Under the term erection – Latin also ergio, which means as much as excitation or erection – the medical profession describes a stiffening of the male sexual part. The penis becomes stiff as a result of various mechanical or psychological stimuli. Primarily, the stiffening occurs due to sexual arousal. The blood inflow into the penis is increased and at the same time a blood outflow from the erectile tissue is throttled, so that the penis can become stiff or remain stiff. The stiff penis is a prerequisite for the consummation of penetrative sexual intercourse.
What is an erection?
Under the term erection, the medical profession describes a stiffening of the male genitalia. Illustration shows male genital area. Before an erection, arousal comes into effect. This arousal is a whole-body feeling of well-being. The man notices a muscle tension; subsequently, blood flows into the genitals. As a result, the penis becomes stiff, the scrotum begins to tighten, and the testicles are slightly pulled upward. In uncircumcised penises, the foreskin slides back, revealing the glans. In addition to blood pressure, the pulse also increases; blood is subsequently transported to the penis. As a result, the head of the penis turns dark red. In the further course, the vessels at the shaft of the penis become visible. The whole body is under tension; likewise, accelerated breathing can be perceived. This is followed by orgasm and ejaculation. After the man has experienced his orgasm, the so-called relaxation phase occurs. During this, a comfortable body sensation spreads; the erection decreases, the pulse becomes regular and the blood pressure normalizes.
Function and task
In order for an erection to take place, an extremely complex interaction of messenger substances, nerve stimuli and also blood circulation and muscles is responsible. All those factors – in perfect unison – make an erection possible. The penis is supplied – in the flaccid state – by three erectile bodies, which contain only an extremely small amount of blood. These are contracted smooth muscle strands, which are found in the arteries. Due to them, it is possible that in the erect state not too much blood is pumped into the corpus cavernosum. Erection is controlled by the sympathetic nervous system. The sympathetic nervous system is a so-called nerve plexus that radiates from the upper thoracic spine to the genital region. If the man is sexually aroused by words, images or even touch, the brain automatically sends messages. This is the “erotic stimulus”. After that, the parasympathetic nervous system – the “antagonist” of the so-called sympathetic nervous system – takes control. It sends the flow of information between the spinal cord and the genital area. Since the penis has very sensitive nerves, when touched directly the sexual stimulus can be processed and passed on immediately in the lumbar spine. In the process, the sensation is amplified and intensified. Subsequently, a chemical reaction chain is triggered by the nerve signals. Nitric oxide is released first, followed by cyclic guanine monophosphate. Those messenger substances activate protein kinase G. Then the process of erection begins: the veins start to dilate, the blood subsequently flows directly into the corpus cavernosum, causing the penis to swell. Due to the blood filling, the smaller veins located directly in the penis are squeezed. Thus, blood outflow is automatically prevented. The erectile tissue suddenly has 40 times more blood than in the non-erect state. The strength of the erection depends on the guanine monophosphate level. If more messenger substances are available, the erection becomes more intense. If there is only a low level, the erection is limited or non-existent, or the man cannot maintain the erection for long. Phosphodiesterase 5 – also known as PDE-5 – causes the erection to subside. This is an endogenous enzyme that reduces the blood supply so that the penis becomes flaccid again. That process does not always have to occur after an orgasm.
Diseases and ailments
It is possible that the man no longer achieves an erection. If erectile dysfunction is present, the medical profession calls it erectile dysfunction. The causes of erectile dysfunction are diverse; predominantly psychological, mental as well as organic reasons can be responsible.However, so-called PDE-5 inhibitors have been available for some time. These can be taken so that an erection can still be achieved. Phallography is used as part of the diagnosis. This allows the physician to detect the nocturnal erection and check its intensity. The physician attaches a strain gauge to the penis, which is then connected to a recording device. When the erectile tissue begins to fill, the doctor can then evaluate the measurement. With this method it is possible to find out physiological or psychogenic causes, which are responsible for the erection problems. Sometimes, however, priapism may also be present. This is a painful permanent erection that lasts for at least two hours. In this case, immediate medical treatment is necessary. If no urological treatment takes place, permanent damage to the corpus cavernosum may occur. Thus, the erectile function of the penis may be permanently disturbed or even lost.
