biology of the pain section 3

Question 1

indirect functional imaging techniques

Answer 1

brain activity

measure metabolism of the brain

oxygen content, blood flowing to the region can result in brain activity

Question 2

post mortem

Answer 2

after death

Question 3

fMRI

Answer 3

functional magnetic resonance imaging

Question 4

Pathway from the brain

Answer 4

• suppressive pathway, decreased activity in spinothalamic pathway
• begins periaqueductal gray (brain) —> spinal cord
• 2 neurotransmitters - GABA & enkephalin (opioid)

Question 5

pathway to the brain

Answer 5

noxious stimuli reaches the brain.

• thalamus —> somatosensory cortex (bodily senses) - Spinothalamic pathway
• or anterior cingulate cortex - emotional aspect of pain

Question 6

Spinal reflex pathway and the road example on stabbed toe

Answer 6

• use info about stimuli to initiate reflex
• only require processing at spinal cord lvl
• signals sent to relevant muscles

stabbed toe – info transmitted from nociceptor — to interneuron in spinal cord– motor neuron— action potential—contraction of muscles— reflex arc (responsible for reflex action)

Question 7

Transmittion cell

Answer 7

neuron that transmit info from spinal cord –>brain

Question 8

Interneurons

Answer 8

neuron that stays within CNS- spinal cord

convey signal between 2 neurons

Question 9

2 types of postsynaptic neuron

Answer 9

interneuron

transmission cell

Question 10

stronger stimulus =

Answer 10

more Na+ flow, channels open for longer

Question 11

transduction of extreme temperature

Answer 11

• low or high temp (+45 or -5)
• Thermo-sensitive Na+ channels open
• resulting in receptor potential

Question 12

Prostaglandins

Answer 12

chemicals released from cells,

can make nociceptor more sensitive than normal

Question 13

transduction of chemical signals

Answer 13

• Cell membrane might be broken
• chemicals spill out into surrounding area
• `chemo-sensitive Na+ channels open within membrane of nociceptor nerve endings
• Na+ enters sensory ending to produce receptor potential

Question 14

receptor potential

Answer 14

change in membrane potential

Question 15

transduction of noxious pressure

Answer 15

• pressure applied
• stretch sensitive Na+ channels open
• Na+ more inside the cell
• • change cause membrane potential called receptor potential
• membrane potential close to threshold to produce action potential

Question 16

sensory transduction

Answer 16

detecting sensory stimuli and turning event into a change in membrane potential

Question 17

axon terminal

Answer 17

in spinal cord

Question 18

sensory endings

Answer 18

located in PNS

Question 19

Nociceptors

Answer 19

sensory neuron that detect pain

Question 20

sensory neurons

Answer 20

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

Question 21

nociceptive pain

Answer 21

acute pain; a pain sensation that results abruptly