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Flashcards in 5. Motor System Deck (20)
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1

Where does the upper motor neuron in the corticobulbar tract end?

Brain stem
Cranial nerve nuclei

2

Where does the upper motor neuron in the corticospinal tract end?

Spinal cord

3

Give the pathway of the pyramidal system

1. Motor cortex
2. Genu/ posterior limb of internal capsule
3. Cerebral peduncles
4. Pons
5. 85% decussate in pyramids of medulla, lateral corticospinal tracts
15% remain in anterior corticospinal tracts

4

What is an example of a disease which causes upper motor neuron lesion?

Stroke

5

Which side in relation to the lesion do symptoms appear after an upper motor neuron lesion?

Contralateral if in cerebral hemisphere
Ipsilateral if in spinal cord

6

What are the signs of an upper motor neuron lesion?

Initial weakness/paralysis
Later spasticity
Hyperreflexia
Clonus
Babinski's sign

7

What is clonus?

When a tendon is stretched, the attached muscle contracts rhythmically

8

What is a positive Babinski sign?

Toes extend when the side of the foot is touched

9

What are the symptoms of a lower motor neuron lesion?

Ipsilateral: Weakness
Muscle wasting
Fasciculations
Hypotonicity
Hyporeflexia

10

What disease causes lower motor neuron lesions?

Polio

11

Which cranial nerves have motor functions?

3, 4, 5c, 6, 7, 9, 10

12

What does an upper motor neuron of the facial nerve lead to?

Bilateral innervation means drooping only occurs below eyes

13

What does an lower motor neuron of the facial nerve lead to?

Facial muscles are damaged above and below the eye

14

Describe the rubrospinal pathway

1. Cerebellum and cerebral cortex to red nucleus
2. Ventral tegmental decussation
3. Enter lateral white column of the spinal cord
4. Gives stimulation to alpha and gamma motor neurons within the ventral grey horn
5. Supply flexors

15

What reflex does the tectospinal tract control?

Response to visual stimuli

16

What does the vestibulospinal tract control?

Tone of extensor muscles
Maintains posture

17

Where is the tectum positioned?

Midbrain
Posterior to aqueduct of Sylvius

18

What are the functions of the tectum?

Superior colliculus: reflex to vision
Inferior colliculus: reflex to sound

19

Where is the tegmentum found?

Anterior to aqueduct of Sylvius

20

What pathways are within the tegmentum?

Homeostatic
Reflexive