15Physiology of Pain

Hormonal pain inhibitory system Neuronal pain inhibitory system

Substance action Substance action

TASK3. Look at this figure, note morphologic components for this Pain pathway.
Write an explanation of the transmission of pain signals into the hindbrain, thalamus
and cortex via (the fast “pricking pain» pathway and the slow “burring pain» pathway).

TASK8. Look at this figure. Write an explanation about it. Distribution of
curve obtained from a large number of persons shoving the minimal skin
temperature that will cause pain.

43 44 45 46 47
temperature (C°)

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TASK9. Look at this figure “Areas of headache”. Note its morphologic zones and
write an explanation about reasons of headache.

TASK10. Write the explanations for clinical tasks
1.What is the hyperesthesia, analgesia, parestesia?

TASK14. The examination of pain.
This experiment is concerned with the fast component (or first pain) of the pain
sensation. The stimulus for pain is potential or actual damage to the tissues. Note,
however, that in the following experiment very little pressure is needed to elicit this
type of pain.
Draw a 3 cm square on the back of one of the subject's hands, and divide it into a 4
squares. Blindfold the subject, or have him close his eyes. Using a blood lancet, or a
sharp pin, apply brief and light stimuli within the squares. Map out the pain-sensitive
spots within the grids (the areas in between the pain spots will be pain-insensitive). Note
that the subject should report with a "yes" when the stimulus elicits pain and not when
the stimulus can be detected as causing only touch/pressure sensation. Record your
results in the grids drawn in your work book.
Results:

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Quizzes:

1. All of the following are released in response to noxious stimulation at the
damaged site(s) EXCEPT:

A. Globulin
B. Dopamine
C. Arachnoid Acid
D. Acetylcholine
E. Histamine

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2. C fibers transmit which type of pain?
A. Pricking pain
B. Stimulation produced analgesia
C. Referred pain
D. Burning pain
E. Sharp pain

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3. C fibers are
A. small myelinated fibers which carry sharp pain
B. large unmyelinated fibers which carry burning pain
C. small unmyelinated fibers which carry burning pain
D. large myelinated fibers which carry sharp pain
E. large myelinated fibers which carry temperature sensation

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4. Aspirin acts to block the formation of
A. Bradykinins
B. Prostaglandins

 

C. Histamine 54 
D. Dopamine
E. Serotonin

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5. A delta fibers transmit primarily
A. burning diffuse pain information
B. pricking localized pain information
C. aching diffuse pain information
D. visceral pain information
E. phantom pain information

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6. Pain receptors/nociceptors are
A. bipolar cells
B. free nerve endings
C. epithelial receptors
D. Pacinian corpuscles
E. Meissner corpuscles

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7. A. two different pain receptors
B. two different pathways, differing in the number of the synapses
C. two different fibers which conduct the impulses at different velocities
D. two different neurotransmitters
E. two different neuropeptides

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8. A delta fibers transmit which type of pain to VPL?
A. Pricking pain

 

B. Deep pain
C. Visceral pain
D. Burning pain
E. Aching pain

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9. Sharp pain, induced by a skin cut for example, is classified by
A. Burning pain
B. Aching pain
C. Somatic pain
D. Pricking pain
E. Visceral pain

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10. A surgeon attempting to treat chronic pain from the pelvic region will suggest
to make a lesion in the:
A. somatosensory cortex
B. ventroposterior medial thalamus
C. anterior white commissure
D. dorsal column
E. anterior lateral funiculus

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11. In Brown-Sequard syndrome:
A. Tactile and pain sensation are lost contralaterally at different levels below the
lesion.
B. Thermal sensation is lost in the ipsilateral side above the lesion.
C. Kinesthetic and tectile senses are lost ipsilaterally below the lesion.
D. The withdrawal reflex is lost.
E. Atrophy is developed in the muscles below the lesion.

