Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

OT 441: Neuroscience - Summer 2017 > Intro to Motor Control: Lower Motor Neurons (9) EXAM 3 Material > Flashcards

Intro to Motor Control: Lower Motor Neurons (9) EXAM 3 Material Flashcards

1
Q

T or F: Movement is meaningful and motivated?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

T or F: Movement is best understood by looking at the interaction of the person, task and environment?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What environments is movement guided by?

A

Internal and External

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Do none, some, or all nervous system components influence movement?

A

All nervous system components

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What type of movement happens when a doctor taps your knee and it pops up?

A

Reflex/Reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What type of movement happens when you touch something hot and jerk your arm back?

A

Reflex/reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Reflex/reaction

A

Occurs as a reaction to something

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is volitional movement?

A

With intention

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What two types of volitional movement are there?

A
  1. Automatic

2. Cortical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is cortical movement?

A

Requires conscious attention (like when learning to ride bike)
(Part of volitional movement)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is automatic movement?

A

Requires little conscious attention, but does require continuous integration of information
(Part of volitional movement)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where do spinal nerves exit?

A

Above/below the vertebrae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

T or F: the Spinal cord is the same in different regions?

A

F, the spinal cord is NOT the same in different regions: Shape, size, proportion of white-to-gray matter change.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where are motor neurons in the spinal cord?

A

Ventral horn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Internal Divisions of the spinal cord: Gray Matter areas

A

Dorsal Horn, Ventral Horn (motor neurons are in ventral horn)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Internal Divisions of the spinal cord: White Matter areas

A

Location of ascending and descending tracts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Do the tracts in the spinal cord ascend in white or gray matter?

A

White matter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Medial descending tracts of the spinal cord control what muscles?

A

Axial muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Lateral descending tracts of the spinal cord control what muscles?

A

Distal muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Lower Motor neurons directly innervate what?

A

Skeletal muscle fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where are the cell bodies of LMN’s located?

A

In the SC or brainstem (CN’s)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where do the upper motor neurons synapse?

A

On the LMN’s and/or interneurons in the brainstem or SC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Why do the UMN’s synapse on the LMNs or interneurons?

A

In order to convey commands for movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Where do cell bodies of UMN’s originate?

A

Higher regions of the brain (cortex or brainstem)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What type of neuron are LMNs?

A

Multipolar (many dendrites)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Do many or little neurons synapse w the LMN’s?

A

Many (from higher centers and spinal afferents)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Once outside the vertebral column LMNs are part of the CNS or PNS?

A

PNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Which are the ONLY neurons that send signals to extrafusal and intrafustal skeletal muscle fibers?

A

Lower motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Two types of LMNs:

A
  1. Alpha

2. Gamma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Alpha LMN:

A

Projects to extrafusal skeletal muscle, branching into many terminals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Where are the cell bodies of alpha and gamma LMNs?

A

In the ventral horn of the spinal cord (gray matter)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Gamma LMN:

A

Projects to intrafusal fibers of the muscle spindle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are groups of LMNs in the SC whose axons project to a single muscle?

A

LMN pools

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Neurons to a specific muscle are NEAR or FAR from each other in the ventral horn?

A

NEAR

ex: flexor muscle neurons would be together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Medial LMN Pools:

A

Axial/proximal muscles (head, neck)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Lateral LMN Pools:

A

Distal Muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Ventral LMN Pools:

A

Extensors (ex: triceps)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Dorsal LMN Pools:

A

Flexors (ex: biceps)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Which “pool” area of the ventral horn controls extensor muscles?

A

Ventral LMN pools

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Which “pool” area of the ventral horn controls distal muscles such as the fingers?

A

Lateral LMN pools

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Which “pool” area of the ventral horn controls the head and neck muscles?

A

Medial LMN pools

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Which “pool” area of the ventral horn controls the flexor muscles?

A

Dorsal LMN pool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

How many nerves supply each skeletal muscle?

