Ethnicity, Religion, and Circumcision
—’ he practice of male circumcision has been the most commonly performed operation in the United States for over 40 years (Laumann et al., 2000). Nonreligious circumcision became popular in the 1870s because it was thought to promote hygiene, reduce "unnatural" sexual behaviors (G. Kaplan, 1977), prevent syphilis and gonorrhea, and reduce masturbation (Wallerstein, 1980). An article published in 1947 supporting circumcision reported that cancer was more common in laboratory mice who were not circumcised (Plaut & Kohn-Speyer, 1947). All of these medical reports and social considerations have influenced the incidence of male circumcision.
There have been some differences in circumcision rates across religious groups in the United States (Laumann et al.,
2000) . For example, Jewish men have the highest rates of circumcision, whereas Protestant men have the lowest rates. Ethnicity is also related to some small differences in circumcision rates. Caucasian men are more likely than African American or Hispanic men to be circumcised. Various ethnic groups have different preferences concerning circumcising their male children. If circumcision is less common in a particular ethnic group, parents will not circumcise their male children so their sons will look like other boys (Laumann et al.,
2000) . These social considerations have been found to outweigh the medical facts when parents are deciding whether to circumcise their sons (M. S. Brown & Brown, 1987).
The Root The root of the penis enters the body just below the pubic bone and is attached to internal pelvic muscles (see Figure 5.2). The root of the penis goes further into the body than most men realize; it can be felt in the perineum (between the scrotum and anus), particularly when the penis is erect.
Question: Why do men so often wake up with erections?
Men ‘s penises (and women’s clitorises) become erect during a part of sleep known as the REM (rapid eye movement) cycle. Some physiologists have suggested that nighttime erections help keep the cells of the penis supplied with blood. Both men and women typically enter REM sleep many times each night, and often we are in a REM cycle right before we wake up. That is why men often awaken with an erection. Some men believe that having a full bladder makes the morning erection firmer and longer lasting, though there is little medical evidence for this. Because men have no control over nighttime erections, physicians often ask men who have problems getting erections if they experience erections in their sleep, which can indicate whether their problem is physiological or psychological. We will discuss this more in Chapter 14.
Erection Erection can occur with any form of stimulation the individual perceives as sexual—visual, tactile, auditory, olfactory, or cognitive. Excitement causes nerve fibers to swell the arteries of the penis, allowing blood to rush into the corpora cavernosa and corpus spongiosum, while veins are compressed to prevent the blood from escaping. The erectile tissues thus will fill with blood, and the penis becomes erect. The penis returns to its flaccid state when the arteries constrict, the pressure closing off the veins is released, and the sequestered blood is allowed to drain.
Erection is basically a spinal reflex, and men who have spinal injuries can sometimes achieve reflex erections, in which their penis becomes erect even though they can feel no sensation there. These erections generally occur without cognitive or emotional excitement (see Chapter 14). Also, as we mentioned earlier, most men have regular erections during their sleeping cycle and often wake up with erections, which shows that conscious sexual excitement is not necessary for erection.