3. sexual arousal and response

what is the biggest sex organ?

the brain

low vs high threshold for sexual arousal

doesn’t take much to get them interested in sex

only responsive to really potent sexual cues

limbic system + 3 parts

a set of structures deep within the brain that exerts a profound influence on both animal and human sexual behavior

hypothalamus, hippocampus, amygdala

hypothalamus

controls autonomic processes and sexual responses

medial preoptic area (MPOA) (location + what does dmg to do it do)

in hypothalamus

results in a significant decrease in sexual behavior

hippocampus

assists in learning and memory

amygdala

plays a role in emotion regulation and the processing of social info

nucleus accumbens is also known as…

the pleasure center

In studies of indivs exposed to erotic films during an fMRI scan, male and female participants showed significant activation of the __ and, at least for men, activation of the __as well

amygdala, hypothalamus

cerebral cortex

outer layer of the brain that controls our thoughts, memories, imagination, and use of language

neurotransmitters + 2 the most potent for sexual arousal

substances that transmit signals btwn nerve cells

dopamine, serotonin

dopamine

has the effect of enhancing sexual arousal and increasing the odds of sexual behavior

serotonin

tends to reduce sexual arousal and inhibit orgasm

Research finds that greater sensory impairment is linked to a lower likelihood of both __ and __, but it isn’t necessarily associated w __

initiating sexual activity, being sexually active, sexual satisfaction

primary erogenous zones + examples

portions of the body where nerve endings are present in large quantities

genitals, perineum, nipples, lips, inner thigh

secondary erogenous zones

regions of the body that have taken on sexual significance as a result of conditioning

erotic plasticity

women are suspected to have a less specific genital response pattern than men, which means they demonstrate arousal in response to a wider range of sexual stimuli

3 reasons for the disconnect btwn the subjective and physiological reports of sexual arousal in women in response to visual stimuli

• social pressure either consciously/unconsciously leads women to report lower lvls of sexual interest and arousal than men

• male sexual arousal is more obvious or is easier to detect and interpret than female sexual arousal

• women’s greater genital responsiveness could be a learned behavior — women could be aroused by other women bc they have grown up in a world that has taught them that women are sex objects

the preparation hypothesis

women became genitally responsive to a broad range of sexual cues in order to reduce the risk of injury in the event that sex is forced upon them

pheromones

chemicals secreted by the body that play a role in sexual communication

why are the effects of human pheromones not as dramatic compared to other animal species?

bc we have a less developed sense of smell than most other animal species

vomeronasal organ (VNO)

portion of the olfactory (smell) system that processes pheromones in animals

primary sources of human pheromones

apocrine (sweat) glands in the armpits and pubic region

menstrual synchrony

women eventually start to get their periods around the same time, which was thought to stem from women’s exposure to each other’s pheromones, though this may actually be due to random chance

isolated congenital anosmia (ICA)

a condition in which a person lacks a sense of smell from birth

female copulatory vocalizations

the sounds that women make during sex

2 purposes of making noises during sex

• helpful for letting your partner know what does and doesn’t feel good

• can be used to facilitate your partner’s sexual response

testosterone

a steroid hormone secreted by both the gonads and the adrenal glands

• most is produced in the gonads (testes and ovaries), w a much smaller amt released by the adrenal glands

during critical periods, what contributes to variations in gender identity, sexual orientation, and degree of psychological masculinity and femininity?

unusually high or low T lvls

castration + effects

having the testes removed, which is the primary source of T

loss of libido, more difficult time experiencing erections

hypogonadism

a physical condition in which T production is significantly diminished

testosterone replacement therapy

supplementary T is administered to reverse these effects

oophorectomy + effects

having the ovaries removed (primary source of T)

low libido, difficulties becoming sexually aroused

2 hormones involved in female sexual desire

testosterone, estrogen

__ are related to greater desire for casual sex in men, but only when lvls of the stress hormone cortisol are __

higher T lvls, low

chemical castration

involves administering anti-androgen drugs that block the production of testosterone

estrogen

a steroid hormone produced by the gonads and adrenal glands

effects of estrogen on sexual functioning

• desire

• can help in treating painful sex and arousal difficulties by reversing sexual atrophy (thinning), increasing genital blood flow, and enhancing vaginal lubrication

oxytocin + functions

a neuropeptide hormone manufactured in the brain that has a wide range of effects on human sexual behavior

assist in release of milk during breastfeeding, also plays a vital role in developing bonds btwn romantic and sexual partners bc it’s released during physical intimacy

aphrodisiacs

substances that increase sexual desire and behavior

anaphrodisiacs

substances that reduce sexual arousal and activity

placebo effect

occur when ppl strongly believe that smth they’re taking will have an effect on them, even if the substance or treatment is biologically inert

examples of foods that resemble the penis

banana, cucumbers, carrots, asparagus

examples of foods that represent the vulva

oysters, open figs, peaches

alcohol is an __, but primarily when it’s consumed in small quantities. how? why not in large quantities?