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12. Sharp localized pain is transmitted by:
A. archispinothalamic tract
B. Paleospinothalamic tract
C. Neospinothalamic tract
D. Sympathetic nerves
E. Parasympathetic nerves

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13. Select the best answer: Pain impulses arising within the abdominal and thoracic
cavities may reach the CNS by:
A. somatic nerves innervating
B. sympathetic nerves
C. parasympathetic nerves
D. none of the above
E. all of the above

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14. At the level of the ventral trigeminothalamic tract, pain fibers are generally
crossed or uncrossed?
A. Crossed
B. Uncrossed

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15. Cell bodies of first order pelvic visceral pain fibers are found in:
A. dorsal root ganglion
B. mesentric ganglion
C. superior cervical ganglia
D. inferior cervical ganglion

 

E. middle cervical ganglion

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16. The following pathway is sectioned in a chordotomy for the treatment of pain:
A. Lateral spinothalamic tract
B. Ipsilateral dorsal column
C. Corticospinal tract
D. Spinocerebellar pathway
E. Spino-olivary tract

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17. According to the descending pain suppression theory,
A. Descending spinothalamic fibers produce presynaptic inhibition of Rexed
lamina VII neurons.
B. Pain stimuli activate descending fibers in the dorsolateral fasciculus.
C. Mechanical stimulation produces descending postsynaptic inhibition of Rexed
lamina VIII neurons.
D. Transection of the dorsal column blocks the descending fibers producing
analgesia.
E. Descending corticospinal fibers produce postsynaptic inhibition of nociceptive
spinal neurons will not affect pain sensation.

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18. The Melzack-Wall gate theory refers to:
A. Ascending pain suppression system.
B. Non-noxious input suppresses pain at the spinal cord.
C. Electrical simulation-produced analgesia.
D. Cortical control system suppresses pain.
E. Descending pain suppression system.

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19. Electrical stimulation in the periaqueductal gray elicits:
A. Circular movement
B. Analgesia
C. Catatonia
D. Tremors
E. Hyperactivity

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20. The following nuclei are involved in the serotonergic descending modulation
system of pain:
A. Locus coeruleus
B. Central gray
C. Ventral trigeminal area
D. Raphe nuclei
E. Ventro-posterior medial thalamus

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21. Nociceptors (pain receptors) include what type of nerves?
A. Group I
B. Group II
C. Group III
D. Group IV
E. more than one of the above

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22. The fact that different thermoreceptors have overlapping receptive fields allows
us to respond to a range of temps
A. True
B. False

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23. Thresholds are ____ for touch and temperature and ____ for pain.
A. high; low
B. high; high
C. low; high
D. low; low

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24. When there is damage to cells, the cells will release lots of ___ which will then
stimulat the nociceptors.
A. Na
B. K
C. Cl
D. H

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25.Pain, temperature and touch information synapses in the ______ horn of the
spinal cord in either the _________ or __________
A. ventral horn; substantia gelationsa; nucleus proprius
B. dorsal horn; substantia gelationsa; nucleus proprius
C. ventral horn; gracile fasculus; cuneate fasciculus
D. dorsal horn; substantia gelationsa; nucleus proprius

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26. Central connections (body) for pain and temp is sent through the _________
tract to the ____ of the thalamus.
A. Spinothalamic ; VPM
B. Trigeminothalamic; VPM

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C. Spinothalamic; VPL
D. Trigeminothalamic; VPL

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27. Central connections (for the head) synapse first in the spinal cord
A. True
B. False

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28. The trigeminothalamic tract synapses inthe ___ of the thalamus
A. VPL
B. VPM
C. post central gyrus
D. reticular formation

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29. The trigeminothalamic tract sends info to the:
A. hypothalamus
B. Brodmann area 3,1,2
C. reticular formation
D. all of the above
E. 2 of the above

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30. The homonculus motor cortex is on the ___________ and the homonculus
sensory cortex is on the _____________
A. post central gyrus; pre central gyrus
B. pre central gyrus; post central gyrus

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31. Pain in an area where a limb has been amputated is referred to as... 61 
A. Imaginary pain
B. Sheer pain
C. Invisible pain
D. Phantom pain

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32. What causes us to feel pain?
A. Nerve endings
B. The brain
C. Both of the above
D. Neither of the above

