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2vol 21 no x month 2008
O
rgasm is a compelling, brief event
that is an integration of cognitive,
emotional, somatic, visceral, and
neural processes. Modern definitions of
orgasm recognise and incorporate all these
levels (see Komisaruk et al., 2006).
Despite bodily differences and some
different neural events at orgasm, women’s
and men’s descriptions
of the basic feeling of
orgasm are
indistinguishable from
each other (Vance &
Wagner, 1976). The
scientific study of
orgasm in humans was
initially focused on
measurement of such
somatic and visceral
events, as exemplified by
the pioneering studies of
Masters and Johnson
(1966) in men and
women.
In recent decades
orgasm research has entered a new era. The
widespread use of antidepressants and
antipsychotics, and their significant and
mainly untoward effects on sexual
responses and orgasm in humans, has
provided clues not only to the
neurotransmitter bases of orgasm but also
to the development of new drugs that can
avoid those side-effects (Komisaruk et al.,
2006). Furthermore, new technology such
as fMRI and PET has been applied to the
study of orgasm, enabling us to begin to
identify the underlying brain systems
towards understanding its compelling
nature.
Drugs and orgasm
Psychotropic medications commonly
produce anorgasmia as a side-effect. Most
of these drugs – antidepressants and
antipsychotics – either (a) interfere with the
binding or action of dopamine at its D2 or
D4 receptors, respectively (Stahl, 1999), or
(b) raise the levels of serotonin in some
synapses by inhibiting its reuptake.
Dopamine – an orgasm ‘accelerator’
Abundant evidence points to dopamine as
the key neurotransmitter involved in
stimulating
orgasm in
humans. Thus,
administration
of the
dopamine
precursor L-
dopa,
dopaminergic
agonists (e.g.
apomorphine),
dopamine
releasers (e.g.
amphetamine),
or dopamine
reuptake
inhibitors (e.g.
cocaine or bupropion) facilitate the
expression of orgasm in men and women.
Conversely, administration of
antipsychotics impair orgasm, by blocking
postsynaptic dopamine receptors (see
Komisaruk et al., 2006)
Dopamine-synthesising neurons that
originate in the lower brainstem
(specifically the ventral tegmental area) are
activated during ejaculation in men, as
measured by PET imaging (Holstege et al.,
Aron, A., Fisher, H., Mashek, D.J., Strong,
G., Li, H. & Brown, L.L. (2005).
Reward, motivation, and emotion
systems associated with early-stage
intense romantic love. Journal of
Neurophysiology, 94, 327–337.
Bancroft, J. (1984). Hormones and
human sexual behavior. Journal of
Sex and Marital Therapy, 10, 3–21.
Bellerose, S.B. & Binik, Y.M. (1993). Body
image and sexuality in
oophorectomized women. Archives of
Sexual Behavior, 22, 435–459.
Belzer, E., Whipple, B. & Moger, W.
(1984). On ejaculation. The Journal of
Sex Research, 20, 403–406.
Bowers, M.B., Van Woert, M. & Davis, L.
(1971). Sexual behavior during L-
dopa treatment for parkinsonism.
American Journal of Psychiatry, 127,
1691–1693.
Braunstein, G.D., Sundwall, D.A., Katz,
M., Shifren et al. (2005). Safety and
efficacy of a testosterone patch for
the treatment of hypoactive sexual
desire disorder in surgically
menopausal women. Archives of
Internal Medicine, 165, 1582–1589.
Carmichael, M.S., Warburton, V.L., Dixen,
J. & Davidson, J.M. (1994).
Relationships among cardiovascular,
muscular, and oxytocin responses
during human sexual activity.
Archives of Sexual Behavior, 23, 59–79.
Casey, K.L., Morrow, T.J., Lorenz, J. &
Minoshima, S. (2001). Temporal and
spatial dynamics of human forebrain
activity during heat pain: Analysis by
positron emission tomography.
Journal of Neurophysiology, 85,
951–959.
Chuang, Y-C., Lin, T-K., Lui, C-C. et al.
