Neuro Quiz 1 Burrell Receptors And Reflexes Ssom

Front 1

Location of somatic sensory cell's soma

Back 1

DRG

Front 2

Large fibers (I-II) are in the _ division of dorsal root;
they carry _ info

Back 2

medial division
PVT

Front 3

Smaller fibers (III-IV) are in the _ division of the dorsal root and carry _ info

Back 3

lateral division
PT

Front 4

How are fibers categorized

Back 4

By size and whether has myelin

Front 5

Myelinated - Large

Back 5

Ia, Ib (Aalpha)

Front 6

Myelinated - Small

Back 6

II (Abeta)

Front 7

Myelinated - Smallest

Back 7

III (A delta)

Front 8

Unmyelinated

Back 8

IV (C)

Front 9

Sensory Modality

Back 9

refers to environmental info a receptor responds to (visual, mechanical, olfactory, etc.)

Front 10

Labeled line

Back 10

receptor only responds to specific kind of stimulus
primary method of encoding sensory stimuli

Front 11

Frequency Coding

Back 11

pattern of activity communicates additional info about the stimulus
used to detect between stimuli of the same sensory modality
(same thermal receptor but more active at higher temp)

Front 12

Receptor potential
(aka)

Back 12

generator potential

Front 13

Receptor potential
(def)

Back 13

graded depol of the sensory ending due to reception of the appropriate stimuli
(for mechanosensory cells, caused by mech deformation causing opening of stretch activated ion channels)

Front 14

Accessory Structures
(where located, 2 roles)

Back 14

specializations at the endings of mechanosensory cells that help determine:
(1) what kind of stimulus (temp, pain, vibration) a sensory cell responds to
(2) how a sensory cell responds to a given stimulus (ex: adaptation)

Front 15

Adaptation

Back 15

the response of a neuron diminishes even though stimulus still applied
depends on the physical properties of the accessory structure and/or properties of the ion channels in a given sensory neuron

Front 16

Pacinian corpuscle
(as example of adaptation)

Back 16

water-filled balloon example

Front 17

Mechanosensory receptors
2 general types

Back 17

slow- and fast-adapting types

Front 18

Slow-adapting sensory cells

Back 18

exhibit decrease in response after stimulus onset, but maintain a relatively constant level of activity after initial response (never stop firing AP)

Front 19

Rapidly-adapting sensory cells

Back 19

respond to stimulus onset and cease to respond even if stimulus is still being applied.
frequently exhibit additional response when the stimulus ends (offset response)

Front 20

5 Receptor Types
(name)

Back 20

Meissner corpuscles
Merkel disks
Pacinian corpuscles
Ruffini corpuscles
Nociception

Front 21

Meissner corpuscles
(location, type of adaptation, detect what, role)

Back 21

superficial
rapidly-adapting mechanoreceptors
detect low-freq vibrations (flutter)
provide feedback during initial stage grasping

Front 22

Merkel disks
(location, type of adaptation, respond to)

Back 22

superficial
slow-adapting mechanoreceptors
respond to sustained pressure

Front 23

Pacinian corpuscle
(location, type of adaptation, have _ receptive fields, sensitive to _)

Back 23

deep tissue
rapidly-adapting mechanoreceptors
very broad receptive fields
sensitive to vibration

Front 24

Ruffini corpuscles
(location, type of adaptation, have _ receptive fields, respond to )

Back 24

deep tissue
slow adapting mechanoreceptor
large receptive fields
respond to skin stretch, usually in preferred direction

Front 25

Free nerve endings
(respond to)

Back 25

pain

Front 26

Do nociceptors have accessory structures?

Back 26

NO

Front 27

2 basic types of nociceptors

Back 27

Mechanical nociceptors
Polymodal nociceptors

Front 28

Mechanical nociceptors
(respond to, signals conducted by)

Back 28

responds only to mechanical damage
type III (Adelta) axons

Front 29

Polymodal nociceptors
(respond to, signals conducted by)

Back 29

respond to mechanical and thermal (40 -60 C)
Type IV (C) fibers
(the other thermal receptors in body saturate at 40C)

Front 30

Important signaling molecules in nociception

Back 30

K+
H+
ATP
Bradykinin
Prostaglandin
Serotonin
Substance P

Front 31

Nociceptive heat detected by ...

