Erection (from latin ‘erigo’, ‘erectum’ – to lift, erect, build) is a phenomenon when penis increases in size, becomes firm and enlarged. Erection makes it possible for penis to enter the vagina and make a sexual contact. Penile erection is a process when penis or clitoris are reflexively filled with blood that gives these organs needed firmness. Erection (from latin ‘erectio’) is an enlargement and firmness of penis as a result of venous blood filling the corpora cavernosa; it occurs when impulses are transferred from nerves to corpus spongiosum during the sexual stimulation. Erection is a sexual activity of penis that becomes larger and harder (as a result of blood filling the corpora cavernosa) and can enter a vagina. This term is also related to a clitoris being in the phrase of sexual stimulation. Erection is the most elementary, long staying and vulnerable phenomenon of men’s sexuality.
Erection mechanism seems to be an elementary process. It is determined by the smallest amounts of integrated anatomy-physiological structures and the predominance of peripheral locations that preserve a considerable part of autonomy (spinal, para spinal and vegetative knots and interlacements). The considerable stability of erections is conditioned by their protection from damaging factors of organic nature. This process is determined by the most ancient phylogenies structures. This is the reason why from all displays of men’s sexuality erections are formed and revealed the first – long time before a libido, ejaculations and orgasms. Erections are already observed in boys in pectoral age. At the same time erections are rather sensitive to all kinds of mental damaging processes. Erections are under the control of highest cerebral mechanisms, for example, they are controlled by negative emotions.
Often erections are shown like a phallic cult in myths and fetishism of many peoples. It’s like a symbol of men’s courage and dignity. Erection is a reflex vascular act. The main mechanism of erection is explained by arterial blood influx strengthening. The deceleration of blood outflow in veins plays an auxiliary role in erection process. The vein affect becomes stronger with mechanical rise of the penis. In most cases penis firm is influenced by physical irritants (visible, acoustic, sensual and touchable) that enter the cortex and stimulate the sexual centers of brains, exciting the erection center in the spinal cord. Erection can appear when the head of penis is irritated in a mechanical way, under the influence of sexual fantasies that cause sexual stimulation in men.
From the physiology point of view, the mechanism of penis erection is studied well. It is presented as a complicated chain of neuro-humoral processes that can be divided into three parts: 1) expansion of arterial channel; 2) relaxation of involuntary muscles in the corpora cavernosa; 3) block of venous blood outflow. These all results in blood filling the corpora cavernosa. The outflow process ‘freezes’ and penis enlarges and becomes hard.
Penile erection plays an important role in sexual activity. When penis is in its common condition it cannot enter the vagina. Only in resilient and hard form it enters a woman’s vagina. Erection is a conditioned reflex in the beginning of sexual life. With time its instinctive character is developed by a wide range of possibilities according to self-reflex mechanism. Various pictures of women, memories, visible, acoustic and emotional impressions influence men’s mental sexual center and are followed by a penile erection. Sexual life assists sexual stimulation and men’s eagerness to have sex. In the future penis tension is supported by mechanical exciters. A head and skin of penis receive these exciters during the sexual activity.