(2004). Tooth-brushing epilepsy with
ictal orgasms. Seizure, 13, 179–182.
references
Orgasm
Barry R. Komisaruk, Carlos Beyer and Beverly Whipple view the subject
of orgasms as an experience that is an integration of body, nervous system
and the mind
Why should recent findings about
orgasm be of interest to psychologists?
If psychologists are interested in the
bases of pleasure and pain – in altered
states of consciousness, in
psychological side-effects of
antidepressant and antipsychotic
drugs, in some surprising effects of sex
hormones, in psychological effects of
surgery of the sexual/reproductive
system, or in the function of the unique
phenomenon of orgasm, then the
following brief update may engage and
inform you.
resources question
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ARTICLE
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read discuss contribute at www.thepsychologist.org.uk 3
orgasm
2003). A major projection of the dopamine
neuron axon terminals is to the nucleus
accumbens of the forebrain. This nucleus is
activated during orgasm in women, as
measured by fMRI (Komisaruk et al.,
2004).
Thus, activation of the dopaminergic
system of the brain evidently participates in
the production of orgasm in women and
men, on the basis of pharmacological
functional brain imaging, and
neuroanatomical studies. Consistent with
this role of dopamine, hypersexuality has
been reported in cases of Parkinsonism that
is treated with dopamine precursor or
agonist drugs (Bowers et al., 1971). Acute
administration of drugs that increase
dopaminergic activity only occasionally
induces orgasm in the absence of other
factors. However, intravenous injection of
cocaine, which rapidly increases the release
of dopamine at its neuronal terminals in
the forebrain, can induce the ‘cocaine rush’
that individuals report as feeling similar to
genital orgasm (Miller & Gold, 1988).
Serotonin – an orgasm ‘brake’
Antidepressive drugs (e.g. the SSRIs, which
increase the accumulation of serotonin in
synapses by blocking its reuptake into the
neuron terminals from which it was
released) tend to produce anorgasmia.
Inhibition of orgasm is mediated by
interaction of serotonin with the serotonin-
2 receptor subtype (Haensel et al., 1995).
This molecular process is critically involved
in the inhibition of orgasm – agents such as
cyproheptadine that block the action of
serotonin almost immediately counteract
the inhibitory effect of antidepressants on
orgasm.
The ‘exception that proves the rule’ is
found in the case of nefazodone, which,
unlike the other SSRIs, does not inhibit
orgasm. Nefazodone, in addition to
blocking the reuptake of serotonin, also
blocks the serotonin-2 receptors, thereby
counteracting the effect
of the elevated synaptic
levels of serotonin, and
thus preventing the
serotonin from
inhibiting orgasm (Stahl,
1999). Conversely,
buspirone, which
decreases the release of
serotonin into the
synapse, facilitates
orgasm, thus further
supporting the serotonin
brake concept.
The braking effect of
serotonin on sexual
response is reported to be used ‘off-label’,
to therapeutic advantage, by treating
premature ejaculation with SSRI
antidepressants.
The role of sex hormones
By contrast with the action of
neurotransmitters, which change neuronal
excitability almost immediately upon their
release into synapses and thereby generate
orgasm, the sex hormones – oestrogens and
androgens – characteristically act with
latencies of days – providing a facilitatory
background for orgasm. In men, a
deficiency of sex steroids (e.g. resulting
from ageing or following surgical removal
of the testes) may lead to anorgasmia and a
decrease in sexual interest. The role of sex
hormones in women is not as clear. Early
studies concluded that bilateral
oöphorectomy (i.e. removal of both
ovaries) rarely resulted in lack of desire or
anorgasmia. However, more recent studies
report decreases in sexual drive and
pleasure after oöphorectomy (e.g.
Braunstein et al., 2005).
Oestrogen (oestradiol) treatment does
not correct these effects, because they are
most likely due to a decrease in plasma
levels of testosterone resulting from a
decrease in the androgen secretion that
normally occurs from the ovaries.
Treatment with testosterone, alone or in
combination with oestradiol, restores
sexual interest and pleasure (orgasm
frequency) in most of these women
(Bellerose & Binik, 1993).
