Orgasm
Orgasm, sexual climax, or simply climax, is the sudden release of accumulated sexual excitement during the sexual response cycle, characterized by intense sexual pleasure resulting in rhythmic, involuntary muscular contractions in the pelvic region. Orgasms are controlled by the involuntary or autonomic nervous system and are experienced by both males and females; the body's response includes muscular spasms, a general euphoric sensation, and, frequently, body movements and vocalizations. The period after orgasm is typically a relaxing experience due to the release of the neurohormones oxytocin and prolactin, as well as endorphins.
Human orgasms usually result from physical sexual stimulation of the penis in males and of the clitoris in females. Sexual stimulation can be by masturbation or with a sexual partner. Physical stimulation is not a requisite, as it is possible to reach orgasm through psychological means. Getting to orgasm may be difficult without a suitable psychological state. During sleep, a sex dream can trigger an orgasm and the release of sexual fluids.
The health effects surrounding the human orgasm are diverse. There are many physiological responses during sexual activity, including a relaxed state, as well as changes in the central nervous system, such as a temporary decrease in the metabolic activity of large parts of the cerebral cortex, while there is no change or increased metabolic activity in the limbic areas of the brain. There are sexual dysfunctions involving orgasm, such as anorgasmia.
The importance of reaching orgasm for sex to be satisfying varies between individuals, and theories about the biological and evolutionary functions of orgasm differ.
Definitions
In a clinical context, orgasm is usually defined strictly by the muscular contractions involved during sexual activity, along with the characteristic patterns of change in heart rate, blood pressure, and often respiration rate and depth. This is categorized as the sudden discharge of accumulated sexual tension during the sexual response cycle, resulting in rhythmic muscular contractions in the pelvic region. Definitions of orgasm vary, and at least 26 definitions of orgasm are listed in the 2001 journal Clinical Psychology Review.There is some debate about whether certain types of sexual sensations should be accurately classified as orgasms, including female orgasms caused by G-spot stimulation alone, and the demonstration of extended or continuous orgasms lasting several minutes or even an hour. The question centers around the clinical definition of orgasm, but this way of viewing orgasm is merely physiological, while there are also psychological, endocrinological, and neurological definitions of orgasm. In these and similar cases, the sensations experienced are subjective and do not necessarily involve the involuntary contractions characteristic of orgasm. In both sexes, they are extremely pleasurable and often felt throughout the body, causing a mental state that is often described as transcendental, and with vasocongestion and associated pleasure comparable to that of a full-contractionary orgasm. For example, modern findings support the distinction between ejaculation and male orgasm. For this reason, there are views on both sides as to whether these can be accurately defined as orgasms.
Achievement
Orgasms can be achieved during a variety of activities, including vaginal, anal, oral, manual, and non-penetrative sex, or masturbation. They may also be achieved by the use of a sex toy or an erotic electrostimulation. Achieving orgasm by stimulation of the nipples or other erogenous zones is rarer. Multiple orgasms are also possible, especially in women, but they are also uncommon.In addition to physical stimulation, orgasm can be achieved from psychological arousal alone, such as during dreaming or by forced orgasm. Orgasm by psychological stimulation alone was first reported among people who had spinal cord injuries. Although sexual function and sexuality after spinal cord injury are very often impacted, this injury does not deprive one of sexual feelings such as sexual arousal and erotic desires.
Scientific literature focuses on the psychology of female orgasm significantly more than it does on the psychology of male orgasm, which "appears to reflect the assumption that female orgasm is psychologically more complex than male orgasm," but "the limited empirical evidence available suggests that male and female orgasm may bear more similarities than differences. In one controlled study by Vance and Wagner, independent raters could not differentiate written descriptions of male versus female orgasm experiences".
