A software package for the study of REM-sleep microstructure

This package, written in the Matlab/Octave language, have been used in our laboratory to quantitatively determine the REM-sleep microstructure by analyzing the ElectroOculoGraphic (EOG) signal recorded during sleep. The REM-sleep microstructure consists in the alternation of four sub-stages inside a REM-sleep period. This alternation is due to two important phenomena reported in the literature: 1) Rapid Eye Movements (REMs) are significantly present only in "phasic" sub-periods of REM-sleep periods, and are absent or poorly present during "tonic" sub-periods. 2) In addition to REMs, also Slow Eye Movements (SEMs) occur during REM-sleep periods. The sub-stages are respectively characterized by: No enhancement either of SEMs or REMs (sub-stage 1); Selective enhancement of SEMs ( sub-stage 2); Selective enhancement of REMs (sub-stage 3); Enhancement of both SEMs and REMs (sub-stage 4).