modulation of movement by the cerebellum Flashcards
cerebellum is also called what
little brain
what is the primary function of the cerebellum
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).
when can the motor error corrections be done
These corrections can be made both during the course of the movement and as a form of motor learning when the correction is stored
how does the cerebellum influence mvts and balance primarily
by modifying the activity patterns of the upper and lower motor neurons.
what does the cerebral hemispheres divide into
Left and Right ant and post lobes
what is the deep cerebellar nuclei and what 3 nuclei does it divide into
Clusters of cells in nuclei buried deep in the white matter of the cerebellum:
-Fastigial nucleus
-Interposed nuclei
-Dentate nucleus
what are the three cerebellar peduncles
sup, middle and inferior
cerebellar hemispheres can be divided into 3 parts
cerebrocerebellum, spinocerebellum, vestibulocerebellum
describe the cerebrocerebellum (position, receives input from where, function)
-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)
describe the spinocerebellum (position, receives input from where, function of both parts)
-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)
describe the vestibulocerebellum (what lobes does it include, where does it receive its input, involved in reg of what)
-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
The connections between the cerebellum and other parts of the nervous system are made by what
3 large pathways called cerebellar peduncles
the cerebellar peduncles keep the cerebellum attached to what
brainstem
are the peduncles efferent, afferent or both
sup: mainly efferent (output)
middle: afferent pathways (input)
inf: multiple pathways (afferent and efferent)
describe the cortiopontocerebellar pathway
-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
cerebellar cortex neurons project to where
deep cerebellar nuclei (dendate and interposed)
what pathway allows the cerebellum to influence posture and equilibrium (adjusting VCR, VSR, VOR reflexes)
cerebellar-vestibular pathway
The cerebellar-vestibular-cerebellar pathways play a critical role in integrating and modulating vestibular signals to:
-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
what segment of the brain is the most neuron dense
cerebellum/
what cell is the main one in the cerebellum
purkinje cell
Purkinje cells in the cerebellar cortex receive sensory information from the____ _____ and ____ nuclei through the _____ fibers and _____ fibers (excitatory inputs)
inf olive
pontine
mossy
climbing
the cerebellar neurons output to the motor cortex generates what that can modify movements.
an error correction signal
Activity of Purkinje cell and deep cerebellar nuclei cell at rest of the wrist.
At resting state: Both Purkinje cell and deep cerebellar nuclei cell are tonically active.
Activity of Purkinje cell and deep cerebellar nuclei cell during movement of the wrist.
During movement of the wrist (i.e., rapid alternating movements) both cell types receive a transient inhibition that blocks their tonic activity.
what are the higher functions of the cerebellum
-Sensory acquisition,
-Motor attention,
-Timing of motor actions,
-Prediction and preparation of movement,
-Motor sequence learning and memory.
what is the helper structure
cerebellum
cerebellum circuitry could be acting as a ______ and _____ the body movement accordingly. It helps to coordinate motor actions _____
predictor (predicts surrounding movements)
adjusts
unconsciously
how does the cerebellum help in motor coordination
by parallel computations (participates in the integration of motor function)
what is the cerebellum’s role in motor cognition
learning motor sequences,
memory of motor actions
what is the cerebellum’s role in non-motor functions
e.g, the organization and coordination of thought and emotion