Androgen (testosterone) therapy is the
standard treatment for hypogonadal men
complaining of anorgasmia (Steidle et al.,
2003). Transdermal testosterone patches or
gels, which slowly and steadily release the
androgen into the circulation, have recently
been used successfully. But while the
efficacy of testosterone to improve sexual
behaviour in hypogonadal men is
incontrovertible, supplemental dosing with
testosterone does not increase the
frequency or quality of orgasms in men
whose androgen levels are ‘normal’
(O’Connor et al., 2004).
Hormones are not only stimulatory to
sexual desire and orgasm. These
components of sexual response are
depressed by prolactin, a protein hormone
produced by the anterior pituitary gland
that is released at orgasm in men and
women. Men and women with
hyperprolactinemia – elevated blood levels
of prolactin – typically show anorgasmia
and a low level of sexual desire (Bancroft,
Goetsch, M.F. (2005). The effect of total
hysterectomy on specific sexual
sensations. American Journal of
Obstetrics and Gynecology, 192,
1922–1927.
Haensel, S.M., Rowland, D.L. & Slob, A.
K. (1995). Serotonergic drugs and
masculine sexual behavior in
laboratory rats and men. In J.
Bancroft (Ed.) The pharmacology of
sexual function and dysfunction.
Amsterdam: Excerpta Medica.
Holstege, G., Georgiadis, J.R., Paans, A.
M.J. et al. (2003). Brain activation
during human male ejaculation.
Journal of Neuroscience, 23,
9185–9193.
Janszky, J., Ebner, A., Szupera, Z. et al.
(2004). Orgasmic aura – A report of
seven cases. Seizure, 13, 441–444.
Kinsey, A., Pomeroy, W., Martin, C. &
Gebhard, P. (1953). Sexual behavior in
the human female. Philadelphia: W.B.
Saunders.
Koeman, M., van Driel, M.F., Weijmar et
al. (1996). Orgasm after radical
prostatectomy. British Journal of
Urology, 77, 861–864.
Komisaruk, B.R., Beyer-Flores, C. &
Whipple, B. (2006). The science of
orgasm. Baltimore, MD: Johns
Hopkins University Press.
Komisaruk, B., Whipple, B. Crawford, A.
et al. (2004). Brain activation during
vaginocervical self-stimulation and
orgasm in women with complete
spinal cord injury. Brain Research,
1024, 77–88.
Krüger, T.H., Hartmann, U. &
Schedlowski, M. (2005).
Prolactinergic and dopaminergic
mechanisms underlying sexual
arousal and orgasm in humans.
World Journal of Urology, 23, 130–138.
The little death
Kinsey et al. (1953, p.613) mention, and provide numerous
references to the observation that ‘at orgasm, some
individuals may remain unconscious for a matter of
seconds or even for some minutes’. They point out that
this phenomenon has been described as ‘petit mort’
(little death), and ‘la mort douce’ (the sweet death). While
the underlying mechanism is not known, some have
suggested contributing factors to be hyperventilation,
insufficient blood flow to the brain resulting from
irregular heartbeat and/or low blood pressure (Mann et
al., 1982), and aortic constriction (Needles, 1973).
4vol 21 no x month 2008
orgasm
1984).
Indeed, it has been proposed that some
antidepressant (serotoninergic) and
neuroleptic (anti-dopaminergic) drugs
depress orgasm by elevating prolactin
secretion. Moreover, some evidence,
admittedly inconclusive, suggests a role of
the prolactin released during orgasm in the
production of the characteristic
(‘refractory’) periods of sexual
inactivity following ejaculation
in men. In one case, a man
who did not show prolactin
release during ejaculation had
three experiences of vaginal
intercourse with ejaculatory
orgasm without intervening
refractory periods (Krüger et
al., 2005).
Brain imaging of
orgasm
Consistent with the above-
described role of dopamine in
facilitating orgasm, several
brain-imaging studies provide evidence that
the dopaminergic ‘reward’ system is
activated during sexual arousal and orgasm.
This is supported by our fMRI studies
showing that the nucleus accumbens
region, which receives dopamine-
containing axon terminals from neurons
that originate in the ventral midbrain, is
activated during orgasm in women
(Komisaruk et al., 2004). Consistent with
these findings, Holstege et al. (2003), using
PET, found that the ventral midbrain area,
in which the dopamine neurons originate,
is activated in men during orgasm. In fMRI
studies, Aron et al. (2005) found that men
and women who were ‘intensely in love’,
when observing pictures of their beloved,
showed activation in this ventral midbrain
area and the caudate nucleus to which the
dopamine-containing neurons also project.