aphrodisiac

reduces inhibitions and creates expectancy effects, where we come to believe that consuming it will put us “in the mood” or make us feel more sexual

in large quantities, it can have a depressing effect on sexual arousal and make it more difficult to reach orgasm by decreasing body and genital sensitivity

chemsex + examples of drugs used

aka “party and play,” turning to drugs to enhance their sexual experience or performance

ecstasy, “poppers,” marijuana, GHB

ecstasy/molly

club drug that seems to enhance sexual desire and produces more intense orgasms in recreational users, but is also linked to reports of erectile difficulties in a large number of men and often delays male and female orgasm

“poppers” + side effects + what happens if swallowed

an inhalant that intensifies the experience of orgasm, usually used by ppl who receive anal sex

headaches, nausea, temporary loss of erection

life-threatening emergency in which delivery of oxygen to tissue and organs is delayed

what is marijuana linked to?

lower reported rates of sexual difficulties

GHB + use in small/microdoses

depressant that reduces brain activity and can potentially render someone unconscious, frequently used among ppl who commit date rape

can be an enhancer for consensual sex, increasing desire, enhancing orgasm, and increasing sensitivity to touch

viagra

an erectile dysfunction medication available by prescription only, primary effect is to create the capacity for an erection and thus makes it easier to become and stay aroused

hypersexuality

“excessive” sexual behavior that causes personal distress

Depo-Provera

an anaphrodisiac that reduces testosterone lvls

SSRIs

an anaphrodisiac that enhances the amt of serotonin

Masters and Johnson Model’s 4 phases to the sexual response cycle

excitement, plateau, orgasm, resolution (EPOR)

excitement phase + length

marks the start of sexual arousal and is characterized by 2 physiological processes that begin here and are carried thru the remaining phases: vasocongestion and myotonia

few moments to few hrs

vasocongestion

an increase in blood flow to bodily tissues (in this case, the genital tissues)

myotonia

the voluntary and involuntary tensing and contracting of muscles both in the genital region and throughout the rest of the body

sex flush

increasingly reddish appearance of chest and torso during arousal

physical changes of excitement phase

vasocongestion, myotonia, inc in heart and breathing rate, sex flush, tightening of scrotal skin, elevation of testes closer to penis, vagina expanding in length, vaginal walls beginning to lubricate

plateau phase + length

sexual tensions continue to mount, an extension of the excitement phase characterized by vasocongestion and myotonia becoming more pronounced

few seconds to a few min

major bodily changes in males, females, and across sexes during plateau phase

complete erection, fully engorged and elevated testes, secretion of pre-ejaculate by the Cowper’s gland

swelling of the nipples and areola, complete expansion and lengthening of the vagina, retraction of the clitoris into the body, development of the orgasmic platform

continued increase in heart and breathing rates, deepening of the sex flush

orgasmic platform

the increased swelling of the outer 3rd of the vagina

prolonging the plateau phase is known as __ and may enhance the pleasure and intensity of a subsequent orgasm

“edging”

orgasm phase + length and what 3 factors it can vary in

the muscles around the genitals make a series of brief, rhythmic contractions

lasts a few seconds, but varies in intensity, number of contractions, and duration

ejaculatory anhedonia

ejaculating without orgasming

can you ejaculate without orgasming and orgasm without ejaculating?

yes

how does ejaculation occur in males?

accumulated secretions of the vas deferens, seminal vesicles, and prostate gland are released into the urethra and expelled from the body

how does ejaculation occur in females?

the orgasmic platform and uterus contract several times, and this may or may not be accompanied by an expulsion of fluid

physical symptoms of orgasm besides ejaculation

inc in heart rate and breathing rate, various forms of myotonia like facial grimaces, contractions of muscles in other parts of the body

nocturnal orgasms/emissions

experiencing orgasms during sleep

“coregasms”

orgasms during exercise

why are painful experiences sometimes experienced as pleasurable?

