Spinal Cord, Brainstem And Motor Fnx II (Obj. 1 and 2) Flashcards

1
Q

Most fibers of the CBT terminate where?

A
  • In the RETICULAR formation

- Near the Cranial Nerve Nuclei

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

CST Lesions can lead to what?

A
  1. Hyper-Tonia
  2. Hyper-Reflexia
  3. Clonus (Spasm)
  4. Muscle weakness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Rubro-Spinal Tract Characteristics

  • Origin
  • Decussation
  • Descends
  • Responsible for
A
  • Originates in the RED Nucleus
  • Decussates in the MIDBRAIN
  • Descends in LATERAL Column (Funiculus)
  • Responsible for Large Muscle MOVEMENT and some FINE motor movement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Cortico-Bulbar Tract Characteristics

A
  • UMN of the CRANIAL Nerves
  • Innervating the Face, Head, and Neck
  • Contain ASSOCIATION Neurons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The Lateral CST supplies ____ while the Anterior CST supplies _____.

A
  1. All Levels of the Spinal Cord

2. Neck and Upper Limbs

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

What is thought to be the fxn of the Olivo-Spinal Tract?

A
  • Involved into REFLEX movement

- Recent studies have called into question its existence

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

What % of Upper MN decussate in the Pyramidal System and where?

A
  • 75% to 85%

- Decussate in the Pyramids

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

Red Nucleus Projections Stimulate ____ and Inhibit ____.

A
  • Flexors

- Extensors (Anti-gravity)

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

Olivospinal tract originates where?

A

The Medulla in INFERIOR Olivary Nucleus

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

Reticular formation is a network of what?

A
  • Nuclei w/in the Brainstem

- In both the PONS and the Medulla

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

What do the UMN form after decussation?

A

Forms the LATERAL Cortico-Spinal Tracts

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

Effects of Lesions to the Rubro-Spinal Tract

A
  • Impairment of DISTAL Arm and Hand movement
  • Intention Tremors
  • May take over for injured CST in some animals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The Cortico-Spinal Tract is also known as the _____.

A

Pyramidal Tract

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

Lateral VST

A
  • Major part of tract
  • IPSILATERAL
  • Upright posture and Balance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Anterior CS Tract Characteristics

A
  • Made up of UNCROSSED fibers
  • Cross near the level of Synapse with LMN’s
  • Supply NECK and Upper Limbs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Medial VST

A
  • Projects Bilaterally
  • Controls LMN of CN 11
  • Projects Indirectly to CN 6 and 3
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Vestibulo-Spinal Tract Characteristics

  • Originates
  • Goal
  • Descends
  • Synapses
A
  • In the Vestibular Nuclei in the Medulla
    (Receives input from CN8)
  • Maintain BALANCE
  • Descends in ANT. Column (Funiculus)
  • Synapses w/ LMNs to EXTENSOR Muscles
    (Upright Posture)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where does the Pyramidal System upper MN originate?

A

Motor Cortices

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

Red Nucleus

A
  • Evolutionary Primitive portion of the Brain

- Relay Center

20
Q

Components of the Pyramidal system

A
  1. Cortico-SPINAL Tract

2. Cortico-BULBAR Tract

21
Q

What must occur for complete paralysis in CST?

A

If BOTH the Pyramidal and Extrapyramidal systems are involved in the lesions

22
Q

Lesions of the ExP Subcortical Nuclei can lead to what?

A
  • Parkinson’s Disease
  • Side Effects of Anti-Psychotic Drugs
  • Dystonia
23
Q

Do all the fibers in the CS Tract Decussate in the Lower Medulla?

A
  • No only 80%

- Some continue down IPSILATERALLY in ANTERIOR CS Tract where they decussate near the synapse of LMN

24
Q

What is the Pyramidal System?

A
  • Motor Tracts that pass through the MEDULLARY Pyramids
25
Q

Fxn of the Reticulo-Spinal Tract

A
  • Mediates Larger movements of Trunk and Limbs
  • When Standing it excites axial extensors
  • Controls Alpha and Gamma Neurons
  • Mediates Circulatory system and breathing
  • Can modulate PAIN info
26
Q

When do the remaining fibers from the CS Tract decussate?

A

When Exiting the Spinal Cord

27
Q

CBT Lesion Characteristics

A
  • Lesions typically UNILATERAL

- Result in MILD muscle weakness

28
Q

Fxn of the Rubio-Spinal Tract

A

Closely related to Cerebellar Fxn

29
Q

Pathway of the CS Tract

A
Origin
-> Internal Capsule
—> Medullary Pyramids 
——> 80% X in LOWER Medulla (Most)
———> LATERAL Columns of Spinal Cord (Lat. CS Tract)
30
Q

Extrapyramidal means what?

A

Other motor pathways that do NOT pass through the MEDULLARY Pyramids

31
Q

Pontine vs Medullary Reticular Nuclei

A

Pontine

  • Uncrossed
  • Stimulate Flexors and Extensors
  • Maintenance of Movement

Medullary

  • Uncrossed AND Crossed
  • Inhibitory effect on Flexors and Extensors
32
Q

Association Neurons

A
  • Leave RF and synapse in CN Nuclei

- Synapse w/ LOWER MN

33
Q

Extrapyramidal System Tracts include what?

A
  1. Rubro-Spinal
  2. Reticulo-Spinal
  3. Vestibulo-Spinal
  4. Olivo-Spinal

RRVO

34
Q

Most UMN in the Pyramidal system Synapse where?

A

With ASSOCIATION Neurons in the Spinal Cord Central Gray

35
Q

Where do the remainder of the UMN decussate?

What do they form?

A
  • Near the Synapse with the LOWER MN

- Form the ANTERIOR Cortico-Spinal Tracts

36
Q

Extrapyramidal System Characteristics

A
  • This system includes pathways that contribute to motor control but that are not part of the CS system
  • Includes Descending Motor Tracts that do not pass through Medullary Pyramids or CBT
37
Q

NT of Betz cells

A

Glutamate

38
Q

Betz Cells are also known as what?

A

Giant Pyramidal Cells

39
Q

The VST can be divided into what?

A
  • Lateral and Medial VST
40
Q

Lateral CS Tract Characteristics

A
  • Made up of CS Fibers that have crossed in the MEDULLA

- Supply ALL Levels of the Spinal Cord

41
Q

Fxns of the CS Divisions

A
  • Add speed and agility to the conscious movements
    (Especially the Hand)
  • Provides a High degree of Motor Control
    (Especially in the fingers)
42
Q

Projections of the Red Nucleus

A
  1. Rubio-Spinal Tract
    (Contralateral)
  2. Inf. Olive
    (Ipsilateral)
43
Q

What are the Origins of the CS Tract?

A
  1. Primary Motor Cortex (30%)
  2. Premotor Cortex
    (30%)
  3. Somatosensory Area
    (40%)
44
Q

Characteristics of Betz cells

A
  • Large Cells
  • Large fibers
  • Transmit 70m/sec (Fastest in CNS)
  • Make up 3% of fibers in the tract
  • Sends collateral back to Cortex
45
Q

CS Tract Division

A
  1. LATERAL

2. ANTERIOR (Ventral)

46
Q

Where are Betz cells located?

A

In the Motor Cortex