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33. he terms "arthralgia" and "neuralgia" refer to pain located where?
A. Joints and teeth
B. Arteries and nerves
C. Joints and nerves
D. Joints, nerves, arteries, and teeth

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34. The medical community measures pain on a scale of...
A. Zero to 10
B. One to 30
C. Zero to 50
D. One to 100

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35. he pain reliever morphine is derived from which substance?
A. Lead

 

B. Opium
C. Sugar
D. Lithium

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36. If you are in a state of analgesia, you are...
A. Unable to stop pain
B. Unable to feel pain
C. Unable to locate pain
D. Medically in shock because of pain

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36. Some people say they feel pain in their hair.
A. True
B. False

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37. Pain is always a sign that something is wrong.
True
False

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38. Redheads may be more sensitive to pain than people with other hair colors.
A. True
B. False

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39. The most common painful condition is:
A. Headache
B. Low back pain

 

C. Cancer pain 63 
D. Arthritis

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40. Growing pains are real.
A. True
B. False

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41. Weather changes can trigger pain for people with:
A. Asthma
B. Arthritis
C. Migraine headaches
D. All of the above

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42. Women have a higher threshold for pain.
A. True
B. False

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43. The difference between chronic pain and acute pain is:
A. The intensity of the pain
B. How long the pain lasts
C. Where the pain is
D. When the pain comes on

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44. Exercise can help reduce pain over time.
A. True

 

B. False

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45. Icing a sprain:
A. Returns soft tissue to normal
B. Decreases swelling
C. Increases circulation

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46. If you have arthritis, you have:
A. Any of a group of more than 100 medical conditions
B. A condition that only affects seniors
C. A condition that never affects children

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47. Positive thinking about pain:
A. Can reduce pain-related activity in the brain
B. Has no impact
C. Makes pain worse

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48. Mr. John Thomas experiences visceral pain around the upper left lung. All of
the following carry this nociceptive information EXCEPT the:
A. somatic nerves
B. paleospinothalamic tract
C. sympathetic nerves
D. neospinothalamic tract
E. archispinothalamic tract

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49. A toothache can be a symptom of:
A. Eczema
B. Sinusitis
C. Alopecia
D. Hyperthyroidism

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50. Cell bodies of first order pelvic visceral pain fibers are found in:
A. dorsal root ganglion
B. mesentric ganglion
C. superior cervical ganglia
D. inferior cervical ganglion
E. middle cervical ganglion

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51. Stimulation of nociceptors results in the sensation of
A. Touch
B. Light
C. Pain
D. Heat
E. Cold

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52. Where is the right answer? The center of Pain sensation is in the ………
A. anterior nerve root ganglia
B. posterior nerve root ganglia
C. Cerebellum
D. Midbrain
E. post central gyrus of parietal cortex

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53. The doctor diagnosed a referred pain at the left part of arm and shoulder. What
visceral organ can be in hurt?
A. Diaphragm
B. Kidney
C. Heart
D. Testis
E. Gallbladder

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54. Which of the following is true about visceral pain?
A.I t is stimulated by cutting
B. It is stimulated in organs
C. It is easily pinpointed
D. It is stimulated by hot or cold
E. all of the above

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55. The hypersensitivity to pain is......
A. Analgesia
B. Paralgesia
C. Hyperalgesia
D. Hypoalgesia
E. Parastesia

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56. The Pain receptors are:
A. Free nervous endings
B. Pachini bodies
C. Merkel disks

 

D. Rufini bodies
E. Pachini bodies and Merkel Disks

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57. Naked nerve endings are the terminal ends of dendrites of sensory neurons and
are responsible for which of the following sensations?
A .Pain
B. Pressure
C. Limb position
D. None of the above
E. all of the above

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58.Where is a right answer? The first order neurones of Pain sensation from skin
are the cells in the ………
A. anterior nerve root ganglia
B. posterior nerve root ganglia
C. Cerebellum
D. midbrain
E. post central gyrus of parietal cortex

