Non-rapid eye movement sleep activation occurs during NREM that is comparable to the type that occurs during REM. It is this sub-cortical activation that results in dreaming during the NREM stage during the morning hours. During non-REM sleep, the tonic drive to most respiratory muscles of the upper airway is inhibited. This has two consequences: However, because the diaphragm is largely driven by the autonomous system, it is relatively spared of non-REM inhibition. As such, the suction pressures it generates stay the same. This narrows the upper airway during sleep, increasing resistance and making airflow through the upper airway turbulent and noisy. For example,
Rapid eye movement sleep behavior disorder The actions in an episode can result in injuries to oneself or one's bed partner. The sleeping person may be unaware of these movements. Dreams often involve violent or aggressive actions, and an attack theme like being chased by people or animals. Because violence in dreams is more likely to be recalled, this could be an artifact of recall bias or selection bias. The individual with RBD may not be aware of having it. In a normal sleep cycle, REM sleep may be experienced at intervals of between 90 minutes and two hours every night, which means RBD episodes may