Nocturnal Erections and Other Responses

Sleeping spooned up with Ruf, I am often awoken by the fluttering of his penis as it hardens and then softens again. Sometimes these nocturnal erections are more insistent than others – depending upon how often he has had sex/masturbated recently or how exhausted he is physically – and are closely followed by the initiation of relations.

In days gone by, I can remember being upset by my ex’s ‘prodding broomstick’ treatment which tended to involve him rolling over and rubbing it against me in expectation of intercourse without any other form of prior intimacy and, often, after we had had a row in the hours before bedtime. Invariably he received short shrift in response.

I wanted to find out more about the involuntary stiffy and I was interested to learn recently that, in addition to the usual sexual response version, there are actually three other types of penile engorgement – reflex, psychogenic and nocturnal erections.

Nocturnal Erections

Nocturnal penile tumescence as it is medically known can occur up to four times during the night, with each response lasting up to 30 minutes. They are experienced by most healthy males of all ages but scientists have deemed them to be very different from sexually stimulated erections.

This is because all the body’s natural healing mechanisms come into play at night when there is less physical activity and this allows all the internal organs to receive increased blood flow. Whilst, during the day, most men can control the effects of this natural vascular circulation, at night, those controls are relaxed and so unsolicited erections result from the natural engorgement and oxygenation.

There are many theories as to the cause of night time erections and, by extension, the fabulous Morning Glory. One of the most believable is the build-up of nitrous oxide in the blood, released by the blood cells as a direct side effect of all that nocturnal vascular dilation. This could also explain why women experience similar horniness first thing in the morning, since their genitals also require oxygenation and so the vagina and clitoris will be similarly engorged at times during the night.

Reflex Erections

What parent has not noticed their infant son’s erection on having a nappy removed or being placed in a warm bath? These are obviously not the result of sexual stimulation but a reflex reaction to atmospheric stimuli.

Reflex erections occur when signals triggered by touching the penile shaft are carried through the pudendal nerve to the sacral nerves S4-5 in the lower spinal cord. Stimulation of S4-5 sends parasympathetic signals to the penis and leads to a reflex erection.

In adults, such signals tend to be caused by vibration or clothes rubbing against the penis and, because they are controlled by a bundle of nerves at the base of the spine, rather than the brain itself, can also be experienced by men with spinal injuries.

Psychogenic Erections

This third type of erection is arousal caused by erotic thoughts and can occur through stimulation of any of the five senses – sight, smell, hearing, taste or touch. Such stimulations cause neural signals originating in the limbic system of the brain to be transmitted through spinal cord to the erection centre at the base of the spine, resulting in increased blood flow to the penis.