Neurophys of Sexual Response

Question 1

Vaginal photoplethoysmograph

Answer 1

Gets inserted into the vagina

Gives information about blood volume, vaginal pulse and heart rate

Question 2

PDE5 inhibitors for ED

Answer 2

PDE5 is the enzyme that breaks down NO (so more NO = more erection)
Inhibitors only work if some NO is being produced from mental sexual arousal

Question 3

2 techniques you can use to bypass mental arousal requirements in men

Answer 3

Injecting PGE1 (direct vasodilator)
Vacuum devices (traps blood in the penis)

Question 4

What are the results on sexual function going to be from a radical prostatectomy?

Answer 4

Erectile function could be affected
Genital sensation will not be affected (pudendal nerve is fine)
Still able to reach orgasm
Will not have an ejaculate

Question 5

5 nerves in the male

Answer 5

S2-4 autonomic
Pudendal nerve (sympathetic, S2-4 autonomes, S2-4 somatics)
Pelvic nerve (autonomic)
Cavernous nerve (autonomic)
Dorsal nerve (from pudendal)

Question 6

Does subjective sexual excitement correlate with genital swelling in females?

Answer 6

Nope

Question 7

What types of nerves transmit the signals that allow for vasocongestion of sinusoidal tissue?

Answer 7

Autonomic nerves

Question 8

Genital stimulation reflexively triggers erection from what spinal levels?

Answer 8

Autonomic nerves at S2-4

Question 9

Psychogenic center works through what nerve

Answer 9

Hypogastric nerve transmits mental sexual excitement to trigger the erection

Question 10

What centers are preserved in

1. Sacral SIs
2. Cervical SIs

Answer 10

1. Reflexive erections are impaired, but still possible through the psychogenic center
2. Psychogenic center is impaired, but reflexive erections are still possible

Question 11

Ejaculation definition

Answer 11

The process of sperm transport from the testes to the urethral meatus
Independent from erections

Question 12

Orgasm definition

Answer 12

Brain event of altered consciousness
Intense pleasure followed by well being, rhythmic pelvic muscle contractions
Usually (but not always) accompanies ejaculation

Question 13

2 phases of ejaculation

Answer 13

Seminal emission

Propulsatile ejaculation

Question 14

Seminal emission (nerves involved, voluntary or not)

Answer 14

Sympathetic T10-L1

Some voluntary control (can start and stop this process)

Question 15

Propulsatile ejaculation (nerves involved, voluntary or not)

Answer 15

Expulsion
Sacral autonomics and somatic/pudendal
Not under voluntary control

Question 16

“Point of no return” in ejaculation

Answer 16

Switch from seminal emission to propulsatile ejaculation
Seminal fluid increases
Closure of bladder neck and external sphincter
Increased intraprostatic pressure

Question 17

What happens with sphincters and muscles during ejaculation

Answer 17

Bladder external sphincter opens

Muscles contract

Question 18

What are vibrators in men used for

Answer 18

For a complete lesion above T10
Possible to trigger the ejaculation reflex through intense penile stimulation
Need intact lumbosacral cord
Reflex erections and intact bulbocavernosus reflex are promising signs

Question 19

Electroejaculation

Answer 19

When SCI is below T10 (lumbosacral cord is damaged)
Rectal probe is used to “jump start” the efferent pathways of seminal emission
May require general anesthesia if you’re an incomplete SCI

Question 20

What is the refractory period?

Answer 20

How long it takes for the NTs to be repackaged after orgasm

Question 21

Orgasm after SCI

Answer 21

Orgasm can be genitally or non-genitally triggered from sexually sensate areas or fantasy
40-60% able to achieve an altered orgasm (more likely if an incomplete SCI)
Vibrators can help in both sexes
Women with complete lesions without genital sensation can orgasm from vibrostimulation to the cervix

Question 22

4 tests to predict sexual potential

Answer 22

Bulbocavernosus reflex
Pinprick sensation
Voluntary anal contraction
Anal tone

Question 23

Bulbocavernosus reflex

Answer 23

Squeeze of glans/clitoris will see a contraction of the anal sphincter
Shows you are reflexive of intact sensory and motor sacral pathways
Predictive for reflex erection/vaginal/clitoral arousal
Positive is confirmatory, but negative is not (some normal people have negative response)

Question 24

Genital orgasm requires a positive result from what 2 tests?

Answer 24

Positive genital pinprick (or cold) - intact upgoing lateral spinothalamic
Voluntary anal contraction - intact down going corticospinal tract

Question 25

Anal tone test

Answer 25

Snug to inserted finger
Only helpful test for autonomic testing
Positive: lumbosacral autonomics and motor tracts are likely unimpeded
Negative: may explain disordered ejaculation