Patient's question:
What is the reason for abnormal nocturnal penile erection?Doctor's answer:
Some men feel uneasy about frequent nocturnal erections during sleep, worrying whether there is something wrong with their penis. In reality, this concern is unnecessary.Erection is a natural instinct for men. Starting from adolescence, if exposed to certain sexual stimuli in daily life, it can trigger erections, which is a normal physiological response. It is also normal to occur during sleep and is not a pathological condition. According to data, teenage boys may experience about six erections per night, each lasting 20–30 minutes. Young adults average 60–90 minutes of erection per night, while the frequency decreases in middle age. However, healthy elderly men over 65 still experience several erections each night. Urologists use nighttime erections as one criterion for assessing sexual function.
Erections are controlled by the body's autonomic nervous system and have a unique physiological structure. The penis consists of three long cylindrical corpora cavernosa. These corpora cavernosa are rich in vascular plexuses. When sexual arousal occurs, the valve-like sphincter closes, allowing a large amount of blood to flow in, causing the corpora cavernosa to gradually expand and the penis to become erect and hard. When arousal decreases or after ejaculation, the arteries in the penis contract, reducing blood flow while increasing venous, causing the corpora cavernosa to shrink, and the penis returns to its resting state. This is why the penis can be both elongated and retracted.
Some people believe that erections are often related to sexual dreams. In fact, most nighttime erections are not caused by sexual impulses, as only a small number of people experience sexual dreams. Even if a man has recently had sexual satisfaction, the frequency and intensity of erections remain unchanged. From a physiological perspective, human sleep can be divided into two phases: non-REM (NREM) sleep and REM (Rapid Eye Movement) sleep. These two phases alternate 4–5 times per night. An experiment was conducted where people were awakened from either NREM or REM sleep and asked to recall their state before waking. The results showed that 85% of those awakened from REM sleep reported dreaming, while those in NREM sleep reported being in a deep sleep without dreams. Most nighttime erections occur during REM sleep, leading some to believe they are related to sexual dreams. However, erections can also occur during NREM sleep without dreams, and since normal people do not have sexual dreams every night but experience several erections, it is clear that nighttime erections are mostly unrelated to sexual impulses.
Whether the penis is erect during nighttime sleep is also a reliable indicator of its ability to become erect while awake. If the penis is erect during sleep, it indicates normal sexual function. Conversely, if there is no erection, it may suggest an organic disorder. Doctors often use this as a basis to differentiate between psychological impotence and organic impotence. Erections during sleep are associated with psychological impotence, while the lack of erections is linked to organic impotence. However, if an erection persists day and night accompanied by pain, it is considered a prolonged abnormal erection and should be treated by a doctor.