Motor Systems - 4/26 Stephens

Question 1

What passes through the posterior limb of the internal capsule?

Answer 1

Corticospinal tract (CST)
Somesthetic fibers
Optic radiations

Question 2

Bell’s Cruciate paralysis results from disruption of what structure?

Characteristics?

Answer 2

Midline involvement of upper pyramidal decussation

Paralysis of the upper extremity WITHOUT lower extremity involvement

Question 3

Bell’s Cruciate palsy may also be caused by damage to what structure?

Answer 3

Dens

Question 4

What deficits are associated with uncrossed corticobulbar fibers?

Answer 4

A3H and A5H

Question 5

Which deficits are associated with crossed corticobulbar fibers?

Answer 5

A6H

Question 6

Unilateral lesion of the corticobulbar fibers above the level of the facial nucleus (anterior portion) results in what?

Symptoms?

Answer 6

Supranuclear facial palsy

Contralateral mimetic muscles on the lower quadrant of the face are paralyzed

Question 7

What are the most common sites for lesions causing supranuclear facial palsy?

Answer 7

Genu of internal capsule

Facial region of motor cortex

Question 8

What is the extrapyramidal system involved in?

Answer 8

Crude, stereotyped, associative movements of the axial and proximal limb musculature

Question 9

Generally describe what the extrapyramidal system does

Answer 9

Swinging arms while walking

Facial grimace while talking

Question 10

The dorsal division of the ansa lenticularis is commonly called what?

Answer 10

Lenticular Fasciculus

DL

Question 11

The ventral division of the ansa lenticularis is called what?

Answer 11

Ansa lenticularis

VA

Question 12

The dorsal and ventral divisions of the ansa lenticularis form what?

Answer 12

Thalamic Fasciculus

Question 13

Nigra-Thalamic fibers are what type?

Originate from where?

Terminate where?

Answer 13

Non-DA

Pars reticularis of SN

VA and VL Thalamic nuclei

Question 14

Where do fibers from the GP and SN terminate of the VL and VA of Thalamic nuclei?

Important for what?

Answer 14

Not in the same region

Stereotaxic surgery for Parkinson’s disease

Question 15

Nigro-striatal fibers are what type?

Originate where?

Terminate where?

Answer 15

DA fibers

Pars compacta of SN

Caudate and Putamen

Question 16

Destruction of what neurons in what area of the brain cause Parkinson’s?

Answer 16

Dopaminergic Nigro-striatal of the pars compacta in SN

Question 17

Destruction of what causes Huntington’s Chorea?

Answer 17

GABAnergic fibers in the striatonigral fibers

Question 18

Unilateral lesions of the subthalamus or its connections results in what?

Characterized by what?

Answer 18

Contralateral hemiballism

Violent, involuntary, flinging movements of the limbs

Question 19

What are the major signs and symptoms of Parkinson’s?

Answer 19

Bradykinesia
Tremor during rest
Rigidity
Masked Face
Postural Embarrassment

Question 20

Most common features of Huntington’s Chorea?

What chromosome is fucked?

Answer 20

Dementia
Chorea
Behavioral disturbances

Short arm Chr. 4

Question 21

Where does the corticobulbar fibers pass through in the brain?

Answer 21

Genu of internal capsule