modulation of movement by the cerebellum

Question 1

cerebellum is also called what

Answer 1

little brain

Question 2

what is the primary function of the cerebellum

Answer 2

detect the difference, or “motor error,” between an intended movement and the actual movement to reduce the error (i.e., if there is a discrepancy, the cerebellum can modify motor signals to correct any errors).

Question 3

when can the motor error corrections be done

Answer 3

These corrections can be made both during the course of the movement and as a form of motor learning when the correction is stored

Question 4

how does the cerebellum influence mvts and balance primarily

Answer 4

by modifying the activity patterns of the upper and lower motor neurons.

Question 5

what does the cerebral hemispheres divide into

Answer 5

Left and Right ant and post lobes

Question 6

what is the deep cerebellar nuclei and what 3 nuclei does it divide into

Answer 6

Clusters of cells in nuclei buried deep in the white matter of the cerebellum:
-Fastigial nucleus
-Interposed nuclei
-Dentate nucleus

Question 7

what are the three cerebellar peduncles

Answer 7

sup, middle and inferior

Question 8

cerebellar hemispheres can be divided into 3 parts

Answer 8

cerebrocerebellum, spinocerebellum, vestibulocerebellum

Question 9

describe the cerebrocerebellum (position, receives input from where, function)

Answer 9

-Most lateral part of cerebellar hemisphere.
-Receives indirect input from many areas of the cerebral cortex.
-Planning, coordination and execution of complex spatial and temporal sequences of movement.
-Cognitive functions (e.g., timing, attention, sensation monitoring, motor learning)

Question 10

describe the spinocerebellum (position, receives input from where, function of both parts)

Answer 10

-median zone
-Receives direct input from the spinal cord (proprioceptive information).
-Monitoring of ongoing movements (i.e., position of the body in space).
-Vermis is involved with (movement of the proximal m. or trunk muscles, movement of eyes)
-Paramedian zone is involved with (movement of distal muscles like arm & leg muscles)

Question 11

describe the vestibulocerebellum (what lobes does it include, where does it receive its input, involved in reg of what)

Answer 11

-caudal-inf lobe of the cerebellum and included nodulus and flocculus
-receives input from vestibular nuclei in the brainstem
-involved in ref of mvt that maintain posture, balance and equilibrium

Question 12

The connections between the cerebellum and other parts of the nervous system are made by what

Answer 12

3 large pathways called cerebellar peduncles

Question 13

the cerebellar peduncles keep the cerebellum attached to what

Answer 13

brainstem

Question 14

are the peduncles efferent, afferent or both

Answer 14

sup: mainly efferent (output)
middle: afferent pathways (input)
inf: multiple pathways (afferent and efferent)

Question 15

describe the cortiopontocerebellar pathway

Answer 15

-Transmits information from motor, premotor cortex, somatosensory
cortex via the pontine nuclei.
-The pathway enters the cerebellum through the middle cerebellar
peduncle. Fibers decussate (i.e., cross to the other side).
-Projects mostly to the lateral areas: Cerebrocerebellum

Question 16

cerebellar cortex neurons project to where

Answer 16

deep cerebellar nuclei (dendate and interposed)

Question 17

what pathway allows the cerebellum to influence posture and equilibrium (adjusting VCR, VSR, VOR reflexes)

Answer 17

cerebellar-vestibular pathway

Question 18

The cerebellar-vestibular-cerebellar pathways play a critical role in integrating and modulating vestibular signals to:

Answer 18

-Enable adaptive changes to the VCR,
-Distinguish head tilts from
translational movements,
-Distinguish passive movements of the head and body from those that are self-generated

Question 19

what segment of the brain is the most neuron dense

Answer 19

cerebellum/

Question 20

what cell is the main one in the cerebellum

Answer 20

purkinje cell

Question 21

Purkinje cells in the cerebellar cortex receive sensory information from the____ _____ and ____ nuclei through the _____ fibers and _____ fibers (excitatory inputs)

Answer 21

inf olive
pontine
mossy
climbing

Question 22

the cerebellar neurons output to the motor cortex generates what that can modify movements.

Answer 22

an error correction signal

Question 23

Activity of Purkinje cell and deep cerebellar nuclei cell at rest of the wrist.

Answer 23

At resting state: Both Purkinje cell and deep cerebellar nuclei cell are tonically active.

Question 24

Activity of Purkinje cell and deep cerebellar nuclei cell during movement of the wrist.

Answer 24

During movement of the wrist (i.e., rapid alternating movements) both cell types receive a transient inhibition that blocks their tonic activity.

Question 25

what are the higher functions of the cerebellum

Answer 25

-Sensory acquisition,
-Motor attention,
-Timing of motor actions,
-Prediction and preparation of movement,
-Motor sequence learning and memory.

Question 26

what is the helper structure

Answer 26

cerebellum

Question 27

cerebellum circuitry could be acting as a ______ and _____ the body movement accordingly. It helps to coordinate motor actions _____

Answer 27

predictor (predicts surrounding movements)
adjusts
unconsciously

Question 28

how does the cerebellum help in motor coordination

Answer 28

by parallel computations (participates in the integration of motor function)

Question 29

what is the cerebellum’s role in motor cognition

Answer 29

learning motor sequences,
memory of motor actions

Question 30

what is the cerebellum’s role in non-motor functions

Answer 30

e.g, the organization and coordination of thought and emotion