A

One or more

44
Q

What kind of fibers do nerves contain?

A

Both motor and sensory

45
Q

An alpha motor neuron and all the muscle fibers it innervates

A

Motor unit

46
Q

Motor unit can be:

A

Fast twitch or slow twitch

47
Q

Fast Twitch

A

Faster speed of contraction (alpha motor neuron)

ex: gastrocnemius muscle when sprinting

48
Q

Slow Twitch

A

Slower speed of contraction (alpha motor neuron)

ex: Trunk muscles

49
Q

Innervation ratio:

A

The number of muscle fibers innervated by a single LMN

50
Q

Example of low innervation ratio:

A

Eye, (one neuron to two muscle fibers for precision)

51
Q

Example of high innervation ratio:

A

Calf (one neuron to hundreds of muscle fibers, not for precision)

52
Q

End plate of neuromuscular junction

A

Highly excitable region of the muscle fiber’s membrane responsible for the initiation of AP’s across the muscle’s surface, causing the muscle to contract

53
Q

Motor Neuron Lesion: Muscle Strength

A

Decreased ability to generate muscle force

54
Q

Partial loss of voluntary muscle contraction

A

Paresis

55
Q

Complete loss of voluntary muscle contraction

A

Paralysis

56
Q

Hemiplegia

A

One side of the body experiences muscle loss (line down center of body)

57
Q

Paraplegia

A

lower half of body paralyzed

58
Q

Quadriplegia/Tetraplegia

A

paralysis of all four limbs

59
Q

Atrophy

A

Loss of muscle bulk, wasting

60
Q

Two types of atrophy:

A
  1. Disuse

2. Neurogenic

61
Q

Disuse atrophy:

A

Type of decreased muscle bulk, person CHOOSES not to use muscles, but can

62
Q

Neurogenic Atrophy:

A

Type of decreased muscle bulk due to motor neuron lesion. CANT recruit muscles in this atrophy .

63
Q

Which happens faster, Neurogenic or Disuse atrophy?

A

Neurogenic because pathway is blocked.

64
Q

Consequences of Motor Neuron lesions: (6 things)

A 
Muscle Strength
Muscle bulk
Muscle contraction
Muscle tone
Muscle stiffness
Reflexes
65
Q

Muscle Tone

A

The force with which a resting muscle resists being stretched (also termed stiffness)

66
Q

Range of muscle tone:

A

Normal, Hypotonia, Hypertonia

67
Q

What does normal muscle tone allow for?

A

Maintenance of posture

68
Q

Hypotonia

A

Abnormally low resistance to passive stretch (flaccidity)

69
Q

How does hypotonia occur?

A

LMN lesions
Acute LMN lesion (ex: Stroke)
developmental disorders

70
Q

Hypertonia

A

Atypically strong resistance to passive stretch; greater than normal muscle tension

71
Q

Two types of hypertonia:

A

Spastic

Rigid

72
Q

Which type of hypertonia is velocity dependent?

A

Spastic

if you try and move someone’s muscle slowly there is a better movement possibility than if you try and jerk it quickly

73
Q

Which type of hypertonia is velocity independent?

A

Rigid

doesnt matter how fast or slow you try and move someone’s muscle

74
Q

What does hypertonia occur from?

A

Chronic UMN lesion (stroke)

Some Basal Ganglia disorders (Parkinson’s)

75
Q

Signs of a LMN disorder:

A

Muscles undergo:

  1. Wasting/atrophy
  2. Fasciculations
  3. Fibrillations (detectable by myography)
  4. Flaccid paralysis
  5. Loss of reflexes
76
Q

Etiology of Polio (Poliomyelitis):

A

Viral illness: transmitted primarily through the ingestion of material contaminated with fecal matter.