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59. The doctor diagnosed a referred pain at the patient’s epigastric region. What
visceral organ can
be in hurt?
A. Diaphragm
B. Kidney
C. Heart
D. Testis
E. Gallbladder

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60.The abnormal pain sensation is ......
A .analgesia
B. Paralgesia
C. Hyperalgesia
D. Hypoalgesia
E. Parastesia

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61.What this dermatome?
A. This is special zone of the lobe cortex
B. This is segmental field of the skin which innervates by spinal nerve
C. This is special zone of the parietal cortex
D. This is thoracic zone of the skin
E. This is lumbar zone of the skin

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62.This type of pain can occur both in the skin and in almost any deep tissue and
organ…
A. Acute pain
B. Electric pain
C. Throbbing pain
D. Pricking pain
E. Sharp pain

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Correct answers:
1 – B, 2 – D, 3 – C, 4 – B, 5 – B, 6 – B, 7 – C, 8 – A, 9 –B, 10 –E,
11 – C, 12 - C, 13 – A, 14 – A, 15 – A, 16 – A, 17 – D, 18 – B, 19 – B, 20 –D,
21 – B, 22- A, 23 –C, 24 – B, 25 – B, 26 –C, 27 – B, 28 – B, 29 – D, 30 – D,
31 – D, 32 – C, 33 – C, 34 – A, 35 – B, 36 – B, 37 – B, 38 – A, 39 – B, 40 –A,
41 – D, 42 – B,43 –B, 44 – A, 45 – B, 46 – A, 47 – A, 48 – D, 49 – B, 50 – A.
51 – C, 52 – E, 53 – C, 54 – A, 55 – C, 56 – A, 57 – A, 58 –B, 59 – E, 60 – B, 61 – B,
62 – C.

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Recommended literature Basic:
1. A.C. Guyton. Textbook of Medical Physiology: Philadelphia, 2011, 1116p.
2. K.Sembulingam. Essentials of Medical Physiology. Jaypee, 2013, 895p.
3. Sujit K. Chaudhuri. Concise Medical Physiology.- New Central Book Agency,
2013.-752p.
4. Human physiology V.F. Hanong, Lvov: BaK, 2009. – 784p.

Additional literature:
5. Abrahamsen, B., J. Zhao, et al. (2008). "The cell and molecular basis of
mechanical, cold, and inflammatory pain." Science 321(5889): 702-705.
6. Andersson, D. A., C. Gentry, et al. (2011). "TRPA1 mediates spinal
antinociception induced by acetaminophen and the cannabinoid Delta(9)-
tetrahydrocannabiorcol." Nat Commun 2: 551.
7. Berthier, M., S. Starkstein, et al. (1988). "Asymbolia for pain: a sensory-limbic
8. disconnection syndrome." Ann Neurol 24(1): 41-49.
9. Foltz, E. L. and L. E. White, Jr. (1962). "Pain "relief" by frontal cingulumotomy."
J Neurosurg 19: 89-100.
10.Gassner, M., R. Ruscheweyh, et al. (2009). "Direct excitation of spinal
GABAergic interneurons by noradrenaline." Pain 145(1-2): 204-210.
11.Kawasaki, Y., E. Kumamoto, et al. (2003). "Alpha 2 adrenoceptor-mediated
presynaptic inhibition of primary afferent glutamatergic transmission in rat
substantia gelatinosa neurons." Anesthesiology 98(3): 682-689.
12.Li, Y. and J. S. Han (1989). "Cholecystokinin-octapeptide antagonizes morphine

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13.analgesia in periaqueductal gray of the rat." Brain Res 480(1-2): 105-110.
14.Palecek, J. (2004). "The role of dorsal columns pathway in visceral pain." Physiol

Res 53Suppl 1: S125-130.
15.Ploner, M., H. J. Freund, et al. (1999). "Pain affect without pain sensation in a

patient with a postcentral lesion." Pain 81(1-2): 211-214.
16.Rainville, P., B. Carrier, et al. (1999). "Dissociation of sensory and affective

dimensions of pain using hypnotic modulation." Pain 82(2): 159-171.

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