sexology ch4

arousal

factors that influence sexual arousal

-brain

-senses

-hormones

-substances

the brain

if the brain does not perceive the stimulus as arousing, the individual will not be aroused

parts of the limbic system

-hypothalamus

-hippocampus

-amygdala

parts of the brain

-hypothalamus

-cerebral cortex

-neurotransmitters

hypothalamus

• Appears to be the most important for normal sexual functioning 

• Destruction or chemical inactivation results in a significant decrease in sexual behavior

cerebral cortex

• Outer layer of the brain which controls our thoughts, memories, imagination, and use of language 

• Sexual function: sexual fantasy 

neurotransmitters

• Presence of dopamine enhances sexual arousal and increases sexual behavior 

• Presence of serotonin reduces sexual arousal and inhibit orgasm 

studies of the limbic system

• The limbic system lights up when aroused 

• Ex. fMRI scanning shows activation of the amygdala 

• Ex. rats pressing a lever that administers a jolt of electricity to their limbic system multiple times an hour 

limbic system

• Set of structures deep within the brain that exerts a profound influence on sexual behavior 

hypothalamus limbic system

• Controls autonomic processes and sexual responses 

hippocampus

Assists in learning and memory

amygdala

• Plays a role in emotional regulation and processing of social information 

the senses

• As input comes in, the brain releases different types of neurotransmitters that can either facilitate or inhibit arousal 

touch

primary erogenous zones and secondary erogenous zones

primary erogenous zones

• Part of the body where nerve endings are present in large quantities 

• Genitals, perineum, nipples, lips and inner thigh 

secondary erogenous zones

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

vision

Cultures and societies have different values for visual preferences of how someone looks like

gender differences for porn

• Previously, we thought that men get turned on more from sexual pictures but recent studies show that women get turned on more 

• Heterosexual men typically have genital arousal when looking at female porn but women can have arousal by looking at lesbians, gay men, or heterosexual couples 

smell

-consciously

-unconsciously (classic conditioning and cultural smells and phermones)

conscious smell

• “She smells good” “he smells bad” 

• This could put someone in the mood or out of the mood 

classical conditioning smell

• You dated a man who always wore Gucci cologne so whenever you smell that cologne, you get turned on 

classical conditioning cultural smells

• Some cultures are more into covering up human scents with deodorants and sprays. Some people may be turned off from natural smells like body odor or smell of sex 

pheromones smell

• Chemicals secreted by the body that play a role in sexual communication 

• More dramatic effect in animals than humans 

Martha McClintock

• Found that females who lived together exhibited menstrual synchrony which was thought to stem from exposure to each others pheromones 

• People who put others sweat on top of their lip for four months had more menstrual synchrony than others who did not 

placebo in men/women study smell

• People were randomly assigned to wear synthetic pheromones or a non pheromone on a daily basis 

• Those who wore pheromones reported having more sex than those who had the placebo

orientation study smell

• Participants rated the pleasantness of armpit smell 

• Gay men did not prefer heterosexual pheromones 

• Heterosexual men and women did not prefer the homosexual pheromones 

ICA study smell

• Isolated congenital anosmia (when people can’t smell since birth) 

• People with ICA report fewer sexual partners as adults 

pill study smell

• Strippers who were ovulating made over $354 per shift while strippers who took birth control made $200 

• The cause for this is unknown. It may be that strippers who are ovulating wore more revealing outfits or that men could smell the pheromones from ovulation

hearing

• Some people like to hear people moan or engage in dirty talk. Some people like to listen to music. Others like silence 

• Men find female sex noises to be very sexually arousing and help facilitate men’s orgasms 

• Women tend to be more vocal and make more sounds during sex 

taste

Some people enjoy the taste of natural bodily secretions (semen, vaginal fluids) while others don’t

hormones

• Testosterone and oxytocin 

• Estrogen does not have a connection to sexual behavior. Estrogen helps maintain the thickness of the vaginal walls and is important for vaginal lubrication 

testosterone

secreted by the gonads and the adrenal glands

. Low testosterone levels can lead to decreased libido, erectile dysfunction, decreased energy, fatigue, and depressive symptoms. Testosterone replacement therapy can help with some of these symptoms, but it doesn't consistently improve mood, cardiovascular risk, or sexual function.

