Researcher Dr Morris Sorrells and others enlisted 159 men from the San Francisco Bay area, 91 of them circumcised, and conducted touch-sensitivity tests, using an instrument that presses with calibrated hairs, on 17-19 different places on their penises. The men could not see where they were being touched.
It was found that the most sensitive part of a circumcised penis was on the scar in the middle underneath. But several places on the foreskin were more sensitive than that while the glans of the uncircumcised penis was more sensitive than in the circumcised.
The paper is summarised here:
ObjectiveTo map the fine-touch pressure thresholds of the adult penis in circumcised and uncircumcised men, and to compare the two populations.
Subjects and methodsAdult male volunteers with no history of penile pathology or diabetes were evaluated with a Semmes-Weinstein monofilament touch-test to map the fine-touch pressure thresholds of the penis. Circumcised and uncircumcised men were compared using mixed models for repeated data, controlling for age, type of underwear worn, time since last ejaculation, ethnicity, country of birth, and level of education.
ResultsThe glans of the uncircumcised men had significantly lower mean ( SEM ) pressure thresholds than that of the circumcised men, at 0.161 (0.078) g ( P = 0.040) when controlled for age, location of measurement, type of underwear worn, and ethnicity. There were significant differences in pressure thresholds by location on the penis ( P < 0.001). The most sensitive location on the circumcised penis was the circumcision scar on the ventral surface. Five locations on the uncircumcised penis that are routinely removed at circumcision had lower pressure thresholds than the ventral scar of the circumcised penis.
ConclusionsThe glans of the circumcised penis is less sensitive to fine touch than the glans of the uncircumcised penis. The transitional region from the external to the internal prepuce is the most sensitive region of the uncircumcised penis and more sensitive than the most sensitive region of the circumcised penis. Circumcision ablates the most sensitive parts of the penis.
Sorrells ML, Snyder JL, Reiss MD, et al. Fine-touch pressure thresholds in the adult penis. BJU International 2007;99:864-9