Scientific Insights Regarding the Orgasm

Russell Eisenman
Department of Psychology
University of Texas-Pan American
Edinburg, TX 78539-2999

Several scientific insights about the orgasm are presented. Insights from evolutionary biology and psychology contribute to understanding the orgasm. Important issues are the point of inevitability (which only exists in males), effects of endorphins, differences regarding orgasm for the two sexes, and how the orgasm increases the strength of a relationship.

The orgasm is an extremely important part of life, yet many are ignorant of important aspects. Even textbooks sometimes neglect orgasm. An excellent insight is provided by Komisaru, Beyer, and Whipple (2008), especially with regard to th effects of drugs, and of sex hormones, and findings from brain imaging. I wish to follow up on their work and present here a brief discussion of some additional scientific findings and ideas about the orgasm.
The orgasm is one of the greatest experiences of joy that people can have. Several studies or reports have tried to explain orgasm or sexual arousal, with many of the issues being controversial, since different researchers take different perspectives (Baker & Bellis, 1993, 1995; Bancroft, 1984, 1988, 1989, 2002; Baumeister & Tice, 2001; Brackett, Bloch, & Abae, 1994; Bridges, Critelli, & Loos, 1985; Buss, 2000, 2004; Clifford, 1978; Darling, Davidson, & Cox, 1991; Dantzker & Eisenman, 2003; Davidson & Hoffman, 1986; Dunn & Trost, 1989; Eisenman, 2001a, 200lb, 2003a, 2003b; Eisenman & Dantzker, 2004a, 2004b; Eisenman, Dantzker, & Ellis, 2004; Ferguson, 2004; Hines, 2001; Hyde, 2001; Lederman, Chan, & Roberts-Gray, 2004; Masters & Johnson, 1966; Palmer & Palmer, 2002; Panksepp, 2000; Scholly, Katz, Gascoigne, & Holck, 2005; Shackelford & LeBlanc, 2001; Shackelford, Weekes-Shakelford, LeBlanc, Bleske, Euler, & Hoier, 2000; Tiefer, 2001; Whipple, 1995, 2000; Zaviacic, 2001).
Sexual attitudes and doubt behavior can differ according to gender and ethnicity as Eisenman and Dantzker (2006) found for Hispanics vs. nonHispanics and for males vs. females. Both physiology and environmental learning are important. Thus an ideal, complete understanding would take into account both biology and culture.
But, what is orgasm? It is a build up and release of sexual tension. It is also the physiological changes that go on in the body associated with the release of sexual tension. And, it is psychosocial, since attitudes are involved as well as, in sexual intercourse, interactions with another person. In males, it is associated with ejaculation of seminal fluid. But, the ejaculation is not the orgasm, it is just something that typically occurs at the same time. Probably many people are confused by this fact, and think that ejaculation and orgasm is the same thing, since they typically occur together.

Evolution and Evolutionary Psychology/Biololgy Explanation
In males, the orgasm would seem to be explainable as inducing great pleasure and thus increasing the likelihood that men would want to engage in sexual intercourse and thereby spread their genes into future generations. In females, an evolutionary psychology explanation is less obvious. If women always or usually achieved orgasm via sexual intercourse, then a similar explanation—pleasurable thus increasing the likelihood of spreading one’s genes into future generations–would seem appropriate. But, since women seem to reach orgasm much less in sexual intercourse then men do, it is less clear what the function of the orgasm is for women, from an evolutionary standpoint. Perhaps it is the same as it is for the man, only operating less efficiently in women, i. e., women are less likely to achieve orgasm in intercourse than are men, but they do so enough to make sexual intercourse highly desirable to women (Buss, 2004; Fisher, 1992). Both men and women also can attain orgasm via masturbation, but even here they sometimes fail to achieve orgasm.
Orgasm could also be a signal sent to the other partner, notifying that partner of one’s attractiveness, in a general sense. Sending and receiving signals is very much part of male-female attractiveness communication (Bridgeman, 2003; Buss, 2004; Endler & Basolo, 1998; Fisher, 1992; Gaulin & McBurney, 2001; Grammer, 1996).

Point of Inevitability
In males, the person reaches the point of inevitability, where orgasm is sure to happen. But, in women, there is no such point. A woman can be distracted near the time she might have had an orgasm and will not reach orgasm, whereas the man likely still would reach orgasm, despite the distraction. Further, based on the above citations, orgasm is both a physiological response connected to the brain and spinal cord, and also a function of learning, as well as other physiological responses within the nervous system.

The orgasm releases endorphins, which are responsible for good feelings in people. Endorphins can both give pleasure directly and also decrease any pain a person is feeling. Thus, they are very important brain chemicals. As a Columbia University web site called Go Ask Alice stated:
“Some researchers believe that strenuous exercise releases endorphins into the blood stream. Others agree that endorphins are released during orgasm, as well as during laughter. Endorphins are a group of substances formed within the body that naturally relieve pain. They have a similar chemical structure to morphine. In addition to their analgesic affect, endorphins are thought to be involved in controlling the body’s response to stress, regulating contractions of the intestinal wall, and determining mood. They may also regulate the release of hormones from the pituitary gland, notably growth hormone and the gonadotropin hormones. It seems that endorphin stimulation may occur with frequent sex and masturbation, yet Alice doesn’t know of any evidence at the moment that too much sex (or exercise or laughter, for that matter) and consequential elevated levels of endorphins would have any kind of reverse effect–i.e. depletion of bodily endorphins, depression, etc. As we speak, there is current research being done to elucidate the full range of endorphins’ functions in the body.”

The Orgasm in Women and Men
Many women seldom or never experience orgasm, at least not via sexual intercourse, perhaps seldom or not at all by any means (Lauman, Gagnon, Michael, & Michaels, 1994; Wiederman, 1997). Some males also have problems with orgasm, although to a markedly lesser extent than do females (Rathus, Nevid, & Fichner-Rathus, 2005). Sexual problems, including failure to reach orgasm, can come about for a variety of reasons. It can be due to psychological reasons, e. g., strict religious training in which sex is seen as dirty and bad, or other negative attitudes about sex, or due to physiological reasons, e. g., various illnesses or failure of the physiological system to function properly. Both men and woman have the hormone testosterone in their system, but men have much more than do women. In animals and probably in humans, testosterone is associated with sex and aggression. In some cases, the woman’s testosterone is so low that she has no interest in sex. But, by increasing her testosterone, the sex drive can be restored.

In conclusion, orgasm is a major source of enjoyment for men and women. It is the climax of the sex act for many, and those who do not achieve orgasm often feel they are missing out on full sexual enjoyment. One can, however, enjoy the sex act even without orgasm, so one should not feel like a failure if orgasm is not reached. The orgasm has evolutionary value for men and probably for women in increasing the pleasure of sexual intercourse, and thereby increasing the likelihood that one’s genes will be spread into future generations. The orgasm also likely increases pair bonding between the man and woman, in turn providing two parents for any offspring (or increasing the closeness of homosexual relationships). The orgasm is based on both biology and learning.

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Biographical Note
Russell Eisenman, Ph.D. is Associate Professor of Psychology at University ofTexas-Pan American, Edinburg, TX 78539-2999, USA
Phone: 956 381-3327