Physio Ii Test 3: Neuro Lectures 1-2

Front 1

Transduction

Back 1

process by which a stimulus is converted into physiology useful information

Front 2

Adaptation

Back 2

describes the decrease in the response of a sensory receptor during a continuously applied stimulus.

Front 3

grated response of receptor potential

Back 3

the amplitude of the receptor potential increases with increasing stimulus intensity over a wide range.

Front 4

adaptation occurs for 2 reasons

Back 4

1) structural changes in the receptor itself (e.g. Pacininian corpsuscle)
2) accommodation in the sensory ending.

Front 5

generator potential

Back 5

-a specific type of receptor potential involving the depolarization of primary sensory endings produced by a stimulus. Leads to APs in the primary afferent fiber if depolarizations are large enough.

Front 6

Receptor potential

Back 6

the change in membrane potential of the receptor as a result of the interaction with the stimulus.
a)several mechanisms
b)graded response
decremental conduction

Front 7

what receptor is poor at detecting duration?

Back 7

Rapidly adapting receptors (RAR)

Front 8

What receptors are good at determining rate of change of stimulus (when the stimulus changes)?

Back 8

Rapidly adapting receptors (RAR)

Front 9

cold receptors axons

Back 9

1)mylelinated A delta
2)some C fibers

Front 10

warm receptors axons

Back 10

axons are C fibers

Front 11

nuclear bag fibers

Back 11

-intrafusal fibers which connect numerous nuclei packed in a center bag area.
-Dynamite receptors-sense rate of change in muscle lengthe

Front 12

nuclear chain fibers

Back 12

-shorter thinner intrafusal fibers containing a single row of nuclei.
-static receptors-report static muscle length

Front 13

Two reasons adaptation happens in receptors?

Back 13

-structural changes in the receptor itself (pacinian corpuscle)
-accommodation in the sensory ending

Front 14

Labeled line

Back 14

the way modality is accomplished by the wiring of the nerve to the CNS

Front 15

intensity of stimulus

Back 15

can be coded by:
-frequency of AP
-# of sensory afferents
-types of sensory receptors

Front 16

frequency of stimulus

Back 16

-interval btwn AP
-interval btwn beginning of each burst of AP

Front 17

Duration in slowly adapting sensory neurons?

Back 17

-duration of enhanced activity

Front 18

Duration in rapidly adapting sensory neurons?

Back 18

-transient discharge at the beginning and end of the stimulus (unreliable bc cannot tell difference btwn one long and two short ones)

Front 19

Which mechanoreceptors are rapidly adapting?

Back 19

Meissner's corpuscle and Pacininian corpuscle

Front 20

Which mechanoreceptors are slowly adapting?

Back 20

Merkel receptor and Ruffini ending

Front 21

Which mechanoreceptors are both rapidly and slowly adapting?

Back 21

hair follicle receptors and free nerve endings

Front 22

Which mechanoreceptors are nonencapsulated?

Back 22

-Merkel receptor,
-free nerve ending
-hair follicle receptor

Front 23

Hair follicle receptor

Back 23

-nonencapsulated
-found in hairy skin
-slowly + rapidly adapting
-detect light touch

Front 24

meissner's corpusle

Back 24

-encapsulated
-superficial layer of glabrous (hairless) skin (esp. fingertips)
-rapidily adapting
-respond well to low frequency (20-50Hz)
-small receptor fields for fine tactile discrimination

Front 25

Merkel receptor

Back 25

-nonencapsulated
-slowly adapting
-small receptor fields
-sense pressure and aids in fine tactile discrimination

Front 26

Pacinian corpuscle

Back 26

-encapsulated
-widespread distribution in deep dermal layers
-slowly adapting
-large receptor fields, most sensitive to vibrations of 200 to 300Hz

Front 27

Ruffini ending

Back 27

-encapsulated
-widespread distribution in deep dermal layers
-slowly adapting
-large receptor fields, of unknown function, perhaps pressure

Front 28

free nerve endings

Back 28

-nonencapsulated
-found all over body
-both rapidly and slowly adapting
nondiscriminatory (crude) touch and pressure

Front 29

What type of axon fibers are cold receptors?

