This is a personal theory based only on my own experiences. I hope it helps to clear up all the confusion we restorers are having concerning our newly found sexual responses.
It appears that two kinds of nerves participate in the male sexual response. These nerves respond to different stimuli and produce different responses. The two types seem to be:
These seem to be mutually inhibitory (each response suppresses the other). The glans response suppresses the foreskin response more than the foreskin suppresses the glans response.
These two responses seem to be mediated (that is, they converge and interact) in the frenulum where it is attached to the penile shaft.
The nerves in the foreskin (F nerves) are complete responses, meaning that any response is independent of the preceding response. They react to the rolling and stretching action of the foreskin. The nerves seem to produce an intensely strong, modified-tickle response that causes the internal body muscles to tense. These responses inhibit the response of the glans nerves.
The foreskin is also densely populated with specialized stretch receptors, which respond to being stretched during intercourse.
The nerves in the glans (G nerves) have a step function response, meaning that the intensity of each successive response increases, building upon the previous responses. The increased response only occurs when the second response occurs within a definite time frame. These nerves are triggered by pressure and friction, and give greater feedback as pressure and friction increase. These responses inhibit the response of the foreskin nerves.
These feelings are less pleasurable than the F sensations but more of a drive to reach climax. They impel the male to increase the action until the internal muscles of the groin area contract, forcing maximum penetration and prostate spasms associated with ejaculation.
The glans is sparsely populated with fine touch receptors. In fact, the glans is only slightly more sensitive than the heel of the foot. Its response is primarily to pressure and friction. Circumcision destroys many of the fine touch receptors that were present in the glans by tearing the foreskin away from the glans.
For intact or restored men who have sufficient foreskin, foreplay is often as pleasurable as intercourse because the F nerve response is so intense. The man is capable of enjoying a long period of slow stimulation, as opposed to the much faster, increasing stimulation that steps up the G nerve sensations. This prolonged period of slow stimulation partially inhibits the G nerve function.
Intact men experience a greater variety of sensations during sexual stimulation than circumcised men do. The action of the foreskin alternately covering and uncovering the glans stimulates both the F nerves from texture changes, and the G nerves from the pressure alternating on the corona of the glans. The foreskin also aids in keeping the penis moist and therefore more sensitive.
Intact men also have greater control over their level of sexual excitement than circumcised men do. All of the sensory input lets a man know how excited he is becoming and where in the process he is, so if he starts to get too stimulated by the G response, he merely draws the penis back into his sheath. The sheath dulls the friction part of the response (G) and satisfies him by substituting more stretch response and fine touch responses (F). This ability to retreat back into the foreskin while still feeling pleasure is why many intact men can enjoy the sex act for long periods without getting abraded. I personally find that even though I now have a lot more sensitivity and varied sensations, I also have greater control over when I reach orgasm than before I restored.
At early stages of intercourse, the strokes are long and slow. Each stroke pulls the glans back into the sheath, which slows down the G response while still giving the male pleasure. However, as the act continues, the G response slowly builds because the glans protrudes out of the skin sheath and is exposed to friction. The G response eventually takes precedence, suppressing the F response, and the male experiences the pressure and friction-induced climax.
During sex, various muscles of the body experience a level of contraction that corresponds to the pleasure of the act. This building up of tension and its sudden release at ejaculation constitutes a climax or orgasm. Intact men experience more stimulation than those who have been circumcised, which causes more muscles to contract and to contract more tightly. Therefore, during orgasm they experience a greater release, and generally have more intense orgasms, than circumcised men.
In circumcised men, except for possibly some frenulum remnant, the F nerves have been completely destroyed. The stretch receptors that are located entirely within the ridged band at the tip of the foreskin are also completely removed by circumcision. The only sensation left is the G response, and even this is minimized due to keratinization of the glans (the build-up of layers of dead skin as a protective response against the daily chafing of the exposed glans). As each stroke is a step response, a circumcised man is forced to increase the speed and force of the action to sustain pleasurable feelings. This, I believe, is why circumcised men rush through sex to the climax...they get little pleasure out of prolonging the act because there is little or no pleasure from the F response.
Because there is so little F response left, the remaining G response is very effective at inhibiting it. A circumcised man cannot draw his penis back into a sheath and substitute the stretch and fine touch responses for the pressure and friction responses, so he has very little control over his climax. Furthermore, if he stops moving to prolong the sex act, he will lose all pleasurable sensations. The step response of the G nerves declines slowly, so unless the man stops movement for a long time, he will find that the point of climax happens at the same time upon resumption of movement as it would have occurred had he not stopped.
An additional phenomenon that is a problem for some circumcised men is inability to reach climax or difficulty doing so. It is possible that the glans response alone cannot produce a climax, at least not without extreme levels of stimulation; some F nerve response is also required. This would explain why men who have lost too much of their F nerve response, or who are too heavily keratinized, may be unable to achieve a climax.
Ironically, circumcisionwhich is presented as a cosmetic procedure that does no harm to a mans sex lifemay be held responsible for many of the issues that appear in sexually unsatisfying relationships, such as premature ejaculation*, intercourse that doesnt last long enough for both partners to feel satisfied, and lack of interest in foreplay. Men who are circumcised have their glans under constant pressure and the G response builds very quickly to a climax, often without the necessary feedback for them to know how soon they are going to climax. Foreplay does little for them. The only way they can feel sexual pleasure is from the hard, fast strokes after insertion that build to the climax. The partners of these men may not realize that their men are getting pleasure from sex the only way they can. Thus they may blame their men for not approaching sexual intimacy differently. It appears that circumcision can harm not only men, but their partners as well. The mistaken belief that a circumcised penis is more hygienic or more aesthetically pleasing may have contributed to the alarming rates of sexual dissatisfaction in the U.S. todayboth for men and their partners.
9 October 1998
Revised 4 Sept 2003
Since writing this monograph, I have stumbled onto some additional studies that relate to this paper.
This study, a histological study of the nerves of the penis, revealed that the foreskin is densely populated with fine touch receptors. These are specialized receptors that respond to the lightest touch. They are present in the most sensitive parts of the body, including the fingers, lips, tongue, and eyes. These nerves are exquisitely sensitive to the gliding or rolling action of the foreskin, and are easily over-stimulated, which explains why intact men and restored men find that any stimulation of mucosal membranes except by other mucosal membranes can be unpleasant or even painful.
This study illustrates the sensitivity loss caused by keratinization. It found that penile sensitivity of intact males is 25-30% greater than that of circumcised males.
Note: The large increase of glans sensitivity experienced by some men who restore is due to the shedding of layers of keratinized tissue formed to protect the glans. This renewed sensitivity may also make the strong stimulation that was needed previously more painful than pleasurable.
This article is a survey of women who have experienced sex with both normal and circumcised men. The study found that women preferred sex with intact men. Women stated that they felt more intimacy with noncircumcised partners, that they were more likely to experience orgasm with them, that they felt less vaginal discomfort, and that the sexual experience as a whole was more satisfying. This important study might explain why there is so much sexual dissatisfaction and frustration in the U.S. today, where nearly 60-90% of adult men (depending on their birthdate) are circumcised.
Premature ejaculation seems to be the most common male sexual dysfunction worldwide. Reports from the Middle East, India and Asia show a much higher incidence of premature ejaculation than in the western world. In these areas the vast majority of men have had a ritual circumcision. This study investigated penile sensitivity with TSA 2001 Thermal Analyzer (cold/warm and tactile sensation) in normal men and in men with premature ejaculation, in circumcised and non-circumcised men.