castaration

• Removal of testes which is the primary source of testosterone 

• Men with no testes typically have loss of libido and have a more difficult time achieving erections 

hypogonadism

• A physical condition where testosterone production is diminished 

• Men with lower levels of testosterone have lower levels of sexual desire

testosterone replacement therapy

• People inject testosterone 

• Helps increase sexual desire and activity 

oophorectomy

• Removal of ovaries which is the primary source of testosterone 

• Women without ovaries have low libido and difficulties becoming sexually aroused 

chemical castration

• Administering anti-androgen drugs that block the production of testosterone 

• Popular drug is depo-provera 

• Voluntary in some countries, forced in South Korea 

physical and chemical castration as treatments for sex offenders

• Controversial and very rare 

• People can volunteer for castration as a sex offender 

• Thought it that with the lowered testosterone, offenders are less likely to commit the crime again

oxytocin

• Hormone manufactured in the brain that has a wide range of effects on human sexual behavior 

• Helps generate bonds and attraction 

• Plays at least some role in sexual arousal 

oxytocin studies

• Oxytocin injected in rats have caused erections 

• Administered via nasal spray in humans have found increases in sexual desire and activity 

substances

Some substances have a direct effect on arousal by affecting hormone and neurotransmitter levels

aphrodisiacs

• Increases sexual desire 

• Placebo effect works really well 

anaphrodisiacs

• Reduce sexual arousal and activity 

aphrodisiacs food

• Foods that resemble the penis: banana, cucumber, carrot, asparagus 

• Foods that resemble the vulva: oysters, open figs, and peaches 

aphrodisiacs alcohol

• Reduce inhibitions

• Create expectancy effects 

• A little bit could put people in the mood while a lot could make it hard to orgasm

aphrodisiacs ecstasy

• Users report enhanced desire and more intense orgasms but also erectile difficulties and delays in achieving orgasm 

aphrodisiacs poppers

• Users who inhale poppers report more intense orgasms but some men experience temporary erectile difficulties 

aphrodisiacs marjuana

• About half of users report increased libido and greater sexual pleasure, other half do not

aphrodisiacs viagra

• Creates a capacity for erection in men 

• Linked with the release of oxytocin in male rates, unknown if similar hormonal effects occur in humans 

aphrodisiacs example

• Lowering testosterone levels (Depo-Provera) 

• Ssri’s 

the sexual response cycle

Internal and external bodily processes that occur once sexual arousal begins

the masters and johnson model

• Found a pattern in which majority of people follow 

• Phases 

  • 1. Excitement 

  • 2. Plateau 

  • 3. Orgams 

  • 4. Resolution

excitement two physiological processes

vascongestion and mytonia

vasoconjestion

• Increase in blood flow to bodily tissues 

• Men: penis enlarges 

• Women: clit, labia, and uterus become larger 

myotonia

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

excitement other changes

• Changes of breathing and heart rate

• Get all red (sex flush)

plateau

• Sexual tensions continue to mount 

• Continuation and deepening of the excitement phase 

orgasm

• Muscles around the genitals make a series of brief, rhythmic contraction 

• Similar in both sexes 

• Usually lasts a few seconds 

• Rare for men not to ejacualte but women don’t regularly orgasm 

theories of orgasm men

• Men orgasms has a biological function 

theories of orgasm women

• One theory is that it serves a sperm retention mechanism 

• Another theory is that it promotes reproduction 

• Another theory is that in the first two months in the womb, regardless of gender, the genitals develop from the same tissues

orgasm differences

• Men are more likely to achieve orgasm than women 

• Women have more than one type of orgasm (vaginal insertion, clit play, nipple play, etc) 

• Women can orgasm more in less period of time due to mens refractory period 

• Women tend to fake orgasms more than men

resolution

• Return of the genitals to their non aroused state 

• Length of time varies 

• Behaviors during resolution vary (some people cuddle, some people leave) 

psychological models of sexual response

-triphasic model by Helen Kaplan

-erotic stimulus pathway by David Reed

triphasic model of sexual response

• Three staged model that adds onto Masters and Johnson 

• Sexual problems can occur at any stage of the model and that problems in one stage does not necessarily translate into problems in other stages

first stage of triphasic model

• Sexual desire 

• Desire is the product of many psychological factors such as emotions, stress, prior learning experiences, body image, etc 

second stage of triphasic model

• Combined the excitement and plateau phase of Masters and Johson 

third stage of triphasic model

orgasm

erotic stimulus pathway theory

focuses on the psychological and emotional aspects of sexual response.

four stages of the erotic stimulus pathway theory

1. seduction

2. sensations

3. surrender

4. reflection

seduction erotic stimulus pathway theory

• Refers to the set of processes that stimulate sexual activity 

• Behaviors we employ to attract or seduce people (fixing your physical appearance)

• The way desire is formed between people, which can include wearing makeup, making eye contact, or sexting

sensation erotic stimulus pathway theory

• Five senses and out sexual fantasies combine to create a heightened sense of arousal that makes us want to continue having sex 

surrender erotic stimulus pathway theory

give up or surrender to the orgasm

reflection erotic stimulus pathway theory

• Psychologically reinterpret our sexual experiences and give them meaning