More Than Nociception pt2

Question 1

How is nociceptive input divided? What fibers carry out these divisions?

Answer 1

VISCERAL

• From internal organs of the
  body, e.g.:
• Liver
• Gut
• Stomach
• Bladder
• Blood vessels
  Carried largely by C fibers

NON-VISCERAL

• From body parts that are not
  internal organs
• Bones
• Ligaments
• Skeletal muscles
• Skin
  Carried largely by A-delta fibers

Question 2

Name and describe the two types of fibers:

Answer 2

A-Delta fibers:

• myelinated
• mechanical, thermal pain
• very fast

C Fibers:

• Non-Myelinated
• mechanical, thermal, chemical pain
• Slower

Question 3

What is placebo analgesia and name its related body parts

Answer 3

positive expectations reduce pain

Positive Expectations:
The dorsolateral prefrontal cortex
(DLPFC)

Increase in endogenous opioids in the anterior cingulate cortex

Periaqueductal gray controls the release of endogenous opioids

Question 4

What are some sources of nocebo effects in pregnant women?

Answer 4

• Interactions with family members and friends
• other people’s fears
• other people’s beliefs
• Interactions with health care providers
• attending prenatal check ups
• being given information about risk

Question 5

What is nocebo hyperalgesia? what does this lead to? describe all related brain areas/chemicals

Answer 5

When negative expectations increase pain

Expecting pain creates a state of anticipatory anxiety, which:
* increases muscle tension and any related pain
* increases stress and weakens the body’s own ability to cope with pain
* suppresses endogenous opioids

Expectations are in the dorsolateral prefrontal cortex

Anxiety:
Cholecystokinin (CCK)…
is an anxiety-promoting hormone, which also has a facilitating effect on pain transmission

Stress:
The hypothalamic-pituitary-adrenal axis (HPA)
release cortisol, suppress immune system

Suppress endogenous opioids:
Nucleus Accumbens (NAcc)