We have reported that in women, pain
thresholds are more than doubled during
orgasm (Whipple & Komisaruk, 1985),
and that the insular cortex and anterior
cingulate cortex in the forebrain are
activated during orgasm (Komisaruk et al.,
2004). Other investigators report that these
cortical regions are activated during painful
stimulation (Casey et al., 2001). These
findings, considered together, suggest that a
significant
(active
inhibitory) interaction occurs between
orgasm and pain in the insular and anterior
cingulate cortices, indicating that they are
involved in both pain and pleasure.
Could these brain regions have some
property that is common to both pain and
pleasure, perhaps intense emotional
expression – controlling the contorted
facial expression that occurs both during
painful anguish and similarly during
impending orgasm – separate from the
actual different feelings of pain versus
pleasure? Furthermore, it seems possible
that (at least female) genital stimulation
and orgasm, which we have shown
attenuates the aversive component of pain,
nevertheless may not attenuate the arousing
quality of pain. This might help account for
the practice of receiving what would
appear to be pain-inducing stimulation in a
sexually stimulating context, a combination
that apparently intensifies pleasure.
Another brain component that we have
found to be activated during orgasm in
women is the paraventricular nucleus
region of the hypothalamus (Komisaruk et
al., 2006). The neurons of this nucleus
secrete oxytocin, which is released into the
bloodstream from the posterior lobe of the
pituitary gland in peak amounts at orgasm
in men and women (Carmichael et al.,
1994). These neurons are activated in
response to the vaginal-cervical stimulation
that occurs during both vaginal intercourse
and childbirth, and also to breast and
nipple stimulation during suckling. The
oxytocin released by the sensory
stimulation that originates in these two
different body regions is distributed via the
bloodstream to the uterus and the
mammary glands. At the uterus, the
oxytocin stimulates the contraction of the
smooth muscles, increasing the force of
uterine contractions. This process has been
shown in women to accelerate the
transport of sperm-mimic particles toward
the ovary (left or right side) that has
released a ripe ovum during that particular
ovarian cycle. The finding that women who
were pregnant were previously more likely
to have shown this selectively directional
transport, compared with women who
were not pregnant, has led some to
conclude that orgasm, while not essential
to pregnancy, nevertheless probably
facilitates pregnancy (Wildt et al., 1998).
At the mammary glands, the oxytocin
stimulates the contraction of the smooth
muscle ‘myoepithelial’ cells that surround
the milk-producing alveoli, thereby forcibly
ejecting the milk (Komisaruk et al., 2006).
The fact that there is convergence of the
vaginal-cervical and breast-nipple sensory
activity onto the paraventricular nucleus
neurons helps to account for the ability of
stimulation of each of these organs to
produce orgasms, and probably the ability
of breast stimulation to modulate the
Ladas, A., Whipple, B. & Perry, J. (2005)
The G Spot and other discoveries about
human sexuality. New York: Holt.
Mann, S., Millar Craig, M.W., Gould, B.A.
et al. (1982). Cotal blood pressure in
hypertensives: Cephalgia, syncope,
and the effects of beta-blockade.
British Heart Journal, 47, 84–89.
Masters, W. & Johnson, V. (1966). Human
sexual response. Boston: Little,
Brown.
Miller, N.S. & Gold, M.S. (1988). The
human sexual response and alcohol
and drugs. Journal of Substance
Abuse Treatment, 5, 171–177.
Needles, W. (1973) Orgastic loss of
consciousness: Its possible
relationship to Freud’s theoretical
nihilism. International Journal of
Psycho-Analysis, 54, 315–322.
O'Connor, D.B., Archer, J. & Woo, F.C.
(2004). Effects of testosterone on
mood, aggression, and sexual
behavior in young men. Journal of
Clinical Endocrinology and
Metabolism, 89, 2837–2845.
Reading, P.J. & Will, R.G. (1997).
Unwelcome orgasms. Lancet, 350,
1746.
