Contributions of Cerebellum and Basal Nuclei to Motor Function (Lec 8)

Question 1

The primary motor cortex (area 4) of the cerebral cortex, signals motor neurons to contact what?

Answer 1

skeletal muscle fibers

Question 2

The primary motor cortex (area 4) of the cerebral cortex, signals via the ___ tract

Answer 2

corticospinal

Question 3

The execution of commands by the primary motor cortex (area 4) of the cerebral cortex, is preceded by extensive processing by what?

Answer 3

cerebellum and basal nuclei

Question 4

What does the premotor cortex (area 6) of the cerebral cortex do?

Answer 4

plans movements based on sensory and visual cues

Question 5

What does the supplementary motor area (area 6) of the cerebral cortex do?

Answer 5

retrieves and coordinates memorized motor sequences

Question 6

What are the functions of the motor cortex system of the cerebral cortex?

Answer 6

provides most of activating signals to spinal cord; issues sequential and parallel commands that initiate various cord patterns; cortical patterns are usually complex and can be learned; cord patterns are mainly determined by heredity and are “hard wired”

Question 7

This part of the brain plays major roles in the timing of motor activities and in rapid, smooth progression from one muscle movement to the next

Answer 7

cerebellum

Question 8

True or false?

The cerebellum is essential for locomotion

Answer 8

false; not essential

Question 9

True or false?

The cerebellum learns by its mistakes

Answer 9

true

Question 10

The cerebellum functions with the spinal cord to enhance what reflex?

Answer 10

stretch reflex

Question 11

The cerebellum functions with brain stem to make what type of movements?

Answer 11

postural

Question 12

The cerebellum functions with the cerebral cortex to provide what?

Answer 12

accessory motor functions

Question 13

True or false?

The cerebellum turns on antagonist at appropriate time.

Answer 13

true

Question 14

This type of nuclei help to plan and control complex patterns of muscle movement, controlling relative intensities of the separate movements, directions of movements, and sequencing of multiple successive and parallel movements

Answer 14

basal nuclei

Question 15

Basal nuclei plan and execute motor commands in concert with the cerebral cortex, this helping execute what?

Answer 15

subconscious but learned patterns

Question 16

True or false?

Basal nuclei control complex patterns of motor activity?

Answer 16

true

Question 17

True or false?

electrical excitation of the cerebellum does not cause any conscious sensation and rarely causes any motor movement

Answer 17

true

Question 18

True or false?

removal of the cerebellum does not cause any body movements to become abnormal

Answer 18

false, causes abnormal body movement

Question 19

In regards to the anatomical organization of the cerebellum, the two hemispheres are separated by what?

Answer 19

vermis

Question 20

In regards to the anatomical organization of the cerebellum, each hemisphere is divided into two zones. What are they?

Answer 20

intermediate and lateral zones

Question 21

In regards to the anatomical organization of the cerebellum, there are three lobes. What are they?

Answer 21

anterior, posterior, flocculondular lobes

Question 22

The vermis is the location for control functions for muscle movements of what?

Answer 22

axial body, neck, shoulders, and hips

Question 23

This zone of the cerebellum is concerned with controlling muscle contractions in the distal portions of the upper and lower limbs, esp. hands, feet, fingers, and toes

Answer 23

intermediate zone

Question 24

What is the lateral zone associated with and what is its function?

Answer 24

associated with cerebral cortex with planning of sequential motor movements

Question 25

In regards to gray matter of the cerebellum, the cortex consists of transversely arranged narrow gyro called what?

Answer 25

folia

Question 26

What do lesions in dentate nuclei, emboliform nuclei, and globose nuclei cause?

Answer 26

extremity ataxia

Question 27

Where do fibers from dentate nuclei, emboliform nuclei, and globose nuclei project?

Answer 27

to the red nucleus

Question 28

Dentate nuclei, emboliform nuclei, and globose nuclei are related to what type of musculature and movement?

Answer 28

limb musculature and fine manipulative movement

Question 29

What do lesions in fastigial nuclei cause?

Answer 29

trunk ataxia

Question 30

Where do fibers from fastigial nuclei project?

Answer 30

reticular formation and vestibular nuclei

Question 31

Fastigial nuclei are related to what type of activity and movement?

Answer 31

postural activity and limb movements via reticulospinal and vestibulospinal tracts

Question 32

Axons from parallel fibers in cortex (+) are made up of what the of cells?

Answer 32

granular cells

Question 33

This type of cell projects from parallel fibers to granular cell bodies (-)

Answer 33

golgi cells

Question 34

Basket cells project from parallel fibers to where?

Answer 34

purkinje axon hillock (-)

Question 35

Stellate cells project from parallel fibers to where?

Answer 35

purkinje dendrites (-)

Question 36

This type of cell shows extensive dendritic branching, receives input from parallel fibers, projects to intracerebellar nuclei (-), and serves as only output from cerebellar cortex

Answer 36

purkinje cells

Question 37

Each functional unit of the cerebellar cortex is centered on a purkinje cell and a corresponding ___ ___ cell

Answer 37

deep nuclear

Question 38

True or false?

output from a fictional unit is from a purkinje cell

Answer 38

false; deep nuclear cell

Question 39

Afferent inputs to the cerebellum are mainly from what?

Answer 39

the climbing and mossy fibers

Question 40

Where do all climbing fibers originate?

Answer 40

the inferior olives

Question 41

Mossy fibers send excitatory collaterals to deep nuclear cells and then synapse where?

Answer 41

in granular layer with thousands of granule cells

Question 42

Granule cells send axons where?

Answer 42

to outer cerebellar surface

note: axons branch in two directions parallel to folia

Question 43

Direct stimulation by climbing and mossy fibers excites what?

Answer 43

deep nuclear cells

Question 44

What inhibits deep nuclear cells?

Answer 44

parking cell signals

Question 45

True or false?

Basket cells and stellate cells are activating cells

Answer 45

false; inhibitory