2B. Motor System - Upper Motor Division

Question 1

Neurons that make muscles contract are defined as:

Answer 1

Lower Motor Neurons (LMN)

Question 2

Neurons that regulate LMNs are defined as:

Answer 2

Upper Motor Neuron (UMN)

Question 3

The pyramidal motor system can also be called a cortical motor system because the motor neuron cell bodies are located in the______________

Answer 3

cerebral cortex

Question 4

• Regulates the LMN activity that results in Highly skilled motor activity usually with a direct synapse on the LMN
• includes discretely organized, interconnected white matter structures formed by axons that pass through the pyramids

Answer 4

Cortical Motor System (Pyramidal Motor System)

Question 5

• regulates the LMN activity that is responsible for muscle tone, coarse or stereotyped movements, and SUBCONSCIOUS motor activity
• includes motor centers scattered in each division of the brain with axons that are NOT associated with the formation of pyramids

Answer 5

Non-Cortical Motor System = Extrapyramidal Motor System

Question 6

Anatomy of Pyramidal Motor System
- Cell bodies located in the pre- and post cruciate gyri depending on the species
- Descending axons from the cell bodies contribute to the formation of discretely organized and identifiable bundles of White Matter

Answer 6

Motor Cortex (cell bodies)

Question 7

Tracts of the Pyramidal System
- From the pyramidal motor cortex (cortico-) to LMN nuclei (-nuclear) in the BRAINSTEM of cranial nerves III-VII and IX-XII

Answer 7

Corticonuclear System

Question 8

Tracts of the Pyramidal System
- from the pyramidal motor cortex to LMN in the spinal cord
- LATERAL corticospinal tract: 75% of the pyramidal fibers will CROSS over to the opposite side and descend CONTRALATERAL to find the appropriate motor neuron at the appropriate level of the SPINAL CORD
- VENTRAL corticospinal tract: 25% are going to descend IPSILATERALLY (same side) through the rest of the brainstem and then cross at the appropriate level of the spinal cord to regulate lower motor neurons in the ventral GRAY MATTER COLUMN

Answer 8

Corticospinal System

Question 9

Tracts of the Pyramidal System
Where is the cord location for Corticospinal Fibers?

Answer 9

Lateral and Ventral FUNiculus

Question 10

What is the role of the Cerebellum?

Answer 10

Is to produce smoothly coordinated movement
(cerebellar input from Pyramidal motor system)

Question 11

A neuron that has its cell body and axon both located in the brain and spinal cord:

Answer 11

is an Upper Motor Neuron

Question 12

Which of the following is an example of a component that is part of the non-cortical motor system?

Answer 12

Putamen

Question 13

A tract of nerve fibers or a path for nerve impulses that pass from the Cerebral Cortex through the Internal Capsule to the Pons to the White Matter and Cortex of the Cerebellum

Answer 13

Corticopontocerebellar tract

Question 14

What system do these functions describe?
- gravity, muscle, posture
- Subconscious movement (stereotyped)
- NOT in the Pyramids
- LMN regulation
- All over-the-place components
- Major UMN system for animals

Answer 14

Extrapyramidal System

Question 15

Anatomy of the Extrapyramidal Motor System
- an area of the TELENCEPHALON (Cerebrum) under the surface of the cortex (subcortical) formed by alternating bundles of white matter and extrapyramidal motor nuclei

Answer 15

Corpus Striatum

Question 16

Telencephalon Extrapyramidal motor area: Corpus Striatum
- External Capsule = ______________
- Lentiform Nucleus: 2 nuclei-gray matter
- ________________ (lateral)
- ________________ (globus pallidus, medial)
- Internal Capsule = White Matter
- Caudate nucleus = Gray Matter

Answer 16

• White Matter
• Putamen
• Pallidum

Question 17

Anatomy of the Extrapyramidal Motor System
- Various nuclei where synapses occur along within the system

Answer 17

Diencephalon

Question 18

Anatomy of the Extrapyramidal Motor System
- Rubrospinal Tract: Most important extrapyramidal center in animals
- Origin: Red Nucleus
- Location: Rubrospinal tract in lateral FUniculus of the spinal cord for LMN regulation

Answer 18

Mesencephalon

Question 19

What is the most important extrapyramidal center in animals?

Answer 19

Rubrospinal Tract

Question 20

Anatomy of the Extrapyramidal Motor System
- Pontine reticulospinal tract (excitatory), facilitates extensor muscles
- Origin: pontine reticular formation
- Location: pontine reticulospinal tract, also called the VENTRAL reticulospinal tract

Answer 20

Metencephalon

Question 21

Anatomy of the Extrapyramidal Motor System
- Medullary Reticulospinal Tract (inhibitory), inhibits extensor muscles
- Origin: Medullary reticular formation
- Location: Medullary reticulospinal tract, also called the LATERAL reticulospinal tract

Answer 21

Myelencephalon

Question 22

Is important because it represents how the extrapyramidal system sends information to the cerebellum

Answer 22

Olive

Question 23

The ______________ acts to take all of the motor information, and blend it with the sensory information, to produce smooth coordinated movement

Answer 23

Cerebellum

Question 24

• Extrapyramidal information synapses in the olivary nucleus in the medulla and enters the cerebellum through the Caudal Cerebellar Peduncle

Answer 24

Olivocerebellar Fibers

Question 25

What are the Hallmark Signs of an Upper Motor problem?

Answer 25

• HypeRReflexia
• Hypertonus
• Spastic Paralysis
• Slow muscular atrophy over time from disuse of muscles

Question 26

Which of the following is part of the pyramidal motor system?
- caudate nucleus
- medullary reticulospinal tract
- pallidum
- crus cerbri

Answer 26

Crus Cerebri

Question 27

Neurons that give rise to the pyramidal motor system have their cell body located in the:

Answer 27

Cerebral cortex

Question 28

The Corticonuclear Tract is part of the __________________ motor system

Answer 28

pyramidal