code of 5 signals permitted the subjects to indicate the psychological events occurring during meditation or relaxation: body sensation, involuntary movement, visual imagery, deep meditation and transcendence. A program used the Fourier Transform to produce a succession of EEG spectra in time. Meditation brought about particular responses to flash and click stimuli administered to seven subjects during different stages of the practice. Involuntary movements similar to those of early sleep could occur at the beginning of meditation, but disappeared in the deep phase. The main EEG alterations must be compared with those of other states of consciousness in an attempt to individualize the meditative state.
