System for studying the topography of delta rhythm during sleep: further development.

A hybrid system for treatment of all-night sleep EEG records is described, which leads to the representation of sleep cycles by the continuous variation of the amplitude in a given frequency band. This system constitutes the development of a previous purely analogic one. The addition of a micro-processor and of a small computer renders the system far more flexible and easier to use. The results stored on tape are available for further treatments.