The Sexual Response Flashcards
The 2 physiologic process responsible for most of the human sexual response in men and women are ______ and ____
Vasocongestion and Myotonia
What are the 4 phases of human sexual response as described by Masters and Johnson?
Excitation, Plateau, Orgasm, and Resolution
Excitation focuses on ______ in both men and women
Vasocongestion
Describe vasocongestion
Increased flow of blood (often w/ decreased blood return)
What does sexual excitation in males entail? (x2)
Penile erection
Scrotal sac thickens, elevates (cremaster muscles)
What does sexual excitation in females entail? (x8)
Vaginal lubrication
Glans clitoris enlarges (similar to penile erection)
Nipples erect (myotonia: muscle contraction)
Breasts enlarge (vasocongestion)
Labia minora swell and open, change in colour (darker)
Upper 2/3rds of vagina balloons
Cervix and uterus stand up: “tenting effect” - creates a more direct line for sperm
Angle of cervical opening more receptive to sperm
What is “sex flush” due to?
vasocongestion in the skin
During what phase of sexual response are HR and RR first affected?
Excitation
What happens to HR, RR, and BP during the plateau phase of sexual excitation?
elevate
The ____ ____ is formed during the plateau phase of sexual excitation in females
orgasmic platform
Describe the orgasmic platform (location, its significance)
outer ⅓ of vagina thickens, swells; w/o it, no orgasm will occur
During the plateau phase in males, the ____ glands secrete fluid through the tip of the penis.
Can this fluid contain sperm?
Bulbourethral (Cowper’s)
Yes!
Does the scrotum hang lower or sit higher during the plateau phase?
Higher
In (males/females), orgasm happens in two stages
Males
What are the two stages of orgasm in males?
Contraction of seminal vesicles, vas deferens and prostate
Contraction of urethra and penis –> ejaculation
In females, orgasm happens all at one time. Describe what is contracting.
Contractions of orgasmic platform
Contractions of uterus
____ is a major player in female orgasm
Oxytocin is a major player in female orgasm
Having several orgasms w/o a refractory period is possible in men or women?
women
During orgasm in both men and women, there is intense ____
Myotonia
As a man ages, does his refractory period shorten or lengthen?
Lengthens
Describe what happens during the resolution stage?
Muscles relax, breathing etc. back to normal, blood returns to central circulation from the genitals
What are some possible health benefits related to orgasm?
General Health (x1-2 orgasms/wk = better immune system)
Pain Relief (menstrual cramps and raise pain tolerance)
Lower CA Rate (Men who have >5 ejaculations/wk while in 20s have a significantly lower rate of prostate CA later in life)
Mood Enhancement (improve mood and ward off depression in women)
Greater Feelings of Intimacy (Oxytocin increases fivefold at orgasm)
Better Sleep (Dopamine, released during orgasm, triggers a stress-reducing, sleep-inducing response that may last up to 2 hrs)
Where is the general emotional response coded for in the brain?
Coded in limbic system
Where is pleasure coded for?
basal forebrain, especially ventral tegmental area and its dopaminergic stimulation of the reward centers of the septal nuclei and the nucleus accumbens
Pleasure centers are _____-mediated and in the more (developed/primitive) part of the (hindbrain/forebrain)
dopamine; primitive; forebrain
How is euphoria achieved in the brain?
Probably by cortex activation
Excitation phase is slower in (men/women)
women
What might the ability to have multiple orgasms be due to in women?
Probably because vasocongestion persists longer in women and clears faster in men
According to some researchers, what are the three types of orgasm that a female can have? What nerves are associated with each?
- From clitoral stimulation, via pudendal nerve
- From G-spot stimulation, via pelvic nerves
- A blend of both
What are other pleasure centers in women, men, and both sexes?
Women (and some men): nipples, remainder of breasts, G-spot
Men: prostate
Both: genital area and others (ears, back of knees, neck, feet, abdomen, thighs, inside of elbows, scalp)
The penile urethra has (one/two/three) separate valves/sphincters. What do they/does it do?
Two
One to let urine into urethra, and another to let semen into urethra
What is going on in retrograde ejaculation? In what population is this occurrence more common? Are there any ill effects from this occurrence?
Urinary valve that opens into bladder is open as the semen heads toward urethra and semen flows into the bladder instead (path of least resistance)
More common in men w/ MS or DM, and in men w/ hx of bladder/ prostate surgery
No ill effects from this occurrence other than infertility if it happens routinely (no sperm arriving to egg)
The female equivalent of the prostate, developed from the same embryonic tissue, are the _______ glands, lining the outside of the __(anatomical location)__, with some ducts found going into the __(same anatomical location)__. If the patient has ducts found going into the __(same anatomical location)__, what can occur?
