HLTH377: Week 4: The Sexual Response Cycle

The Dual Control Model

Looks at individual variability in response by looking at sexual response as a gas petal (things that arouse) and brake (things that turn us off).

-> We need more "turn ons" to be happening or in the environment than "turn offs" in order to be aroused or excited.

-> In a poll, our answers for things that are our gas petal or our brake would vary a lot. (individual variability) -> Communication is KEY! There is no way to guess what someone's turn-ons or offs.

• Socio-cultural influences impact what we see as sexy or desireable

Masters and Johnson (1966)

First researchers to study the sexual response cycle physiologically.

Wrote about four, linear stages:

1. Excitement Phase

2. Plateau Phase

3. Orgasm Phase

4. Resolution Phase

Characteristics of the Excitement Phase (1)

"Aroused"

• Blood flow -> vasocongestion (swelling caused by inc blood flow makes genitals more sensitive -> penile and clitoral erection -> erection of nipples

• Inc heartbeat, BP rises, inc breathing rate, flushed skin

• Bulbourethral & Bartholin's glands: produce more lubrication NOTE: Wetness is not a perfect indicator of arousal -> People with higher natural levels of estrogen, such as young people, tend to lubricate more easily and in greater amounts compared to people who have lower levels of estrogen, are on birth control, are breastfeeding, or are in menopause

Characteristics of the Plateau Phase (2)

"On edge"

• Arousal, inc heart beat

• Blow flow inc

• Adrenaline kicks in to ensure we have stamina

• Less anxiety/stress

• Often a reduced sensitivity to pain/ pain turns to pleasure

• Vaginal opening/canal loosens/elongates like an accordion

• Muscle spams

• Muscles at base of penis contract -> testes enlarge; are pulled in towards body

Characteristics of the Orgasm Phase (3)

"The big 'O'"

• Involuntary contractions -> For PENIS: pelvis, prostate gland, vas deferens, and seminal vesicles; usually involves ejaculation -> For VULVA: pelvis, vagina,uterus; cervis dilates for 20-30 min; uterus contracts to "suck-in" sperm

• Flood of dopamine (feels good!)

• Oxytocin enhances pubococcyygeus (PC) muscle contractions

• Lateral orbitofrontal cortex turns off (inhibits self-evaluation; less fear, anxiety, emotions, and aggression)

Refractory Period

Period of reduced or absent sexual arousability after orgasm where another orgasm likely cannot be achieved.
- May come w/ inc prolactin -> supresses excitement

In MEN: lasts minutes, to hours, up to one day.
WOMEN do not have a refractory period.

Multiple Orgasms

A series of climaxes that come close together (a few minutes) but are separate with an interruption or pause between them.

Serial Orgasms

Orgasms that occur one right after the other, with seconds in between, and no lapse or rerun of the arousal cycle.

Characteristics of the Resolution Phase (4)

Physiological arousal subsides -> Can happen w/ or w/o orgasm

If orgasm is reached:

• Refractory period (more common in men)

• Flood of oxytocin ("Let's bond! I feel so close to you rn."

• Muscular and psychological relaxation

• Blood flow returns to resting state -> may come w/ lightheadedness

Sexual Desire Phase - Kaplan (1979)

"What triggers arousal?"

• Desire for sexual activity - libido, sexual appetite, sexual passion, sexual urge- can be aroused by physical, intellectual, emotional, or hormonal stimuli

• We can have desire without engaging in sexual behavior w/ ourselves or others

• We don't get "turned on" by the same things; arousal is very subjective

• Can be like an appetite -> "I'm so hungry!" vs. "I wasn't hungry but that looks good" or "Sure, I'll eat it."

• If no sexual desire, can lead to difficulties reaching other stages

-Levin (2002) added (1) spontaneous or (2) induced by physical excitation

Sexual Function and Problems with Adolescents and Young Adults (O'Sullivan, 2015)

Qualitative studies reveal that young people often experience low desire, engage in sex for another’s pleasure rather than their own, have trouble reaching orgasm, and worry about their “performance”.

Possible Treatment for Sexual Dysfunction

Scaling back sexual behavior (perhaps all the way to abstinence) -> Working on individual issues re: sexual behaviors (ex. working on anxiety, depression, sexual therapy, couples' therapy, etc). -> Slowly scaling sexual behavior to meet emotional/psychological state where it is -> Increasing sexual behavior back up gradually