<unk>  is a spontaneous erection of the penis during sleep or when waking up. Along with<unk>  clitoral<unk> , it is also known as sleep-related erection, morning glory or morning wood. Men without physiological erectile dysfunction or severe depression experience<unk> , usually three to five times during a period of sleep, typically during rapid eye movement sleep.<unk>  is believed to contribute to<unk>  health.
Nocturnal penile tumescence
Nocturnal clitoral tumescence
Premenstrual water retention
Nocturnal enuresis
Morning pseudoneutropenia
Task-invoked pupillary response
Clitoral erection
Post-void dribbling