Penile stimulation

The most important components of the physical erogenous stimulation of the penis during foreplay and intercourse are the sensations from the foreskin, frenulum/frenar band, and glans. These structures each have their own feeling, and each contributes in its own way to the man's total experience of lovemaking. It must be emphasized that emotional excitement is an extremely important component of sexual enjoyment, and intensifies the man's perception of any physical sensations from his penis.
The foreskin has an inner and outer layer. The outer foreskin layer contains nerve endings which respond to gentle touching during the early stages of sexual arousal. This helps to trigger an erection. The nerves of the inner and outer foreskin contribute to the experience of penile stimulation, up to and including orgasm. These receptors are stimulated by stretching, or when the foreskin rolls over the surface of the glans during intercourse or masturbation.
The foreskin contains sensory receptors called Meissner corpuscles. We believe that these nerves, similar to nerve endings in the fingertips, are there to provide pleasure, as well as fine sensory perception. This seems to help a man to enjoy sex longer without ejaculating prematurely, because he can more easily tell when he is approaching the threshold of orgasm.
Stimulation of the frenulum and ridged band results in intense pleasurable feelings during arousal. Sensations from these structures during intercourse or masturbation are thought to be the primary trigger of orgasm in the intact male. Dr. George Denniston writes:
The ridged bands, which are like horseshoes only in that they curve forward underneath toward the point where the frenulum attaches, can be found in several pictures in John's paper. There are some 20 concentric ridged bands which rub over the corona. Each ridge has Meissner's corpuscles, which respond to pressure, and they produce the sexual pleasure which no individual has a right to take away from another individual.
We believe that stimulation of the glans is most significant in the later stages of sexual intercourse, when penetration is deepest and emotions are running at their highest. Sensations from the glans contribute to the quality of the sensual experience. They are also apparently capable of triggering orgasm on their own, as would be the case in a circumcised man.