Skene’s or paraurethral glands; urethra; urethra
Female ejaculation!
When is men’s excitation phase fastest? What happens to men’s sexual excitation phase as they age?
Fastest 16-20 y/o, then slow decline
When a man is middle aged, what will they usually need to get an erection?
Usually will need direct stimulation
When a man is of old age, what will they need a lot of to get an erection?
Need lots of direct stimulation
When is a woman’s excitation phase the fastest? Describe what rate a woman’s excitation phase is in her teens and early 20s.
Slower in teens, early 20s; faster 30’s on
A man’s capacity for maintaining the plateau phase will (increase/decrease) w/ age? What will happen to a woman’s?
Increase (stamina)
Women: Plateau is about the same
The intensity of a (man’s/woman’s) orgasm lessens from mid- to late 20’s, and by middle age, the change is more noticeable.
Men –> ejaculate less volume, less forceful
What is a man’s refractory period like in middle age? In old age?
~24 hours; even longer
Parasympathetic NS is responsible for (Excitation/Orgasm) and Sympathetic NS is responsible for (Excitation/Orgasm) in men.
Parasympathetic (“Point”) = Excitation
Sympathetic (“Shoot”) = Orgasm
Spinal reflexes in erection:
_____ spinal cord responds to stimulation, sends message via _____ to relax penile arteries, and more blood flows to penis.
Sacral
PNS
Ejaculation occurs (lower/higher) in spinal cord because sympathetic trunk is (lower/higher).
Higher; higher
If the spine is severed above the sacrum, will a message got to the brain creating awareness of an erection?
No
Is it possible to control ejaculation? Why or why not?
The ejaculatory message goes to the brain creating awareness, so yes, there is a possibility of control
In women, the neurophysiology of the sexual response is not well understood (because we are magnificent, magical, mysterious creatures of lore). However, we do know that sexual sensations can be transmitted to the brain via the _____ nerve, which is normally used for digestive processes.
Vagus
What is the most studied sex hormone?
Testosterone
Where is testosterone produced in men and women?
testes, ovaries and adrenal glands
Women have __(fraction)__ the amount of testosterone than men, but are ___x more sensitive to it
1/10th ; 10x
Is most testosterone bound or unbound?
bound
_____ is produced by the pituitary and is important for female orgasm
Oxytocin
Are hormones directly responsible for the human sexual response?
No; but they are in animals
What are the two most important factors of the human sexual response?
Psychosocial context and culture
What is dehydroepiandrosterone (DHEA)? Where is it secreted from? Do males have more/less/the same amount of DHEA in their blood?
A weak androgen and a prohormone→ most sex hormones and pheromones are derived from it
Secreted by adrenal glands
Same amount of DHEA is present in male and female blood
What are pheromones? Where do they come from? Where are they sensed? By what?
Pheromones are sexual signalers for both sexes, found in sweat/genital secretions, they are sensed by the vomeronasal organ, located in the nose
What are pheromones? Where do they come from? Where are they sensed? By what?
Pheromones are sexual signalers for both sexes, found in sweat/genital secretions, they are sensed by the vomeronasal organ, located in the nose
T/F Pheromones are also involved in menstrual synchrony
True
Phenylethylamine (PEA) is called the “molecule of ____” and produces what?
love; euphoria
What is PEA?
An amphetamine-like substance produced in brain capillaries and in catecholaminergic terminals
What are low PEA levels associated w/ ?
depression
Is PEA higher earlier/later in a relationship?
Earlier; Some people become addicted to PEA “high” and change partners frequently to get it; some believe real love has “died” as PEA levels decrease in a relationship :(
_______ makes women sexually attractive and receptive (skin, lips, hair, fatty padding (curves), breasts, hips)
Estrogen
____ increases sex drive in both sexes, (though only up to a threshold amount→ more is not always better)
Testosterone
______ are produced in the brain and released in response to touch and sex; produce positive feelings
Endorphins
_____ is a testosterone antagonist and can lower sex drive and has a mild sedative, calming effect
Progesterone
_______ is a neurotransmitter that at low levels intensifies sex drive and at high levels decreases it
Serotonin
SSRIs increase serotonin, thus potentially decreasing sex drive
______ is the neurotransmitter associated w/ all pleasures (increased sex drive, promotes action)
Dopamine
______ decreases sex drive, especially in men
Prolactin
_______ is the hormone produced by the pituitary, antidiuretic (water retention), will increase blood volume and BP. It has been identified as the “monogamy molecule” as it modulates testosterone, levels out extremes of feelings, increases focus in lovemaking
Vasopressin
All of the chemicals/hormones of sexual attraction fluctuate in a ____ hour cycle.
24 hour
Approximately how long does the high of early love last in couples?
6-30 months