Female
Factors and variability
In women, the most common way to achieve orgasm is by direct sexual stimulation of the clitoris. General statistics indicate that 70–80 percent of women require direct clitoral stimulation to achieve orgasm, although indirect clitoral stimulation may also be sufficient. The Mayo Clinic states, "Orgasms vary in intensity, and women vary in the frequency of their orgasms and the amount of stimulation necessary to trigger an orgasm." Clitoral orgasms are easier to achieve because the glans of the clitoris, or clitoris as a whole, has more than 8,000 sensory nerve endings, which is as many nerve endings as are present in the human penis or glans penis. As the clitoris is homologous to the penis, it is equivalent in its capacity to receive sexual stimulation.One misconception, particularly in older research publications, is that the vagina is completely insensitive. In reality, there are areas in the anterior vaginal wall and between the top junction of the labia minora and the urethra that are especially sensitive. With regard to specific density of nerve endings, while the area commonly described as the G-spot may produce an orgasm, and the urethral sponge runs along the "roof" of the vagina and can create pleasurable sensations when stimulated, intense sexual pleasure from vaginal stimulation is occasional or otherwise absent because the vagina has significantly fewer nerve endings than the clitoris. The greatest concentration of vaginal nerve endings are at the lower third of the vagina.
Sex educator Rebecca Chalker states that only one part of the clitoris, the urethral sponge, is in contact with the penis, fingers, or a dildo in the vagina. Hite and Chalker state that the tip of the clitoris and the inner lips, which are also very sensitive, are not receiving direct stimulation during penetrative intercourse. Because of this, some couples may engage in the woman on top position or the coital alignment technique to maximize clitoral stimulation. For some women, the clitoris is very sensitive after climax, making additional stimulation initially painful.
Masters and Johnson argue that all women are potentially multiply orgasmic, but that multiply orgasmic men are rare, and stated that "the female is capable of rapid return to orgasm immediately following an orgasmic experience, if re-stimulated before tensions have dropped below plateau phase response levels". Though it is generally reported that women do not experience a refractory period and thus can experience an additional orgasm, or multiple orgasms, soon after the first one, some sources state that both men and women experience a refractory period because women may also experience a period after orgasm in which further sexual stimulation does not produce excitement. After the initial orgasm, subsequent orgasms for women may be stronger or more pleasurable as the stimulation accumulates.
Clitoral and vaginal categories
Discussions of female orgasm are complicated by orgasms in women typically being divided into two categories: clitoral orgasm and vaginal orgasm. In 1973, Irving Singer theorized that there are three types of female orgasms; he categorized these as vulval, uterine, and blended, but because he was a philosopher, "these categories were generated from descriptions of orgasm in literature rather than laboratory studies." In 1982, Ladas, Whipple and Perry also proposed three categories: the tenting type, the A-frame type, and the blended type. In 1999, Whipple and Komisaruk proposed cervix stimulation as being able to cause a fourth type of female orgasm.Female orgasms by means other than clitoral or vaginal/G-spot stimulation are less prevalent in scientific literature, and most scientists contend that no distinction should be made between "types" of female orgasm. This distinction began with Sigmund Freud, who postulated the concept of "vaginal orgasm" as separate from clitoral orgasm. In 1905, Freud stated that clitoral orgasms are purely an adolescent phenomenon and that upon reaching puberty, the proper response of mature women is a change-over to vaginal orgasms, meaning orgasms without any clitoral stimulation. While Freud provided no evidence for this basic assumption, the consequences of this theory were considerable. Many women felt inadequate when they could not achieve orgasm via vaginal intercourse alone, involving little or no clitoral stimulation, as Freud's theory made penile–vaginal intercourse the central component to women's sexual satisfaction.
The first major national surveys of sexual behavior in the U.S. were the Kinsey Reports. Alfred Kinsey was the first researcher to harshly criticize Freud's ideas about female sexuality and orgasm when, through his interviews with thousands of women, Kinsey found that most of the women he surveyed could not have vaginal orgasms. He "criticized Freud and other theorists for projecting male constructs of sexuality onto women" and "viewed the clitoris as the main center of sexual response" and the vagina as "relatively unimportant" for sexual satisfaction, relaying that "few women inserted fingers or objects into their vaginas when they masturbated." He "concluded that satisfaction from penile penetration mainly psychological or perhaps the result of referred sensation".
Masters and Johnson's research into the female sexual response cycle, as well as Shere Hite's, generally supported Kinsey's findings about female orgasm. Masters and Johnson's research on the topic came at the time of the second-wave feminist movement and inspired feminists such as Anne Koedt, author of The Myth of the Vaginal Orgasm, to speak about the "false distinction" made between clitoral and vaginal orgasms and women's biology not being properly analyzed.