kinesthesia

Question 1

_____ is the perception of movement and position of limbs and other body parts such as jaw movements

Answer 1

Kinesthesia

Question 2

_______ are specialized interoceptors that are used to transduce the initial kinesthetic information

Answer 2

Proprioceptors

Question 3

compare type A, B, and C proprioceptors!

Answer 3

-Type A: fastest, largest, myelinated
-Type B: middle for speed and size
-Type C: smallest, slowest, unmyelinated

Question 4

Explain the differences between the A subtypes (alpha, Ia, Ib, Aβ, Aγ)

Answer 4

-Aα → motor to skeletal muscle
-Ia → sensory to muscle spindles
-Ib → sensory to tendon organs
-Aβ → II → sensory for touch, pressure, muscle spindles
-Aγ → motor to intrafusal fibers

Question 5

which of the proprioceptors are for motor?

Answer 5

Aα, Aγ

Question 6

Type B proprioceptors transduce _____ information for PRE-ganglions

Answer 6

autonomic

Question 7

what are the two types of C proprioceptors?

Answer 7

C, C(IV)

Question 8

how do the different C proprioceptors differ in what they transduce?

Answer 8

-C: autonomic for post-ganglionic
-CIV: sensory for pain/temp

Question 9

________ are on the outside of a muscle spindle while _________ are on the inside of a muscle spindle

Answer 9

Extrafusal muscle fibers, Intrafusal muscle fibers

Question 10

Extrafusal muscle fibers are innervated by ___ neurons and intrafusal muscle fibers are inntervated by ______

Answer 10

1. α motor neurons
2. Group 1 and 2 (Aα, Aβ), Aγ

Question 11

is there afferent sensory innervation of extrafusal muscle fibers?

Answer 11

NO!

Question 12

______ wrap around the center of muscle fibers and
______ are near the end of muscle spindle fibers

Answer 12

Ia fiber,
II fibers

Question 13

____ fibers carry stretch (static or tonic) and velocity (dynamic or phasic) sensation, while ___ fibers carry static only.

Answer 13

Ia, II

Question 14

in which fibers does the Firing rate increases when muscle moves and decrease when muscle stops?

Answer 14

1a

Question 15

in which fibers does the firing rate increases linearly as muscle rate increases with stretch ?

Answer 15

II

Question 16

______ innervate extrafusal fibers, the highly contracting fibers that supply the muscle with its power while ________ innervate intrafusal fibers, which contract only slightly.

Answer 16

alpha motor neurons
Gamma motor neurons

Question 17

______ is when a skeletal muscle contracts involuntarily when suddenly stretched by an external force (passive stretch)

Answer 17

Stretch (myotatic) reflex:

Question 18

which motor neurons fire in response to Ia input in a stretch reflex?

Answer 18

alpha

Question 19

a stretch reflex is considered ______ because only one neuron-neuron synapse exists in the arc

Answer 19

monosynaptic

Question 20

does a stretch reflex have interneurons?

Answer 20

no

Question 21

understand the arc of a stretch reflex

Answer 21

Question 22

When muscle ______, muscle spindle gets lax

Answer 22

contracts

Question 23

______ activate to contract spindle and take up the slack

Answer 23

Gamma motor neurons

Question 24

what is gamma bias? what controls it?

Answer 24

gamma bias is the gain of the response to stretch, gamma motor neurons

Question 25

To prevent muscles from opposing each other,______ motor neurons of the opposing muscle are inhibited by the same ___ signal

Answer 25

alpha, 1a

Question 26

_______senses muscle force

Answer 26

golgi tendon organ

Question 27

The _________ prevents muscle and tendon tears from too much force

Answer 27

Golgi tendon reflex

Question 28

explain the golgi tendon reflex

Answer 28

1. Ib afferent from muscle → CNS 2. Ib inhibitory interneuron → IPSP to flexor muscle (ex: bicep) 3. Separate EPSP to extensor muscle to bring back flexor muscle from edge (ex: tricep)

Question 29

muscle spindles in parallel sense _____, GTO in serial sense ________

Answer 29

muscle length, muscle force

Question 30

what does the dorsal column pathway/medial lemniscal pathway sense?

Answer 30

Light touch, proprioception, vibration

Question 31

what are the three neurons for the lower body portion of the dorsal column pathway?

Answer 31

1. 1st order neuron = dorsal root ganglia -Feeds into the dorsal horn of spinal cord and transcends up PNS 2. 2nd order neuron = gracile nucleus -CNS 3. 3rd order neuron = ventral posterior lateral (VPL) -In the thalamus (CNS)

Question 32

what are the three neurons for the upper body portion of the dorsal column pathway?

Answer 32

1st order neuron = Dorsal root ganglion 2nd order neuron = Cuneate nucleus 3rd order neuron = ventral posterior lateral (VPL)

Question 33

After the 2nd order neuron for both upper and lower body, _______ occurs, then it goes to VPL

Answer 33

crossing over (decussation)

Question 34

what is the non-head internal proprioception pathway and how does it compare to dorsal column?

Answer 34

Pretty much same as dorsal column pathway, except there is also the spinocerebellar pathway (for anything T1 and below)

Question 35

T1 and below = DRG first synapses on________(in Clarke's nucleus) then collaterals up spinocerebellar and dorsal column tract

Answer 35

spinocerebellar neuron

Question 36

explain the pathway of the spinocerebellar pathway

Answer 36

1. Signal comes from DRG 2. Synapses on spinocerebellar tract neuron which goes up to cerebellum (cerebellum is in control of unconscious control of balance) 3. It also relays to normal sensory nucleus (cuneatus and gracilis) so that it can go to thalamus and the brain knows what the rest of your body is doing

Question 37

what are the neurons for the Trigeminothalamic pathway for the head?

Answer 37

1. 1st order neuron = come in through trigeminal nerve, but bypass trigeminal ganglion, go to mesencephalic nucleus *** 2. 2nd order neuron = principle nucleus of TG complex 3. 3rd order neuron = ventral posterior medial (VPM) - In thalamus

Question 38

explain the jaw-closing reflex

Answer 38

1. 1a receptors in muscle spindles in the masseter go through Masseteric n., → past trigeminal ganglion → to mesencephalic nucleus 2. Collateral goes down to Motor nucleus of V → sends message out with Alpha motor neuron to masseter to contract and close 3. Collateral goes up to VPM in brain to tell the brain what is going on

Question 39

in the jaw opening reflex, the _____ is inhibited

Answer 39

temporal muscle

Question 40

_____ is the state of tension that muscles are always in

Answer 40

Tone

Question 41

_____ input from muscle spindle keeps the muscles in a state of readiness to resist stretch

Answer 41

Static fiber

Question 42

Hypotonia is a decrease in muscle tone that results from loss of _____ or_______connection

Answer 42

alpha motor neuron, spindle afferent

Question 43

_____ is an increase in muscle tone due to loss of modulation from brain centers

Answer 43

Hypertonia