Back 31

activation of thermal-sensitive Ca2+ channel, called the vanilloid receptor 1 (VR1) which also open in response to many ligands including H+ and capsaicin

Front 32

erythromelalgia

Back 32

inherited neural disorder in which people feel extreme burning sensation in response to a non-nociceptive warming
increased activity in Na 1.7

Front 33

2 components of painful stimuli

Back 33

First Pain
Second Pain

Front 34

First Pain
(conducted by, composed of, localization, tolerance)

Back 34

Type III (Adelta)
sharp, prickling component to pain
well localized an tolerated

Front 35

Second Pain
(conducted by, speed, localization, tolerance)

Back 35

Type IV (C) fibers
noticeable delay (1 sec) relative to first pain
poorly localized (diffuse) and not as well tolerated as first pain

Front 36

Referred Pain
(what, cause)

Back 36

pain that occurs internally but felt on body surface
due to convergence of nociceptive inputs from both internal regions and cutaneous skin regions onto the same projection neurons in dorsal horn

Front 37

Modulation of Painful stimuli - "Gate-control theory"

Back 37

painful stimuli altered by activation of non-nociceptive mechanosensory neurons that carry sensory input to dorsal horn (Aalpha/Abeta axons)
both go to projection neuron and inhib interneuron, but C fiber disinhibition on inhib interneuron

Front 38

Hyperalgesia
(def, 2 forms)

Back 38

the sensitization of nociceptors so that they have a reduced threshold of nociceptive stimulus following a prior painful stimulus
primary and secondary hyperalgesia

Front 39

Primary hyperalgesia

Back 39

occurs at initial site of injury
affects responsiveness to both mechanical and thermal stimuli
(peripheral sensitization)

Front 40

Secondary hyperalgesia

Back 40

occurs in undamaged areas that surround injury
only response to mechanical stimuli is changed (central sensitization)

Front 41

Allodynia

Back 41

condition in which non-noxious stimulus produces painful response
both central and peripheral components
brush test

Front 42

Neuropathic pain
(def)

Back 42

pain that occurs spontaneously or to hypersensitivity to painful stimuli (hyperalgesia & allodynia)

Front 43

Neuropathic pain
(2 general forms)

Back 43

(1) pain associated with soft tissue damage or with inflammation
can involve both peripheral and central components
(2) pain associated with damage directly to nervous system
can be caused by lesion or neurodegenerative disease
can be peripheral or central

Front 44

CRPS

Back 44

Complex Regional Pain Syndrome
(aka Reflex Sympathetic Dystrophy)
chronic, severe pain due to nerve trauma that can occur following surgery, bone fractures or even MI
mech: increase in sympathetic output to somatic nociceptors increasing their activity
Tx: localized sympathetic block or actual lesions of sympathetic nerve

Front 45

Proprioception
(coducted by)

Back 45

afferents in muscles, specifically muscle spindle fibers and golgi tendon organs

Front 46

Muscle Spindle Fibers
Type Ia afferent (Primary Afferent)

Back 46

rapidly adapting
detect small changes in stretch and velocity of stretch
dynamic response

Front 47

Muscle Spindle Fibers
Type II afferents (secondary afferents)

Back 47

sensitive to level of sustained stretch
firing rate stays proportional to absolute level of stretch
encodes static response

Front 48

Muscle Spindle Fibers
Motor Neurons
gamma

Back 48

smallest
innervate only intrafusal

Front 49

Muscle Spindle Fibers
Motor neurons
alpha

Back 49

largest
innervate only extrafusal

Front 50

Muscle Spindle Fibers
role

Back 50

detect degree of muscle stretch or length

Front 51

Muscle Spindle Fibers
3 components

Back 51

Intrafusal fibers
Sensory endings
Motor neurons

Front 52

Golgi Tendon Organs (GTO)
role

Back 52

detect changes in force produced by extrafusal muscles
respond to muscle contraction
provide constant force when grasping an object or allow compensation for changes in load or increasing fatigue

Front 53

Golgi Tendon Organs (GTO)
location

Back 53

at the point where muscle fibers connect to tendons

Front 54

Golgi Tendon Organs (GTO)
components

Back 54

encapsulated collagen fibers intertwined with axons from Ib afferent fibers