Motor

Question 1

What is somatotopic organization?

Answer 1

Certain area of the primary motor cortex controls movement of a specific part of the body

Question 2

True or false: the primary motor cortex is homotopically connected to the opposite hemisphere.

Answer 2

True; both sides are connected to the other side that controls the same thing

Question 3

What do lateral tracts (in descending motor pathways) control?

Answer 3

Independent limb movement

Question 4

What do ventromedial tracts (in descending motor pathways) control?

Answer 4

Automatic, gross movements of trunk and core; proximal limb stability; limbs involved in posture and walking

Question 5

What are the lateral tracts?

Answer 5

Corticospinal tract, corticobulbar tract, rubrospinal tract

Question 6

What are the ventromedial tracts?

Answer 6

Ventral corticospinal tract, tectospinal tract, vestibulospinal tract, reticulospinal tract

Question 7

Where does the corticospinal tract originate and where does it end?

Answer 7

It originates in the cortex (primary and supplementary motor cortex), down to pyramids in medulla, and terminates in gray matter of spinal cord

Question 8

What does the corticospinal tract control?

Answer 8

Primarily fingers, hands, arms, lower legs, feet, and toes

Question 9

Where does the corticobulbar tract originate and where does it end?

Answer 9

Originates primary from primary and supplementary motor cortex; cross in medulla, terminates in cranial nerve

Question 10

What does the corticobulbar tract control?

Answer 10

Primarily movement of face, neck, and tongue; some eye movements

Question 11

Where does the rubrospinal originate and where does it end?

Answer 11

Originates in red nucleus, into dorsal column, and exits on the area of spinal cord according to which area of the body it controls

Question 12

What does the rubrospinal tract control?

Answer 12

Proximal limb movements of forearm and hands, but not finger movements

Question 13

Where does the ventral corticospinal tract originate and where does it end?

Answer 13

Originates primary from primary and supplementary motor cortex; divides in spinal cord and projects bilaterally

Question 14

What does the ventral corticospinal tract control?

Answer 14

Controls trunk (core muscles) and upper leg movements; involved in posture, walking, balance

Question 15

Where does the tectospinal tract originate and where does it end?

Answer 15

Originates in superior colliculus (in tectum), descends and exits through bilateral areas of spinal cord

Question 16

What does the tectospinal tract control?

Answer 16

Controls trunk movements and coordinates them with head movements

Question 17

True or false: the ventromedial motor pathway is a unilateral system.

Answer 17

False; it is a bilateral system; for its muscle groups, the R hemisphere will control both sides of the body

Question 18

Where does the vestibulospinal tract originate and where does it end?

Answer 18

Originates from vestibular nuclei, bilateral exit through spinal cord to trunk

Question 19

What does the vestibulospinal tract control?

Answer 19

Gets input from semicircular canals that give info about head alignment; important for posture, reflexes, and walking

Question 20

Where does the reticulospinal tract originate and where does it end?

Answer 20

Originates from multiple areas: reticular formation, premotor cortex, amygdala, hypothalamus and basal ganglia; ends throughout brainstem

Question 21

What does the reticulospinal tract control?

Answer 21

Controls autonomic functions: muscle tone, coughing, sneezing, respiration; also volitional movements such as walking

Question 22

What is the motor association cortex?

Answer 22

Premotor and supplementary motor area; receives the highest level of integrated sensory info from the parietal and temporal multimodal sensory association areas

Question 23

What is the supplementary motor area?

Answer 23

Involved in learning and programming of sequenced movements; when one movement serves as cue for the next movement

Question 24

What is the pre-supplementary motor area?

Answer 24

Involved in initiating the intention of movement

Question 25

What is the premotor cortex?

Answer 25

Involved in learning and executing complex movements that are guided by sensory input; important when sensory input is “arbitrary” i.e., not directly related to the movement

Question 26

What is apraxia?

Answer 26

Preserved ability to move but impairment in complex execution of movements; can be movement of wrong part of limb, incorrect movement of correct limb, or correct movements in incorrect sequence

Question 27

What part of the brain is almost always associated with apraxia?

Answer 27

L hemisphere lesions; L parietal or L frontal (plans to move); L frontal will also impair ability to comprehend gestures of others

Question 28

What is the neostriatum?

Answer 28

The caudate and putamen; in the basal ganglia

Question 29

What does the cerebellum influence?

Answer 29

Postural reflexes; rapid, skilled multi-muscle movements; modification/regulation of movements initiated in cortex; timing and sequencing of movements

Question 30

What symptoms are produced by lesions in the cerebellum?

Answer 30

(dependent on area) rigidity, fragmented movement, impaired timing, ataxia