Back 29

-mostly myelinated A(delta) but some C fibers

Front 30

What type of axon fibers are warm receptors?

Back 30

-C fibers

Front 31

What type of noxious stimuli do A(delta) fibers mediate?

Back 31

-fast, sharp, localized pain

Front 32

What type of noxious stimuli do C fibers mediate?

Back 32

slow, aching, diffuse pain

Front 33

features common to all spinal reflex

Back 33

-sensory receptor
-afferent (sensory) fiber
-CNS
-efferent (motor) fiber
-effector (muscle or gland)

Front 34

annulospiral endings

Back 34

-located on intrafusal fibers
-involved in knee jerk reflex

Front 35

the knee jerk reflex is also known as what?

Back 35

phasic reflex

Front 36

The inverse stretch reflex is also known as what?

Back 36

inverse myotactic

Front 37

What happens to the afferent fibers in both the stretch and inverse stretch reflex?

Back 37

-They branch as they enter the spinal cord and one branch ascends to contribute information to cerebellum and cerebrum about motor control and proprioception.

Front 38

Decrebrate rigidity

Back 38

-transection of brain stem at level of superior and inferior colliculus (descending pathways from cerebral cortex are disrupted)
-increase in EXTENSOR tone bc inhibitory influence is removed and motor output increases
-also known as y-rigidity

Front 39

Where are nociceptors not found?

Back 39

in parenchyma of internal organs (including brain)

Front 40

Classes of nociceptors?

Back 40

-thermal (A(delta), sharp, fast pain)
-polymodal (mechanical, chemocicl or temp, C fibers, slow dull late pain)

Front 41

Receptors that inform the brain about a rate in change of a stimulus.

Back 41

Rapidly adapting/phasic receptors

Front 42

receptor that is poor at determining duration of stimulus

Back 42

Rapidly adapting/phasic receptors

Front 43

receptors that shut off with sustained stimuli.

Back 43

Rapidly adapting/phasic receptors

Front 44

"slip receptors"

Back 44

Meissner's corpuscle

rapidly adapting/phasic receptors

Front 45

"grab receptors"

Back 45

Merkel receptors

slowly adapting/tonic receptors

Front 46

2 small receptive field receptors

Back 46

Meissner corpuscle and Merkel receptor

Front 47

2 receptors found in high concentration in the finger tips that are responsible for discriminatory touch (fine tactile discrimination).

Back 47

Meissner corpuscle and Merkel receptor

Front 48

T/F Encapsulated receptors are responsible for discriminatory touch (fine tactile discrimination)

Back 48

False
Meissner corpuscle-encapsulated

Merkel receptor-nonencapsulated

Front 49

group I

Back 49

Aα

Front 50

group II

Back 50

Aβ

Front 51

group III

Back 51

Aδ

Front 52

group IV

Back 52

C fiber

Front 53

What sets the sensitivity of the muscle spindle fiber?

Back 53

gamma motoneurons

Front 54

T/F the receptor for the inverse stretch receptor is the muscle spindle

Back 54

F, The inverse stretch reflex is the golgi tendon organ

Front 55

Knee jerk reflex

Back 55

-AP in Ia produce monosynaptic excitation of alpha-motorneurons
-reciprocal innervation
-y-mototneurons maintain tension of intrafusal fibers and sensitivity of extrafusal
-co-activation of alpha and gamma motoneurons

Front 56

inverse stretch reflex

Back 56

-Golgi tendon organ receptor
-reports MUSCLE TENSION
-group Ib fibers inbibit A(alpha) and excite antagonistic muscle

Front 57

Describe receptor potentials

Back 57

-graded response- amplitude of receptor potential increased with increasing stimulus intensity over a wide range
-decremental conduction

Front 58

Thermoreceptors

Back 58

-free nerve endings
-spontaneously active
-slowly adapting but discharge phasically when temperature is changed