Nociception

Question 1

Nociceptors exist as free nerve endings activated only when the stimulus is ___.

Answer 1

strong enough to cause damage.

Question 2

___ nociceptors have fast responses

Answer 2

thermal/mechanical

Question 3

___ nociceptors are myelinated

Answer 3

thermal/mechanical

Question 4

___ nociceptors are unmeylinated

Answer 4

polymodal

Question 5

thermal/mechanical noiceptors are assocaited with ___ pain

Answer 5

sharp, prickling pain

Question 6

polymodal nociceptors are assocaited with

Answer 6

with high intensity mechanical, chemical, hot, and cold stimuli.

Question 7

Nociceptive specific neurons are found in___of the spinal cord

Answer 7

Lamina 1

Question 8

nocipceptive specific neurons have ___ receptor fields

Answer 8

small

Question 9

nocieptive specific neurons carry

Answer 9

only info about noceipcetion

Question 10

. Wide dynamic range neurons (WDR) are found in ___ of the spinal cord

Answer 10

Lamina 5

Question 11

Wide dynamic range neurons carry information

Answer 11

from both mechanoreceptors and noiceptors

Question 12

Wide dynamic range neurons have ___ receptor fields

Answer 12

larger

Question 13

. hyperalgesia is what happens when you have increased sensitivity to the ____.

Answer 13

surrounding unharmed region of a damaged area

Question 14

with hyperalgesia Subsequent stimuli result in the

Answer 14

enhanced sensation of pain

Question 15

referred pain is the result of a ____

Answer 15

lack of nociceptive output neurons in the dorsal horn that are dedicated to visceral pain

Question 16

dissociated sensory loss is when you have reduced sensation of epicritic sensation in the opposite side of the body from where you have ___.

Answer 16

reduced sensation of temperature and pain

Question 17

Pain modulation can occur as the result of the descending pathway synapsing with

Answer 17

an opiate containing interneuron

Question 18

The opiate containing interneruon synapses with the ascending pathway in the dorsal horn releasing enkephalin that dampens

Answer 18

both presynaptic and postsynaptic neurons

Question 19

pain vs. noiception?

Answer 19

pain is a psychological perception

Question 20

where are the cell bodies of noiceptors?

Answer 20

located in the dorsal root and trigeminal ganglia.

Question 21

Nociceptors exist as free nerve endings that do not have ___

Answer 21

peripheral structures

Question 22

____ nociceptors have small-diameter, thinly myelinated A

Answer 22

thermal/mechanical

Question 23

___ noiceptors have small- diameter, unmyelinated C fibers

Answer 23

polymodal

Question 24

If the stimulus intensity is raised to a level that activates A

Answer 24

tingling sensation

Question 25

If the stimulus intensity is raised to a level that activates A

Answer 25

sharp pain

Question 26

If the stimulus **intensity is increased further,** so that the small-diameter**, slowly conducting C fiber axons** then a a ___ is experienced.

Answer 26

duller, longer-lasting sensation of pain

Question 27

The vanilloid receptor TrpV1 is found in both\_\_\_ fibers

Answer 27

C and A

Question 28

TRPv1 is Activated by stimuli such as (3)

Answer 28

capsaicin, heat, acids and anandamide

Question 29

\_\_\_ receptors may respond to endogenous chemicals similar to capsaicin that are released with peripheral injury

Answer 29

TrpV1

Question 30

in the flare region following hyperalgesia, ___ drops dramatically

Answer 30

threshold sensitivity

Question 31

The release of ___ \_\_\_ and ___ , and other agents from the site of injury **enhances the responsiveness** of **nociceptive endings**

Answer 31

bradykinin, histamine, prostaglandins \*these make protect yoiu from contuoally hurting yourself

Question 32

Electrical activity in the nociceptors also stimulates the local release of chemical substances (such as substance P) that cause \_\_, \_\_\_, and \_\_\_

Answer 32

vasodilation, swelling, and the release of histamine from mast cells.

Question 33

aspirin and other NSAIDS act by inhibiting cyclooxygenase, an enzyme important in the biosynthesis of \_\_\_

Answer 33

prostaglandins

Question 34

Local pain can be sensed even when nociceptive pathways are damaged bc pain can arise spontaneously in the

Answer 34

absence of activity in nociceptors.

Question 35

branches of A and C noceiptive fibers descend for a few segments as part of the ___ when they enter the spinal cord

Answer 35

dorsolateral tract

Question 36

Nociceptive fibers terminate primarily in the \_\_\_

Answer 36

superficial dorsal horn (lamina 1 and 2)

Question 37

Few if any neurons in the dorsal horn are specific to conveying ___ pain

Answer 37

visceral

Question 38

Referred pain is the displacement of pain from a visceral structure such as to a somatic area of the body because of the convergence of visceral and cutaneous nociceptors onto the same ____ projection neurons

Answer 38

dorsal horn

Question 39

ureteral pain (like in passing a kidney stone) referred to ___ and \_\_\_

Answer 39

lower abdomen and back

Question 40

bladder pain referred to the \_\_\_

Answer 40

perineum

Question 41

Prostate pain with a characteristic distribution

Answer 41

above and below the effected side

Question 42

Axons from the from ganglia associated with nerves ___ carry information from facial nociceptors and thermoreceptors

Answer 42

5, 7, 9, 10

Question 43

The major target nuclei of the ascending pain and temperature axons are the ___ of the thalamus

Answer 43

vpl and vpm

Question 44

Somatosensory cortex receives nociceptive information from ____ of the thalamus.

Answer 44

VPN

Question 45

how are nocipceptive inpurs organized in the cortex?

Answer 45

No orderly arrangement

Question 46

Neurons in the ___ make inhibitory connections in laminae I, II, and V of the dorsal horn (these laminae are also the site of termination of nociceptive afferent neurons)

Answer 46

rostroventral medulla

Question 47

Electrical stimulation of\_\_\_ or \_\_\_results in the inhibition of dorsal horn neurons that respond to noxious stimulation.

Answer 47

periaquedcutal gray or rostroventral medulla

Question 48

Electrical stimulation in either the PAG or rostroventral medulla results in the inhibition of dorsal horn neurons that respond to noxious stimulation. this effect cna be eliminated with X of the

Answer 48

dorsolateral funiculus (which is carrying this descending information)

Question 49

Administration of low doses of opiates directly into \_\_ and ___ produce analgesia

Answer 49

PAG and rostroventral medulla

Question 50

The descending inhibition of spinothalamic tract neurons appears to be mediated by the activation of ____ interneurons in the dorsal horn.

Answer 50

enkephalin

Question 51

The descending axons of serotonergic and noradrenergic neurons from the nucleus raphe contact (2)

Answer 51

1. dendrites of ALS neurons 2. inhbiitory neurons in superficial dorsal horn

Question 52

The ___ contains a high density of enkephalin- and dynorphin-containing interneurons

Answer 52

superficial dorsal horn

Question 53

opiates and opioid peptides regulate nociceptive transmission by releasing

Answer 53

glutamate, substance P, and other transmitters

Question 54

Neurons in the periaqueductal gray matter make excitatory connections in the\_\_\_

Answer 54

rostroventral medulla

Question 55

Opiate receptors are located both on the

Answer 55

terminals of nociceptive afferents and on the dendrites of postsynaptic neurons.

Question 56

Opiates also act postsynaptically at afferent synapses to suppress the activity of \_\_\_

Answer 56

nociceptive dorsal horn neurons.