Nasal and sleep cycle--possible synchronization during night sleep.

Regular cyclic changes in nostril airflow due to a nasal congestion and decongestion are known in literature as nasal cycle. Registration of breathing from each nostril separately gives possibility to registrate moments of alternative change of airflow of nostrils and periods of nasal cycle. This registration during night sleep shows that the length of these periods are about 1.5h, 3.0 h and 4.5h. The length of these periods are multiple of mean length of sleep cycle--about 1.5h. The alternative change of airflow through nostrils occurs through some of REM stages of the sleep. This shows, that during the night sleep becomes synchronization of nasal and sleep cycles in some of the REM phases of sleep. As a result--length of periods of the nasal cycle are one or more length of sleep cycle.