77
Q

Pathology of Polio:

A

Virus leaves digestion track and enters the blood stream, attacking the LMNs (in spinal cord and brainstem)

78
Q

Asymptomatic Polio:

A

No symptoms (most people had this one)

79
Q

Symptomatic Polio:

A

Symptoms range from mild to severe (death possible)

80
Q

Spinal Polio:

A

LMN cell bodies attacked (only in ventral horn of spinal cord)

81
Q

Bulbar polio:

A

CN (motor) cell bodies attacked (in brainstem)

82
Q

Bulbospinal polio:

A

Combination of spinal polio and bulbar polio where cell bodies are attacked in spinal cord and in brainstem.

83
Q

Polio: Axonal Sprouting

A

Survivors of polio recover some muscle strength as surviving neurons sprout new terminal axons and innervated the denervated muscle fibers.
(Mainly in bulbar polio)

84
Q

Collateral Sprouting:

A

Sending off a shoot from a healthy axon

85
Q

Iron Lung

A

Allows a person to breathe when normal muscle control has been lost or the work of breathing exceeds the person’s ability.

86
Q

Post-Polio syndrome possible symptoms:

A

Muscle weakness and atrophy
Joint and muscle pain
Fatigue
Breathing and swallowing problems

87
Q

When does Post-Polio syndrome occur?

A

Years (decades) after the acute illness in some people who survive paralytic polio

88
Q

Theory of post-polio syndrome:

A

Due to overextending of surviving neurons
Use it and (you will) lose it.
(wouldnt want to tell your patient to go to the gym and overexert)

89
Q

ALS: Inherited or idiopathic?

A

Both, 1 in 10 cases is inherited, the others are idiopathic (dont know why you get it)

90
Q

What does ALS cause the destruction of?

A

Somatic motor neurons (bilateral)

UMNs and LMNs

91
Q

What is the progression in regards to muscles of ALS symptoms?

A

Progressive muscle weakness and atrophy –> paralysis
(Paresis, spasticity, hyperreflexia (overresponsive reflexes), atrophy, fasciculations (brief, spontaneous contraction of only a few muscle fibers) )

92
Q

What is the LMN damage in regards to ALS?

A

CN damage, difficulty with breathing, swallowing and speaking

93
Q

Prognosis of ALS:

A

Average life span following diagnosis is 3 years, usually caused by respiratory complications.

94
Q

Myopathic Disorder

A

A disorder intrinsic to muscle

95
Q

Duchenne’s Muscular Dystrophy:

A

Genetic disorder, X-linked

96
Q

Duchenne’s Muscular Dystrophy: occurs mostly in girls or boys?

A

Boys (almost exclusively occurs in boys)

97
Q

What is the most common form of childhood muscular dystrophy?

A

Duchenne’s

98
Q

What is the cause of Duchenne’s Muscular Dystrophy?

A

A genetic deficiency of the protein dystrophin

Without dystrophin, muscles are not able to operate properly and will eventually suffer progressive damage.

99
Q

Early symptoms of Duchenne’s MD:

A 
Clumsy movement
Difficulty climbing stairs
Frequently trips and falls
Unable to jump or hop normally
Tip toe walking
Gower's Sign
100
Q

What is Gower’s Sign?

A

An early symptom of Duchenne’s MD where the person has difficulty getting up from a sitting or lying position on the floor.

101
Q

Why would you see enlarged calf muscles in Duchenne’s MD?

A

Due to large amounts of fatty deposits that are replacing muscle.

102
Q

What type of condition is Duchennes MD? (progressive, stable, etc..)

A

Progressive, first affects the muscles of the legs and pelvis, then progresses to the arms, neck and other areas of the body

103
Q

When is a wheelchair usually needed by in Duchennes MD?

A

By age 12

104
Q

By late teens, what happens in Duchennes MD?

A

Often have heart and lung problems

105
Q

What happens to the sensory and autonomic functions in Duchennes MD?

A

Remain intact.

OT 441: Neuroscience - Summer 2017 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions