The default sexual brain is what sex?
Female
Where is the sexual CNS center?
Preoptic center of hypothalamus
What are the neonatal influence on sex behavior?
Androgens=male tnedency
A lesion in what CNS region makes no sex behavior regardless of hormones given?
Preoptic hypothalamic center in rats
What is more important in humans than lower species?
Learned behavior is greater than hormonal control
What is a surrogate?
Prostitute
What is auto manipulation?
Masturbation
KEY SLIDE: What are the two main physiological responses in both genders?
Myotonia: increased muscle tension
Vasocongestion: increased blood flow
What are the four stages of sexual response?
Excitement (Arousal)—Focus on sex
Plateau
Orgasm
Resolution
What is the refractory period?
Man cannot achieve orgasm or erection
What is different about female refractory period?
It is shorter: multiple orgasm
What is the secretion in the excitement stage of male arousal? Where from and why?
Cowper’s glands
Neutralizes pH of male urethra
What happens to testes in early phase?
Testes drawn up by cremaster
Protect from getting smushed
Happens before orgasm
What ANS is responsible for erection?
Parasympathetic= POINT
What ANS is responsible for ejeculation?
Sympathetic=SHOOT
What are the nerves allowing for ANS stimulation of erectin?
S2/S4
Outflow of pelvis PNS: increases NOS activity: increased NO: increased cGMP: smooth muscle relaxation: vasodilation: increased blood flow and congestion
How much does blood flow increase in erection?
25-30 fold
What stage of sleep do erection occur?
REM sleep
What is the effect of tactile stimulation of the penis?
Goes back to spinal cord PNS loop activated Some SNS constriction Arterioles dilate Erection
How does viagra work?
inhibit phosphodiesterase to increase cGMP levels
Is there a correlation between length of flaccid penis and erect penis length?
No
Which is more important to erection: vasodilation or venous constriction?
Vasodilation! PNS
Where is the erection center located in spinal cord?
S2-S4
What muscles engorge with blood in erection?
Ischiocavernosus
Bulbospongiosis
What is priapism?
Erection for more than 4 hours.
Who was priapus?
Greek god of fertility who had a large and prominent erection
Orgasm has what two phases?
Emission: semen enters erethra
Ejaculation: contraction of urethral smooth muscle
What contracts in emission?
Rhythmic contraction of: epidydimis vas deferens seminal vesicles prostate
What contraction in ejaculation?
Via pudendal nerves: Bulbocavernosus Ischiocavernosis Perineal Urethra Urethral Sphincters: prevent back flow
What is retrograde ejaculation prevented by?
Urethral sphincters: internal and external
Erection is controlled by what spinal segments? Ejaculation is coordinated in what spinal segments?
Erection: S2=S4
Ejaculation: L1-L2
Erection=
Ejaculation=
Erection=sacral
Ejaculation=lumbar
How fast do rhythmic contractions occur?
0.8 second
Are ANS pathways of ejaculation understood fully?
No… we have an idea but not fully
What is more attractive to a woman, uncircumcised or circumcised flaccid penis?
Circumcised!
What three things happen in sex to the female breast?
Nipple erection
Swelling of breasts
Sex flush
What happens in female excitement phase?
Vaginal lubrication: not from glands
Where is the lubriaction of vagina in female excitement phase from?
Increased blood flow
Transudate across vagina
What increases vaginal lubrication?
ESTROGEN: gels for old ladies
What happens to vaginal size in arousal?
Wider
Deeper
NARROWING entrance
What is not DIRECTLY stimulated for female orgasm?
Clitoris… women would rather drag labia and mons over it than touch it directly
What contracts in female orgasm?
Vagina
Uterus
Rectal sphincter
What does the cervix do in resolution phase of female?
Contractions continue, but are weak and infrequent
Cervix dips into pool of semen at end of vagina
Semen loss is more in what group of women?
Women who have had children
Nulliparous women have less loss
When are all sperm dead?
10 hours after
8 hours 6%
4-6 50%
How long do sperm take to get to fallopian tube?
5 minutes
What is the problem with uterine contractions?
Most activities seem to push semen away from the egg at the top of the oviduct… huh
Uterine
Oviduct
Ciliary
What happens to BP/HR in orgasm?
EVERYTHING GOES UP
Increased HR
Increased Systolic
Increased Diastolic
Increased MAP
What is released hormonally in orgasm?
Oxytocin… people ar trying to make oxytocin sprays to increase couples bonding
What other physiological effects occur in sexual response?
Increaesd:
respiration: may hold breath in orgasm
Sweating: after orgasm
What are the idiosyncrasies of physiology in high sexual excitement?
Decreased bleeding from cuts… more blood to genitals?
Relief from allergies
Increased coordination in spasticity patients
Decreased sensation of PAIN at orgasm
Less gag reflex
What helps calms nerves before public speaking?
Sex… keep in mind when public speaking is in the future
-Dr. Nutting