Saini, J., Kuczynski, E., Gretz, H.F. III &
Sills, E.S. (2002). Supracervical
hysterectomy versus total abdominal
hysterectomy: Perceived effects on
sexual function. BMC Women’s
Health, 2, 1–7.
Sipski, M.L., Komisaruk, B., Whipple, B.,
& Alexander, C.J. (1993). Physiologic
responses associated with orgasm in
the spinal cord injured female.
Archives of Physical Medicine and
Rehabilitation, 74, 1270.
Stahl, S.M. (1999). Essential
psychopharmacology. Cambridge:
Cambridge University Press.
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read discuss contribute at www.thepsychologist.org.uk 5
orgasm
pleasurable perceptual effects of vaginal-
cervical stimulation.
Other brain regions reported to be
activated during orgasm, and their
involvement in other, non-orgasmic,
activity, have been reviewed recently and
extensively in Komisaruk et al. (2006).
How does activation of the neurons in
these brain components, such as the
nucleus accumbens ‘reward area’, produce
the pleasurable feelings of orgasm? We do
not know. However, that is but one case of
the ultimate question in neuroscience –
how do neurons produce any conscious
awareness and their uniquely different
perceptual qualities – pleasure, pain, light,
colour, sound, taste, aroma.
Non-genital orgasms
‘Non-genital orgasm’ is not an oxymoron.
Stimulation of pelvic organs – e.g. clitoris,
vagina, cervix, uterus, anus, rectum,
prostate and penis, are reported to produce
orgasmic sensations. Orgasm elicited from
vaginal stimulation has been described as
‘deep, heaving’, orgasm; from cervical
stimulation as a ‘shower of stars’; from
clitoral stimulation as more restricted to the
clitoral region; and from these organs in
combination as ‘blended’, i.e. combining
their qualities (Ladas et al., 2005).
Sensory activity from these organs is
conveyed by a variety of nerves (see
Komisaruk et al., 2006). For example,
pleasurable orgasmic sensations from the
rectum and prostate described by some
men are conveyed by the pelvic and
hypogastric nerves, respectively
(Komisaruk et al., 2006). Orgasmic
sensations during defecation reported in
the case of a man (Van der Schoot & Ypma,
2002) were probably conveyed by the
pelvic nerve. Stimulation of this nerve that
occurs during passage of the fetus through
the vagina during childbirth has been
reported to produce both orgasmic
sensations and the urge to defecate,
indicating a convergence or commonality
of effect of vaginal and rectal sensory
activity. It is probably sensory activity via
the hypogastric nerve that induces
orgasmic sensations from stimulation of the
prostate during anal intercourse in men,
and conversely, prostatectomy has been
reported to diminish orgasmic sensation
(Koeman et al., 1996).
Stimulation of the hypogastric nerve
probably occurs also during uterine
contractions at orgasm and during
stimulation of the G Spot, a component of
which are the Skene’s glands, considered to
be a homologue in women of the prostate
gland. Ejaculation of a fluid (usually 3–5
ml – approximately one teaspoonful) from
the urethra in women, which is chemically
different from urine (Belzer et al., 1984), is
reported to originate from the female
prostate gland (Zaviacic, 1999).
While there is an extensive literature on
the effects of hysterectomy on sexual
response and orgasm, there is considerable
variability in the reported outcomes, some
studies reporting that orgasmic response is
attenuated (Saini et al., 2002), while others
reporting that sexual response may be
improved (Goetsch, 2005). The
discrepancy in the literature is likely related
to the multiple variable factors, including
presenting conditions (e.g. genital pain or
heavy bleeding that is reduced post-
surgery), variability in surgical procedures
(e.g. degree of nerve-sparing), whether the
cervix and/or ovaries are removed or
retained, the criteria for assessing sexual
response (e.g. sexual satisfaction, orgasm
intensity), the type of genital sensory
stimulation that is used to elicit sexual
response (e.g. clitoral and/or vaginal), and
so on.
Orgasmic sensations are reported to be
produced also by stimulation of other body
components. Men and women with spinal
cord injury commonly describe a region of
skin hypersensitivity near the level of the
injury. When this skin is stimulated
inadvertently (e.g. by clothing brushing it)
it feels aversive. However, if the skin region
is stimulated in the ‘right’ way by the ‘right’
person, it can produce orgasmic feelings.
