The Sexual Response Cycle: Sexual Hormones - Essay Example

?Sexual hormones play a number of roles in the human body, upon conception they play a role in determining the sex of the embryo as well as later in life estrogen levels, help regulate menstruation and ovulation in females. In humans the sexual response cycle is much more complex where psychological and physiological factors play a major role, although human sex hormones do play an organizing and activating effects (Buchanan, 1992, pg. 439). Human sex hormones play also a vital part in the sexual behavior and response cycle of both sexes since levels of testosterone (male human hormone) have direct effects on both sexes by stimulating sex drive and facilitating response to sexual stimuli an activating effect. According to Masters and Johnson (1966) the sexual response cycle or the biological response of sexual stimuli can be very similar between males and females. There are a number of similarities as well as differences in the human sexual response cycle in both males and females. Both males and females go through four distinct phases in their sexual response cycle, although the specific timing and physiological response to each phase is different between the sexes. In both males and females the sexual response cycle is characterized by two physical responses myotonia and vasocongestion. Myotonia is muscle tension which causes spasms of the feet, hands, face as well as the sexual organs. Vasocongestion is swelling of the tissues of the genitals caused by the engorging of tissues with blood. The researchers divided the cycle in four distinct phases: excitement, plateau, orgasm and resolution. Excitement phase- This is the first phase of the sexual response cycle it’s the phase when we start to feel arousal. It is characterized in males by erection of the penis which is caused by blood rushing to the spongy tissues of the penis shaft; it can cause an erection in as little as 3-8 seconds on a healthy young male. The skin of the scrotum also thickens due to the same automatic physiological response and the testes will elevate. For the females, the excitement phase is marked by the vaginal lubrication which may start from 10-30 seconds after stimulation. The size of the clitoris will increase while simultaneously spreading and flattening of the vaginal lips due to vasocongestion. The inner two-thirds of the vagina will also expand, as well as turning a deeper hue. Also the breasts will get larger, and the as the blood vessels near the surface of the skin will become more pronounced. In both sexes, overall blood pressure will increase causing the skin to become flushed especially in females, the heart rate will speed up, earlobes will increase in size and the nipples may become hard and erect. Plateau phase- This second phase of the sexual response cycle is characterized by a somewhat stable level of arousal. In the male, the tip of the penis shaft will increase in size and turn a purplish hue due to increased vasocongestion and seminal fluid can start leaking from the tip of the penis before ejaculation. In addition the testes can reach up to 1.5 times their original size and continue to elevate into the body cavity to reach the ideal position for ejaculation. For women, the inner two-thirds of the vaginal opening will fully expand, with a corresponding thickening of the outer one-third of the vagina. The clitoris of the female will retract inside its hood and become shorter in size. For both sexes breathing will become much more rapid and shallow, the blood pressure will continue to increase and heartbeat can reach anywhere from 100-160 beats per minute, depending on the individual. Orgasmic Phase- The third phase is the most intense of the sexual response cycle. In the male, this stage is characterized by two phases of muscular contractions prior to ejaculation. The first stage semen is collected at the phase of the penis. In the second stage the contractions expel the semen out of the shaft of the penis. Typically, the first set of 3-4 contractions which are the strongest, occur at approximate intervals of .8 seconds, followed by 2-4 weaker contractions which finalize the release of sexual tension. The strength and duration of the contractions as well as the amount of semen in the scrotum determine the duration and strength of the orgasm. For the women just like in the male, orgasmic contractions come in two stages. A total series of 3-15 contractions will be produced during orgasm; the first few contractions are the strongest and produce the release of sexual tension as in the males, with the following contractions being much weaker. For both sexes, heart rate and blood pressure will peak, with the heart reaching up to180 beats per minute. Resolution Phase- For both males and females after the orgasm the body will return to its pre aroused state, unless additional sexual stimulation is introduced. For males blood is drained from the engorged penis and testes, so the erection of the penis is eliminated and testes returning to normal size. Unlike women, men enter a refractory period which prerequisites the male anywhere from 10 minutes to up to a day for older gentlemen before they can have another orgasm. In females blood is drained from the engorged areas of the vagina, clitoris and labia returning to pre aroused state. For both sexes blood pressure, heart rate and respiration return to normal rates. There are a variety of sexual dysfunctions that an individual can suffer. According to the National Health and Social Life Survey, women have a higher rate of problems such as lack of pleasure during sex, painful sex or inability to reach orgasm. In the case of Hypoactive Sexual Disorder females report a lack of sexual desire, drive and a general lack of sexual fantasies. A number of women suffer from failure to get sexually aroused and lack the necessary lubrication, which is called Female Sexual Arousal Disorder. In males, the inability to sustain an erection is called male erectile disorder, which can be quite common in older males. In the case of Orgasmic Disorder both men and women that although they are sexually excited yet cannot reach the orgasmic phase. In males Premature Ejaculation arises when a male ejaculates with almost no sexual stimulation. The causes of sexual dysfunctions are varied, but they fall into two categories, physical and physiological. Diseases such as diabetes, multiple sclerosis, hormonal problems, spinal cord injury among other physiological can all play a part in sexual dysfunctions in general. References Buchanan, C.M., Eccles, J.S., Becker, J.B. (1992). Are adolescents the victims of raging hormones: evidence for activational effects of hormones on moods and behavior at adolescence. Psychological Bulletin, 111:62-107. Masters, W.H.; Johnson, V.E. (1996). Human Sexual Response. Toronto; New York: Bantam Books. Read More