Pain and pleasure share common neural pathways in the body

2 arguments for the “sperm retention mechanism” about female orgasm

suggests that female orgasm is meant to keep sperm inside

orgasm increases likelihood that a women will fall asleep after sex, and as a result of lying down, sperm loss will be minimized

female orgasm induces a “blow—-suck” mechanism in which the uterine contractions draw sperm further into the reproductive tract

mate-choice hypothesis

argues that the female orgasm is only likely to occur w those men who are the most genetically fit, or who represent the best long-term prospects. in this case, orgasm becomes a reinforcing variable that encourages continued copulation w those partners, thereby promoting reproductive success

alternative theory: women’s climaxes don’t serve any biological purposes and are instead…

a byproduct of the fact that the male orgasm is so heavily favored by our biology. in this case, the female orgasm is nothing but a “fantastic bonus” for women

5 reasons for the “orgasm gap” in sex

• men reach orgasm faster than women on avg during partnered sex among heterosexual adults, and the male orgasm is often viewed as the end of sex

• women’s orgasms vary considerably in terms of bodily location, intensity, and whether there’s an emotional aspect to it

• women are less likely than men to reach orgasm without any genital stimulation at all

• while women are often able to exp multiple orgasms (having 2 or more orgasms during the same sexual event in close succession), this ability has rarely been documented among men

• women are more likely to fake orgasms than are men

“mate retention strategy”

suggests that women fake orgasms to keep their partners from cheating

refractory period + duration and the factors it depends on

a span of time following orgasm during which no additional orgasms are possible, regardless of whether sexual stimulation continues

anywhere from a few min to a few days, depending upon a range of factors, like age and sexual desire

resolution phase + what order does it follow, duration

the return of the genitals to their nonaroused state

can follow any of the previous phases

few min to few hrs, but typically occurs more quickly in older adults than it does in younger persons

postcoital dysphoria

experiencing tearfulness, sadness, or irritability after sex

the triphasic model of sexual response + name them

by Helen Singler Kaplan, a 3-stage model of sexual response that streamlined the Masters and Johnson model while adding a psychological component. reconfigured the model to make it more applicable to the treatment of sexual disorders

sexual desire, excitement, orgasm

what is stage 2: excitement a combination of in the triphasic model?

mashup of the excitement and plateau phases of the Masters and Johnson model

Kaplan’s view on sexual problems

sexual problems could occur at any stage of the model and problems in one stage don’t necessarily translate to problems in other stages

hypoactive sexual desire disorder

distressingly low lvls of sexual desire (tho u can still have a physical sexual response)

responsive desire

desire developing after sexual activity has begun

4 phases of David Reed’s erotic stimulus pathway theory

seduction, sensations, surrender, reflection

phase 1: seduction + what phase it resembles

refers to the set of processes that stimulate sexual activity (spending a lot of time on our appearance, flirting w someone, etc.)

Kaplan’s desire stage

phase 2: sensations + what phase it resembles

sensory input and our sexual fantasies combine to create a heightened sense of arousal that makes us want to continue sexual activity

Masters and Johnson’s excitement and plateau phases

in seduction and sensations phases, psychological factors are seen as propelling…

physiological responses

phase 3: surrender

giving up control to orgasm

phase 4: reflection

when we psychologically reinterpret our sexual exps and give them meaning, may attach a pos or neg meaning to the event which will affect the likelihood of pursuing this partner specifically and sexual activity more generally in the future

issue with the erotic stimulus pathway theory

focuses almost exclusively on the role of psychology and cognitive factors, while giving little attention to physical responses

Basson’s circular model + goal of sexual activity

ppl can enter the cycle at various points, reflecting the fact that desire sometimes precedes arousal, and sometimes arousal comes first

• aka, sexual response isn’t perfectly linear w definitive start and end points

goal is personal satisfaction, which can be physical (orgasm) or emotional (feelings of intimacy and closeness)

range number of contractions in female orgasm

3-15 contractions

3 problems w EPOR model

• suggests linear path is only correct path

• requires orgasm for completion

• focus on physical not psychological

2 stages of the male experience of orgasm

emission, expulsion

emission

semen is deposited into the posterior urethra by contractions of the vas deferens, seminal vesicles, and prostate

expulsion

forced out of the urethra via 10–15 intense, involuntary contractions of the pelvic floor and bulbospongiosus muscles

what causes the feeling of “afterglow” after orgasm?

oxytocin