Lecture 5: cont Flashcards
Where are the climbing fibers coming from and which neurotransmitters are used for communication?
Contralateral inferior olivary nuclei
glutamate or aspartate
Parallel fibers are axons of _________ cells
granule
Inhibition vs. Disinhibition:
Parallel fibers activate Purkinje cell and _________/______ cell
Negatively regulated by ________ cell: ______ aspect of signal processing
basket/stellate
Golgi; temporal
Inhibition vs. Disinhibition:
Purkinje cells in flanking zones will be ________ by basket and stellate cells: ______ aspect
Selectively inhibit/dishinbit of nuclei both _______ &______ aspect
inhibited; spatial
temporal and spatial
Regulating Firing Rate of Purkinje cells:
_________ only from inferior olivary nuclei
-complex spike, “calcium spike”
_________synaspe with granule cells —> activate target cells through _______ fibers
Climbing fibers
Mossy fibers; parallel fibers
Climbing and Multilayered fibers are only temporal effects? True or False
False: both temporal and spatial
Regulating Firing Rate of Purkinje cells:
Purkinje cells integrate the spatial and temporal patterns of excitatory and inhibitory inputs from parallel fibers, climbing fibers, and interneurons. This is known as ____________
Spatiotemporal summation
Motor Functions of Vestibulocerebellum:
_______ pathway: Purkinje cells project to vestibular nuclei directly
________descending motor pathway that maintains posture and balance controlling extensor mm. in limbs
________neural pathway involved in coordinating eye movements, gaze and tracking
Direct
lateral vestibulospinaltract (LVST)
medial longitudinal fascicules (MLF)
Motor Functions of Vestibulocerebellum:
_________ pathway: Purkinje cells project to fastigial nuclei
__________ does not directly innervate distal limbs like ________
Directly project to the ________
indirect
bilateral medial vestibulospinal tract (MVST) ; LVST
spinal cord
Primary function of the Vestibulocerebellum:
postural control/balance/coordination of eye movement
How do mossy fibers modulate Purkinje cell functions?
Synapse with granule cells which activate target cells through parallel fibers
Vestibulocerebellum impairment:
What pathway in the brainstem is responsible for coordinating eye movements, specifically CN IiI, IV, and VI?
-Loss of function:
Medial Longitudinal Fascicles (MLF)
loss of smooth pursuit (saccades), nystagmus, diplopia
Vestibulocerebellum impairment:
Vestibulospinal tract (CNS) plays a key role in ___________.
Loss of function can leads to:
Postural control
truncal ataxia, titubation (truncal tremor)
*refer to jeopardy image
Motor function of the spinocerebellum and pathway:
position and movement proximal joints and extremities
afferent through sup. and inf. cerebellar peduncle
Motor function of the cerebrocerebellum and pathway:
-motor planning, initial activation pf primary cortex
-timing of muscle contraction
-precise dexterous movement of extremities
afferent through middle cerebellar peduncle to contralat. hemisphere
What signs will the patient present of fastigial nucleus impaired during SCA stroke?
impaired postural control/ balance, coordination of eye movement
*SCA supplies vestibulocerebellum
*fastigal nucleus located in vestibulocerebellum
Dymestria - hypo/hyper?
Dysdiadochokineasia:
Dysarthia:
hypermetria: overshoot
hypometria: undershoot’
fast supination/pronation
slurred speech
Somatotopy in cerebellum: ________ representation of body on cerebellum
redundant
Somatotopy in cerebellum: Invereted ant. lob and seperated posterior lobe. Explain what is mean.
Inverted ant. lobe: “upside down”, legs and feet represented in superior/upper anterior lobe and arms and hands represented by inferior/lower anterior lobe.
Separated in posterior lobe: limbs movements and maintenance vs. posture/balance
Lost of somatotopy in presentation in cerebropontine tract is more complicated S&S due to
connection of motor cortex to the pons in brainstem: controls voluntary movements (face/tongue)
What is the circuit between the hypothlamus and cerebellum:
________ fibers
________ nervous system- drives, _____/_____/_____/
multilayered
autonomic; fight/fight/rest/digest
L SCA stroke:
Somatomotor deficits:
Visceral motor functional impairments: (2)
L hand intention tremor
Dilation of L pupil; Flush of L face and warm
*both signs are related to activated sympathetic motor
Fastigial nucleus injury: decrease _______ and ________
_______ nerve dominated
heart rate and blood pressure
parasympathetic
How an the cerebellum modulate ipsilateral motor functions?
Superior cerebellar peduncle cross over to contralat. motor cortex but motor cortex goes down ipsilateral side to control same side in CB
The ______ & ________ system of the cerebellum involves emotion and behaviors.
vermis and limbic
What is CCAS:
cerebellar cognitive affective syndrome:
Does the cerebellum involves ALL the functions of the CNS?
Yes
Why cerebellar functional loss is rare?
somatotopy- redundancy in the topography