This effect was observed in our laboratory
in the case of a woman with spinal cord
injury whose hypersensitive skin region
was at the neck and shoulder. When she
stimulated the region with a vibrator, she
reported feeling an orgasm and her blood
pressure and heart rate approximately
doubled, responses characteristic of
genitally stimulated orgasms in able-bodied
women (Sipski et al., 1993)
As reviewed in Komisaruk et al. (2006),
there are published reports of orgasms
elicited by stimulation also of lips, hand,
knee and anus occurring during dreaming
sleep, of phantom limbs, from electrical or
chemical stimulation of the septum,
amygdala or thalamus of the brain and of
the spinal cord.
Orgasms have also been described by
men and women when they suffer epileptic
seizures that are triggered by specific
activity (e.g. brushing the teeth: Chuang et
al., 2004), or that occur spontaneously.
While these epileptic orgasms are in some
cases described as ‘unwelcome’ (Reading &
Will, 1997), others describe them as
pleasurable, one woman refusing anti-
epileptic medication for that reason
(Janszky et al., 2004).
We have measured autonomic and
brain activity during orgasms that women
have produced by thought alone. During
the thought orgasms, the magnitude of the
increases in heart rate, blood pressure, pain
threshold, pupil diameter, and brain
regions are similar to those that we observe
during vaginal or cervical self-stimulation-
induced orgasms (Whipple et al., 1992). It
is not surprising that in those cases of
thought-induced orgasms, the specific
genital sensory thalamic and cortical, and
Steidle, C., Schwartz, S., Jocoby, K. et al.
(2003). AA2500 testosterone gel
normalizes androgen levels in aging
males with improvements in body
composition and sexual function.
Journal of Clinical Endocrinology and
Metabolism 88, 2673–2681.
Van der Schoot, D.K.E. & Ypma, A.F.G.V.
(2002). Seminal vesiculectomy to
resolve defecation-induced orgasm.
BJU International, 90, 761–762.
Vance, E.B. & Wagner, N.N. (1976).
Written descriptions of orgasm: A
study of sex differences. Archives of
Sexual Behavior, 5, 87–98.
Whipple, B. &. Komisaruk, B.R. (1985).
Elevation of pain threshold by vaginal
stimulation in women. Pain, 21,
357–367.
Whipple, B., Ogden, G. & Komisaruk, B.R.
(1992). Physiological correlates of
imagery induced orgasm in women.
Archives of Sexual Behavior, 21,
121–133.
Wildt, L., Kissler, S., Licht, P. & Becker,
W. (1998). Sperm transport in the
human female genital tract and its
modulation by oxytocin as assessed
by hysterosalpingoscintigraphy,
hysterotonography,
electrohysterography and Doppler
sonography. Human Reproduction
Update, 4, 655–666.
Zaviacic, M. (1999). The human female
prostate: From vestigial Skene’s
paraurethral glands and ducts to
woman’s functional prostate. Slovakia:
Slovak Academic Press.
specific limb-motoric regions, are not
activated.
Conclusion
We have but scratched the surface of
orgasm’s potential as an entity for analysis
by physiological, pharmacological,
endocrinological, immunological,
evolutionary, cognitive, social neuroscience
and other lenses. It is evident from a
burgeoning literature that the sociocultural
and funding impediments to studying
orgasm scientifically are gradually but
inexorably being breached.
We hope that psychologists will heed
the reports of men and women that they
experience pleasure, and even orgasmic
experiences, from stimulation that has been
considered as unconventional. We hope
that professionals will acknowledge that
there are many ways in which men and
women experience sensual and sexual
pleasure including orgasm, and thus
validate their richly varied sexual
experiences.
6vol 21 no x month 2008
orgasm
IDr Barry R. Komisaruk is
at Rutgers, The State
University of New Jersey,
Newark, NJ, USA. E-mail:
brk@psychology.rutgers.edu
Dr Carlos Beyer is at CIRA,
University of Tlaxcala,
Tlaxcala, Mexico, and Dr
Beverly Whipple is at
Rutgers, The State
University of New Jersey
3
