Block 7

Question 1

What is the problem with pain definitions?

Answer 1

context dependent nature

Question 2

2 categories of operational definitions of pain

Answer 2

noxious and objectionable

Question 3

a stimulus that causes tissue damage

Answer 3

noxious stimuli

Question 4

a stimulus that does not cause tissue damage, but is still painful/unpleasant

Answer 4

objectionable stimuli

Question 5

pleasure circuit that uses a catecholamine

Answer 5

dopamine

Question 6

pleasure circuit that uses a class of peptide transmitters

Answer 6

endogenous opiates

Question 7

a dense fiber tract (collection of axons projecting from hindbrain to forebrain), produces the highest rate of self-stimulation at lower electrical intensities

Answer 7

medial forebrain bundle

Question 8

6 areas that the medial forebrain bundle projects to

Answer 8

cingulate gyrus, septum, amygdala, olfactory and frontal neocortex, parts of basal ganglia, and nucleus accumbens

Question 9

cells of origin for the medial forebrain bundle contain __ as their neurotransmitter

Answer 9

dopamine

Question 10

2 dopamine containing cell bodies

Answer 10

substantia nigra and ventral tegmentum

Question 11

DA projection from the substantia nigra, projects to the striatum

Answer 11

nigrostriatal pathway

Question 12

nigrostriatal pathway shows the relationship between dopamine and __

Answer 12

motor behavior

Question 13

DA projection from the ventral tegmentum to the neocortex

Answer 13

mesocortical pathway

Question 14

DA projection from the VTA to the limbic system/nucleus accumbens

Answer 14

mesolimbic pathway

Question 15

the mesocortical and mesolimbic pathways show the strong link between dopamine and __

Answer 15

reward

Question 16

VTA sends DA projections via MFB to the ___

Answer 16

nucleus accumbens

Question 17

injections of a dopamine __ into the NAc block the rewarding quality of MFB stimulation

Answer 17

antagonist

Question 18

__ is a key site in reward mechanisms

Answer 18

nucleus accumbens

Question 19

injecting a DA __ will make an animal do anything for reward

Answer 19

agonist

Question 20

two drugs that increase dopamine availability in the synapse

Answer 20

cocaine and amphetamine

Question 21

two opposing systems that control pain

Answer 21

ascending nociceptor system, descending analgesia system

Question 22

cause of inflammation

Answer 22

cells release of histamine, bradykinin, prostaglandin, and serotonin

Question 23

nociception is carried to the spinal cord by small unmyelinated fibers (__) and by small myelinated fibers (__

Answer 23

c-fibers, a-delta fibers

Question 24

c and a-delta fibers terminate in edges of the __

Answer 24

dorsal horn

Question 25

peptide located heavily in the dorsal horn of the spinal cord; areas of c-fiber and a-delta fiber termination

Answer 25

substance p

Question 26

pain insensitivity syndrome in humans is caused by a depletion of spinal __

Answer 26

substance p

Question 27

reduce levels of substance p cause severe losses in __

Answer 27

nociception

Question 28

type of second-order nociceptor cells located in the edges of the dorsal horn; receive contacts from both a-delta and c-fibers, and only respond to noxious stimuli

Answer 28

nociceptive specific cells

Question 29

type of second-order nociceptor cells located deeper in the dorsal horn; receive contacts from a-delta receptors and mechanoreceptors (pressure)

Answer 29

wide dynamic range cells

Question 30

electrical stimulation of a number of areas within the __ will render an animal analgesic, or unresponsive to noxious stimuli

Answer 30

brainstem

Question 31

2 brainstem structures involved in analgesia

Answer 31

periaqueductal gray region, and raphe nucleus

Question 32

what mediates analgesia?

Answer 32

endogenous opiate-like molecules

Question 33

located in pituitary and brain, comprised of 31 amino acids

Answer 33

endorphins

Question 34

located in spinal cord and adrenal gland, smaller pentapeptides (5 amino acids)

Answer 34

enkephalins

Question 35

enkephalins co-localize with ___ (nociceptors) in the dorsal horn of the spinal cord

Answer 35

substance p

Question 36

enkephalins produce pain control presynaptically by inhibiting the release of __ by first-order nociceptor cells

Answer 36

substance p

Question 37

pain control is called

Answer 37

analgesia

Question 38

opioids produce spinal analgesia by ___

Answer 38

presynaptic inhibition

Question 39

opioid signal inhibits __ flux into presynaptic terminal, which deactivates __ potential, and inhibits release of __

Answer 39

calcium; presynaptic; substance p

Question 40

__ is contained in presynaptic terminals in the periaqueductal gray region; when it is released onto PAG neurons it causes analgesia

Answer 40

beta-endorphin

Question 41

part of stress-induced analgesia is __ mediated

Answer 41

opioid

Question 42

what causes a runner's high?

Answer 42

release of endorphins and enkephalins

Question 43

what causes the learned helplessness model (animals)?

Answer 43

ACTH (stress hormone), cholecystokinin, and other neuropeptides