The sexual response cycle is a Masters and Johnson’s model of sexual response which consists of four stages or phases. This model is founded on the theory that male and female sexual stimulation- their sexual response cycles- are very similar with obvious differences due to physical make up. The four phases are the excitement phase (initial phase for male and female), plateau phase, orgasmic phase, and the resolution phase. The phases fall in sequence from the beginning of stimulation up toward the peak of climax and back down to levels of prior stimulation.
The excitement phase- initial phase of the sexual response cycle- takes place due to stimulation. Sexual arousal takes place during this phase and vasocongestion (engorgement of blood vessels with blood, which swells the genitals and breast during sexual arousal) occurs in both male and females. The vasocongestion can cause erection in men and young men can do so in 3-8 seconds. Also, the skin on the scrotum tightens and draws up. The male testes will swell and become elevated during this phase. In women, vasocongestion occurs causing the vaginal tissue, clitoris, and the area around the opening of the vagina to swell.
Lubrication appears inside the vagina and the inner vagina expands along with the vaginal wall thickening and becoming a deeper color. In both genders there is swelling of the genital area as stated and also myotonia occurs (muscle tension) along with an increased heart rate and blood pressure. In the second phase or plateau phase of the sexual response cycle the level of sexual arousal stays somewhat stable. In men, the tip of the penis may become swollen and turn the color of reddish purple. The testes continue to elevate and get in position to ejaculate.
The penile opening may release droplets of semen prior to ejaculation. In the female, the inner two-thirds of the vaginal wall expand fully and the outer third of the vagina thickens. The clitoris retracts behind it hood as the uterus elevates and increases in size. In both sexes the affects of vasocongestion and myotonia continue to elevate. The orgasmic phase or climax phase is third in the cycle. The male experiences muscular contractions in two stages. The first stage is the male feeling sensations of impending ejaculation lasting 2 to 3 seconds while semen collects at the base of the penis.
The internal sphincter of the urinary bladder prevents urine from mixing with semen. In the second stage, orgasmic contractions propel the semen through the penis and out of the body. The sense of pleasure is thought to be related to the force of the contractions and the amount of seminal fluid released. There are several contractions and the first few are generally the most intense. As the contractions continue they slow down and become less intense. The rates and patterns can vary from man to man. In females the orgasm is manifested by 3 to 15 contractions of the pelvic muscles that surround the vaginal barrel.
As in the male they release sexual tension and the contractions become weaker as they continue. Both male and female orgasms produce feelings of intense pleasure. Muscle spasms occur throughout the body; blood pressure, heart rate, and breathing rate reach a peak in both male and female as well. The resolution phase or final stage in the sexual response cycle is when the body returns to the state it was in prior to arousal following an orgasm. Blood is released from the areas that were engorged, erection disappears, and the testes return to normal size in men.
Women also experience release of blood from engorged areas. Nipples, clitoris , and the vaginal barrel gradually return to their normal size as was before arousal. Women’s’ heart rate, blood pressure, and breathing rate all continue to normal following an orgasm in both men and women. Both male and female may become relaxed and have a feeling of satisfaction. A major difference in men from women in this phase is that men enter a refractory period or a time when they are not responsive to further sexual stimulation. During this period the male cannot experience another orgasm or ejaculate.
The amount of time that the refractory period lasts depends greatly on the age of the male. In young males the period may last only a few minutes, in males that are 50 or older the period may last from a few minutes to an entire day. Women do not experience this refractory period and can become quickly aroused again to the point of having repeated or multiple orgasms if they so desire and if they continue to receive sexual stimulation. Sexual dysfunction can occur in men and women and refers to a problem during any phase of the sexual response cycle that prevents the individual or couple from experiencing satisfaction from sexual activity.
Dysfunction is more common in the early adult years, with the majority of people seeking help during their late 20s and early 30s. It is also common in the geriatric population, which may be related to bad health associated with aging. There are four categories of sexual dysfunction. The first is desire disorders which are the lack of sexual desire or interest in sex. Also, there is the inability to become physically aroused called an arousal disorder. An orgasm disorder is the delay or absence of orgasm or climax during sexual activity.
Lastly is pain disorder which is the experience of pain during intercourse (this condition mostly affects women. ) One of the most common sexual dysfunctions that men suffer from is an inability to achieve an erection or maintain an erection that can be considered suitable for intercourse which is called erectile dysfunction. This directly affects the excitement phase of the sexual response cycle obviously. Treatment for this type of dysfunction is usually medication (e. g. Viagra) or mechanical aids (pumps or implants. ) Another dysfunction that affects men is an inability to control the timing of ejaculation (premature or retarded. This would bring about the resolution phase in the cycle and would most likely leave the partner in a plateau state entering into the resolution phase regrettably. To treat premature ejaculation one would use behavioral techniques and or psychotherapy with a trained counselor. One of the most common problems for women related to sexual dysfunction is the inability to become aroused. This often involves insufficient vaginal lubrication. The inability to become aroused also may be related to anxiety or inadequate stimulation.
Researchers are investigating how blood flow disorders affecting the vagina and clitoris may contribute to arousal problems. This type of sexual dysfunction can be corrected by treating the underlying physical or psychological problems. Education about human anatomy, sexual function and the normal changes associated with aging, as well as sexual behaviors and responses, may help overcome anxieties about sexual function and performance. Hormone replacement therapy may improve certain conditions, such as loss of vaginal lubrication and genital sensation that can create problems with sexual function.