Test 4 - Ch. 15 Flashcards
What are the jobs intended for the cerebellum?
Coordinate movement and postural control
Compare what you do to what you meant to do
Makes corrections if necessary
Which section of the cerebellum takes into account the intended movement?
photocerebellar - intended
location - straight back from cerebellum
Which section of the cerebellum takes into account what is actually occurring in movement?
spinocerebellar - actual
location - SC - cerebellum
Where does corrector information get sent if need be from the cerebellum?
from top of cerebellum to UMN of BS and cortex for postural and distal movements
UMN of BS and cortex that control gross postural movements and fine distal movements
What are four areas that the cerebellum gets input from to combine to make corrections?
SC - spinocerebellar - discriminative touch and nonconformist prop (what I am doing)
Reticular formation - arousal (level of urgency)
Vestibular system
Pontine nuclei - xerox copy from cerebral cortex to pons into cerebellar (what I meant to do)
What is the pathway of the output for cerebellar
purkinje to
base of cerebellum to
deep cerebellar nuclei (WM) to
UMN of BS and cortex (gross and fine motor)
Describe the divisions of the cerebellum?
midline vermis
paranormal
lateral
Midline vermis- midline anatomical piece- controls the midline of us (the axial skeleton)
Paravermal hemispheres- those are going to especially
control out most proximal joints (shoulders and hips)
Lateral hemispheres- those control our distal muscles.
What does the Flocculonodular lobe do?
helps us to maintain our equilibrium overall. (not a vertical division, it plays with vertical divisions)
What does the inferior peduncle of the cerebellum do?
the most inferior fiber bundle, the closest to the spinal cord, brings input from the spinal cord and the brainstem- brings the message of what I am really doing.
What does the middle peduncle of the cerebellum do?
big one- brings input from the pontine nuclei- the xerox copy- what I meant to do message
What does the superior peduncle of the cerebellum do?
fiber bundle- takes messages up to BS and cortex make corrections if necessary
What are the three functional divisions of cerebellum?
Vestibulocerebellum- Flocculonodular lobe - balance and equilibrium
Spinocerebellum - Vermis and paravermis - BS UMN core and prom
Cerebrocerebellum - Lateral hemispheres - corticospinal - fine movements distal
What does the vestibulocerebellum do?
represents inner ear. Has a real tight connection to the inner ear. (balance and equilibrium)
Input- from the inner ear (vestibular receptors)
Output- from the cerebellum through the vestibular nuclei to eye muscles and postural muscles a steady gaze is critical to equilibrium so that we stay balanced.
Function- equilibrium
What does the spinocerebellum do?
tight connection to the brainstem UMN) (core and proximal)
Input- spinocerebellar tracts (discriminative touch and nonconscious proprioception) and also from sensorimotor cortex (what I meant to do)
needs to know what we are really doing and what we meant to do (so we know if proximal muscles are doing what we want them to do)
Output- Medial division UMN
cerebral cortex- medial corticospinal neurons (voluntary control)
brainstem- medial and lateral vestibulospinal (medial-keeps head upright against pull of gravity, lateral-keep lower body upright against gravity) and reticulospinal
Function- control core and proximal movements.
What does the cerebrocerebellum too?
lateral corticospinal- strong connection between the cerebellar hemispheres (fine motor control)
Input- cerebral cortex (cerebropontocerebellar, from the head to the pons to the cerebellum-the xerox copy)- and sends planning messages back
Output- lateral division UMN
Cerebral cortex
Function- coordinate voluntary movement
- plan movements - timing
Discuss aspects of nonconcious spinocerebellar pathways.
What I am really doing
Collapse all of cerebellar input into name of spinocerebellar (discriminative touch and nonconscious proprioception headed to the cerebellum) grossly tells us where it comes from and where it is going
- 2 high fidelity- highly detailed body mapping
- each pathway has 2 neurons- one peripheral and one central
- Somatosensory input from body (discriminative touch and nonconscious proprioception)
- project to cerebellum ipsilaterally (take sensory info from one side of the body to the cerebellum on the same side of the body) cerebellum in cortex takes care of the crossing
As a group called spinocerebellar pathways.
How does ataxia from cerebellar injury present? ataxia vestibucerebellum spinocerebellum cerebrocerebellum
Damage to cerebellum produces signs on same side as damage (left and left, right and right)
verbal and floculonodular :Ataxia- incoordination not due to muscle weakness
vestibulocerebellum- truncal ataxia- have a hard time controlling trunk itself
spinocerebellum- gait ataxia- hard time coordinating my trunk over my hips- always chasing Base of support somewhere cerebrocerebellar- hand ataxia- hard time coordinating movements of the hands.
What would damage to Paravermis and hemisphere present as?
dysarthria
What would spinocerebellar damage present as?
Ataxic gait- unsteady, veering, staggering gate. (usually a compensation. Problems with proximal joint control and leads to these signs we would see.
Limb ataxia-
Dysdiadochokinesia- alternating reversing movements that have a rhythm, to switch direction
test- rapidly pronate and supinate, may have trouble rapidly controlling their supination and pronation. F
or legs, tapping, can you keep the rhythm up. Suggests damage to the spinocerebellum
Dysmetria- impaired ability to accurately hit a target.
Metria- ability to accurately hit a target
Action (intention tremor)- tremor when I move and I oscillate back and forth around a joint or a limb. (overcorrection hones in and eventually gets finger to the target.
leg=put heel on knee or slide heel down your shin.
Decompose movements- have trouble controlling things (especially multiple joints at the same time) robot like in their movements=focus on one joint at a time.
treatment can be to decompose movements to focus on one joint and simplify what the brain has to control and makes us better at doing the motion/task.
Move slow, move consciously, maximize sensory input, treatment= see what you are doing, simplify movements, move slower, think about what you are doing.
How would cerebrocerebeallar damage present?
trouble with fine coordination- trouble manipulating and controlling buttons on remote or trouble threading a needle
How are cerebellar and somatosensory ataxia different?
cerebellar - give all sensory inout but no ability to process
will still have issues even if eyes are open
somatosensory - have eyes and sway
