[Eye movements in sleep: towards a model]

The study of the REM-process by means of the oculomotor frequencies has shown that it is a stochastic point process. Therefore, the techniques utilized to quantify the time-dependency of this process were used. The structure of occurrence of REM's quantified by transition probability matrixes evidenced a two-state first order semi-Markov process. The oculo-motor configurations of REM-sleep revealed two independent entities, their number and their relative frequencies. This conclusion was used as a working hypothesis for the Spacelab 1 sleep-recording experiment in zero-gravity. The results confirmed the underlying hypothesis.