Male erection includes reflex erection, nocturnal sleep erection and psychological erection, etc. 1. Reflex erection: refers to the erection caused by stimulation of the penis or the tissues around the penis, which is accomplished by nerve reflexes. 2. Nocturnal sleep erection: During the night sleep, the nerves that inhibit erection are inhibited, and the penis is not under the control of autonomous consciousness and produces erection, which usually lasts for about half an hour and will subside by itself, which is a normal physiological phenomenon. 3. Psychological erection: refers to the visual, auditory or hallucination stimulation of the brain, this stimulation signal is transmitted to the penile nerve, thus causing penile erection. If patients find erection abnormalities, please seek medical treatment in time and treat them actively so as not to delay the condition.