Week 9: Pain

Question 1

What is pain?

Answer 1

Pain is defined as a sensation perceived that is triggered by noxious stimuli.

Question 2

How is pain characterized?

Answer 2

Pain is a subjective sensation that involves multiple brain regions and depends on the decision-making processes of the brain.

Question 3

Is the pain experience consistent?

Answer 3

No, the pain experience is highly variable and individual.

Question 4

Can pain response vary for the same injury?

Answer 4

Yes, variability in response can occur even in one individual for separate episodes of the same type of injury.

Question 5

Can pain be quantified?

Answer 5

Pain cannot be quantified.

Question 6

What influences pain perception?

Answer 6

Pain perception is influenced by circumstances and emotional context.

Question 7

What are nociception signals?

Answer 7

Neuronal signals that alert the brain to an injury are called nociception and are readily quantifiable.

Question 8

Characteristics of Fast Pain

Answer 8

Sharp, localized, rapid perception

Question 9

Characteristics of Slow Pain

Answer 9

Diffuse, dull pain, hard to localize, delayed perception, can increase over time

Question 10

Characteristics of Acute Pain

Answer 10

Pain lasting less than 6 months

Question 11

Characteristics of Chronic Pain

Answer 11

Pain lasting more than 6 months

Question 12

Characteristics of Productive Pain

Answer 12

Correlated to tissue damage; purpose to warn injury lessens as damage resolves; accompanied by sympathetic nervous system response

Question 13

Characteristics of Non-productive Pain

Answer 13

Doesn’t serve as a warning; cause of pain may be difficult to identify; often accompanied by stress and depression

Question 14

Definition of Somatic Pain

Answer 14

Pain from somatic structures

Question 15

Definition of Visceral Pain

Answer 15

Pain from organs and involuntary body structures

Question 16

Definition of Neuropathic Pain

Answer 16

Pain associated with damage to or disease of nervous system

Question 17

What are the two main types of nociceptive neurons?

Answer 17

Aẟ Fiber and C Fiber.

Question 18

What is the function of Aẟ Fibers?

Answer 18

Myelinated fibers that transmit sharp, well-localized pain.

Question 19

What is the function of C Fibers?

Answer 19

Unmyelinated fibers that transmit dull, aching pain that is difficult to pinpoint.

Question 20

What triggers nociceptors?

Answer 20

Nociceptors respond to temperature (hot or cold), mechanical (tearing, slicing, ripping), and chemical (acid, base) information.

Question 21

What does it mean that nociceptors are high-threshold cells?

Answer 21

Only actual tissue damage can elicit a signal of sufficient intensity to activate these neurons.

Question 22

How do pain fibres travel from the periphery?

Answer 22

Pain fibres travel from the periphery to the dorsal horn of the spinal cord.

Question 23

What tracts do pain fibres ascend through to reach the brain stem?

Answer 23

They ascend via afferent fibres through the spinothalamic and spinoreticular tracts to the brain stem.

Question 24

What are two important neurotransmitters associated with nociception?

Answer 24

Substance P and glutamate are two important neurotransmitters associated with nociception.

Question 25

What can modulate pain signals?

Answer 25

Descending inhibitory pathways can modulate pain signals.

Question 26

What can influence pain signals?

Answer 26

Endogenous opioid peptides can also influence pain signals.

Question 27

What is productive pain?

Answer 27

Immediate pain associated with injury, correlating with tissue damage.

Question 28

What is non-productive pain?

Answer 28

Ongoing pain experience after injury and healing begins, caused by changes around neurons.

Question 29

What is allodynia?

Answer 29

A non-painful stimulus producing a sharp pain response, indicating an error in neuronal conduction. ## Footnote Example: Light feather touch causing pain.

Question 30

What is hyperalgesia?

Answer 30

Exaggerated response from a normally painful stimulus, indicating increased sensitivity to pain.

Question 31

What is primary hyperalgesia?

Answer 31

Pain sensitivity occurring directly in the damaged tissues.

Question 32

What is secondary hyperalgesia?

Answer 32

Pain sensitivity occurring in surrounding undamaged tissues.

Question 33

What is the Gate-Control Theory of Pain?

Answer 33

The theory proposes that non-painful input closes the 'gates' to painful input, preventing pain sensation from travelling to the CNS.

Question 34

How can incoming nociceptive signals be blocked?

Answer 34

Incoming nociceptive signals on Aδ and C fibers can be blocked by signals on Aβ fibers.

Question 35

What are Aβ fibers?

Answer 35

Aβ fibers are highly sensitive nerve fibers associated with mechanoreceptor responses.

Question 36

What is the function of low-threshold neurons?

Answer 36

Low-threshold neurons allow fine discrimination.

Question 37

What is the Wong-Baker face scale used for?

Answer 37

The Wong-Baker face scale is used for pain assessment.

Question 38

What is the scale range of the Wong-Baker face scale?

Answer 38

The scale ranges from 0 to 5.

Question 39

What does a score of 0 on the Wong-Baker face scale indicate?

Answer 39

A score of 0 indicates 'No hurt'.

Question 40

What does a score of 1 on the Wong-Baker face scale indicate?

Answer 40

A score of 1 indicates 'Hurts a little bit'.

Question 41

What does a score of 2 on the Wong-Baker face scale indicate?

Answer 41

A score of 2 indicates 'Hurts a lot more'.

Question 42

What does a score of 3 on the Wong-Baker face scale indicate?

Answer 42

A score of 3 indicates 'Hurts even more'.

Question 43

What does a score of 4 on the Wong-Baker face scale indicate?

Answer 43

A score of 4 indicates 'Hurts a lot'.

Question 44

What does a score of 5 on the Wong-Baker face scale indicate?

Answer 44

A score of 5 indicates 'Hurts worst'.

Question 45

What is neuropathic pain?

Answer 45

Neuropathic pain is defined as pain initiated or caused by a primary lesion or dysfunction in the nervous system.

Question 46

What characterizes neuropathic pain?

Answer 46

It is a complex, chronic pain state that is usually accompanied by tissue injury.

Question 47

What happens to nerve fibers in neuropathic pain?

Answer 47

Nerve fibers can be damaged, dysfunctional, or injured.

Question 48

What do damaged nerve fibers do?

Answer 48

Damaged nerve fibers send incorrect signals to pain centers.

Question 49

What are some causes of neuropathic pain?

Answer 49

Several conditions can cause neuropathic pain, including alcoholism, amputation, back, leg, and hip problems, chemotherapy, diabetes, facial nerve problems, AIDS, multiple sclerosis, shingles, and spine surgery.

Question 50

What are the symptoms of neuropathic pain?

Answer 50

Symptoms include shooting and burning pain, tingling, and numbness.

Question 51

What is Phantom Limb Pain?

Answer 51

Pain attributed to a missing limb, usually felt in the most distal structures (e.g. fingers, toes). ## Footnote It is generally described as shooting, stabbing, pricking, boring, squeezing, throbbing, and/or burning pain.

Question 52

When is Phantom Limb Pain more likely to occur?

Answer 52

It is more likely to occur if there was pain in the tissues before amputation.

Question 53

What causes Phantom Limb Pain?

Answer 53

One theory suggests that nerve endings at the site of the amputation continue to send pain signals to the brain, making the brain think the limb is still there. ## Footnote The brain's memory of pain is retained and interpreted as pain, regardless of signals from injured nerves.