Sexual Responce Cycle
The changes and responses that occur in the body of both men and women when sexually aroused are referred to as the sexual response cycle. The sexual response cycle is divided into four separate phases which include excitement, plateau, orgasm, and resolution. These changes are similar for both men and women. According to Nevid and Rathus (2005), each phase is characterized by vasocongestion and myotonia. Vasocongestion is the swelling of the genital tissues with blood, and myotonia is the muscle tension associated with sexual arousal. Although the changes are similar, there are some differences in the way these changes affect men and women.
During the excitement phase, vasocongestion in males causes erection after less than 10 seconds of sexual stimulation. The scrotal skin thickens and the testes increase in size and become elevated during this phase. For the female, vasocongestion causes vaginal lubrication, the clitoris to swell, flattens and spreads the vaginal lips, causes the inner part of the vagina to expand, the breasts enlarge, and the blood vessels become more prominent. Commonalities in this phase include rosy sex flush in the skin, erection of the nipples, and myotonia causes an increase in heart and blood pressure in both men and women.
During the plateau phase, sexual arousal remains stable. In males, vasocongestion causes the head of the penis to increase in circumference and takes on a purplish hue. Also in this phase, vasocongestion causes testes to enlarge to one and a half times the normal size and elevates the testes to prepare for ejaculation. In women, vasocongestion causes the outer part of the vagina to swell, the contraction of the vaginal opening, the expansion of the inner part of the vagina, and also causes the clitoris to shorten and withdraw beneath the clitoral hood. Commonalities for both male and females in this phase include rapid breathing, and increase in heart rate and blood pressure caused by myotonia.
During the excitement phase, vasocongestion in males causes erection after less than 10 seconds of sexual stimulation. The scrotal skin thickens and the testes increase in size and become elevated during this phase. For the female, vasocongestion causes vaginal lubrication, the clitoris to swell, flattens and spreads the vaginal lips, causes the inner part of the vagina to expand, the breasts enlarge, and the blood vessels become more prominent. Commonalities in this phase include rosy sex flush in the skin, erection of the nipples, and myotonia causes an increase in heart and blood pressure in both men and women.
During the plateau phase, sexual arousal remains stable. In males, vasocongestion causes the head of the penis to increase in circumference and takes on a purplish hue. Also in this phase, vasocongestion causes testes to enlarge to one and a half times the normal size and elevates the testes to prepare for ejaculation. In women, vasocongestion causes the outer part of the vagina to swell, the contraction of the vaginal opening, the expansion of the inner part of the vagina, and also causes the clitoris to shorten and withdraw beneath the clitoral hood. Commonalities for both male and females in this phase include rapid breathing, and increase in heart rate and blood pressure caused by myotonia.
References: Nevid, J.S. & Rathus, S.A. (2005). Psychology and the challenges of life: Adjustment in the new millennium. Hoboken, NJ: John Wiley & Sons.