Erectionmeaning penile erection, refers to hardening of the penis, the male sex organ. Penis becomes hard because of filling of blood in the spongy tissues of the organ. This is an active neuro- haemodynamic process that is influenced by hormones and environmental factors.
To understand about erection in a simple way let us understand the Anatomy and Physiology of Erection.
How Erection Occurs?
Erection occurs when a man is excited due to sexual arousal or due to certain stimuli like watching a porn, sexual thoughts, reading a book with sexual theme, listening to exciting music etc. In such situations, hormones are released in the body which activate a combination of several factors leading to erection.
What Is Anatomy?
Penis is a male organ which is partly inside the body and partly outside the body which can be seen and felt. The inner part is attached to the pelvis and is known as the root of the penis. The outer portion, which is cylindrical in shape, free and pendulous, covered by skin is known as body of penis.
Penis contains 3 spongy structures called the right corpus cavernosa the left corpus cavernosa and the middle one, the corpus spongiosum which have the erectile tissues. In the middle of corpus spongiosum is a tube-like structure called urethra which acts as passage for urine and semen.
The corpus spongiosum ends to form a soft, cervical and sensitive structure called the glans penis. The skin over the penis is thin and loosely attached which extends beyond the glans penis forming the prepuce or the foreskin.
Penis is richly supplied by blood supply from the internal pudendal artery. The arteries run inside the corpus cavernosa tissues which are erectile and get hardened when the blood flows into them during erection.
Veins of the penis are complex and are well intricated which get compressed during an erection and prevent the blood from draining away from the penile tissues during erection. The autonomic nervous system within the penis is responsible for the erections.
Physiology of Erections
Erection is a process that is under nervous control that promotes a vascular response in the tissues of the penis. The central nervous system plays an important role as there are special areas in the brain associated with sexual responses and by production of neurotransmitters that take part in the process of erection.
Sensory signals from the genitals are potent activators of pro-erectile system which elicits erection. During arousal as sexual stimulation occurs, excitatory signals originate in the brain and the neurotransmitters produced by excitatory nerves such as nitric oxide and prostaglandins cause relaxation of the smooth muscles of the penile arteries present in the corpus cavernosa.
As the smooth muscles of the blood vessels of the arteries relax, blood flows into and fills up causing hardening of penile tissues. The filling of blood in the arteries due to relaxation of the muscles in the blood vessels combined with a decrease in the blood draining away from the penile tissues, due to compression of the veins, causes engorgement of penis which becomes hard resulting in erection.
Types of Erections:
There are three types of erections:
- Nocturnal Type – Erection which occurs during sleep and follows the REM (rapid eye movements) sleep.
- Reflexogenic Type – Erection which occurs from genital stimulation.
- Central or Psychogenic Type – Erections which occur due to factors like smell, visual stimuli, and other external stimuli.
Erections slowly reduce after ejaculation or sometimes on their own. So, dear men, sound knowledge is very important. Do not get carried away or confused by the extensive information, out there on the internet. Trust qualified doctors only, as regards your health.