Pain

Question 1

What is pain?

Answer 1

An unpleasant sensory and emotional experience associated with potential tissue damage.

Question 2

What is acute pain?

Answer 2

Pain lasting less than 12 weeks

Question 3

What is chronic pain?

Answer 3

Pain lasting more than 12 weeks

Question 4

What is nociceptive pain?

Answer 4

Pain that arises from actual damage to non-neuronal tissue.

Question 5

What is neuropathic pain?

Answer 5

Pain that arises from a primary lesion of the nervous system

Question 6

What is the name given to sensory neurones that can sense both external and internal pain?

Answer 6

Nociceptor

Question 7

What is released when tissue is damaged to make nociceptors more sensitive to stimuli?

Answer 7

Bradykinin & Prostaglandin E2

Question 8

Name the two types of afferent nociceptor fibres.

Answer 8

Alpha delta fibre

C-fibre

Question 9

Give the characteristics of alpha delta fibres.

Answer 9

Thinly myelinated
Medium conduction speed
Carry touch, pressure, temperature, FAST pain information

Question 10

Give the characteristics of C-fibres.

Answer 10

Unmyelinated
Slow conduction speed
Carry temperature, touch, pressure, SLOW information

Question 11

Which neurotransmitter do alpha delta fibres release?

Answer 11

Glutamate

Question 12

Which neurotransmitter do C-fibres release?

Answer 12

Glutamate & Substance P

Question 13

Which part of the brain does all sensation (bar Olfactory) pass through?

Answer 13

Thalamus

Question 14

Which part of the brain is responsible for judging the degree of pain?

Answer 14

Insula. Lies within sylvian fissure.

Question 15

Which part of the brain is involved with the emotional response to pain?

Answer 15

Cingulate gyrus. Located on medial aspect of cerebral hemispheres.

Question 16

Where is the periaqueductal grey located?

Answer 16

Midbrain.

Question 17

Briefly describe how the periaqueductal grey descending pain pathway is activated during extreme stress.

Answer 17

Opoid receptors are activated > Reduction in pre-synaptic neuronal sensitivity, reduction in Substance P release > Reduced pain sensation > Analgesia

Question 18

Define analgesia

Answer 18

The selective suppression of pain without effects on consciousness

Question 19

Define anaesthesia

Answer 19

The uniform suppression of pain. Consciousness can be lost.

Question 20

Which drugs bind to opioid receptors?

Answer 20

Morphine, methadone, codeine

Question 21

What is the Melzack-Wall pain gate?

Answer 21

A theory that states that non-painful input closes the ‘gate’ to painful input, preventing pain sensation from travelling to the somatosensory cortex to be perceived.

Question 22

How do local anaesthetics work?

Answer 22

Block sodium channels, preventing neurones from depolarising so no action potential is developed. Results in pain relief as pain is not transmitted.