Cerebellum Lec22 Flashcards
what are the deep nuclei in the vermis?
fastigial n.
vestibular n.

motor function of the vermis and fastigial?
balance, eye movement, reflexes
cogntiive function of the fastigial and vestibular n. ?
autonomic arousal, limbic regulation
Nulcei in the paravermal hemisphere?
globose and emboliform

moor function of the globose and emboliform (intemediate paravermal hemisphere)?
sensorimotor integration, movement execution
sensory function of the ** globose and emboliform ** hemisphere (intemediate paravermal hemisphere)?
simple verbal
responses to commands
nuclei in the lateral hemisphere?
dentate

motot function of the dentate gyrus?
prepration and planning of movement
fine motor dexterity
eye movements
imagined movements
cognitive function of thedentate gyrus
verbal associaiton
rule based learning
working memory
problem solving
monitoring performance
temporal perception
main inputs into the cerebellum? (3)
- cerebrocerebellum: frontal and parietal
- vestibular nuclei
- spinocerebellar

where does the frontal/parietal lobes contribute to?
mostly the lateral hemispheres (think planning movements)

where does the spinal cord input to in the cerebellum?
vermis/some hemisphere

where do the vestibular nuclei input to in the cerebellum?
into the nodulus/flocculus

What is the cerebellum (in terms of cellular components)
The cerebellum = cerebellar cortex + deep nuclei + white matter tracts
How many layers does the cerebellar cortex have? what are they?
3 layers: Molecular, Purkinje cell, and Granule cell

The cell bodies of most mossy fibers entering the cerebellum are located in the ____
pons
The expansion of the lateral cerebellar hemisphere in humans indicates that the cerebellum is capable of ___
contributing to more than just motor function
___ shows prominent activation during
extremely difficult problem solving tasks in humans?
Dentate nucleus
The appearance of oscillating movements of the hand while reaching toward a target is
referred to as ___
intention tremor
The use of ethanol to control symptoms of essential tremor is effective because ethanol (2)
- inhibits normal excitation
- facilitates GABAergic function
which cerebellar n. is involved in
autonomic arousal, limbic regulation
fastigal and vestibular
which cerebellar n. is involved in
simple verbal respponses to commands
globose and emboliform
which cerebellar n. is involved in
rule based learning, problem solving, temporal perception etc
dentate
which cerebellar n. is involved in
preparation and planning of movements
dentate
which cerebellar n. is involved in
sensoriomotr integration, movement ececution
globlose and emboliform
where are radial (bergmann) glial cells found
in the purkinje and moelcular layers of the cerebellar cortex
where are bushy astroglia found
in the granule layer
where are olgiodendrocytes found
in the white matter
where do purkinje cells project to
the deep cerebellar nuclei

____ - wrap around one Purkinje cell
Climbing fibers

Mossy fibers - synapse with one ___ cell
granule

inputs to mossy fibers
pontine nuclei
reticular formation
spinal cord
vestibular nuclei
purkinje cell has ___ input on the deep cerebellar nuclei
gaba
climbing fibers gets input from the
inferior olive
input to purkinje
inferior olive (via climbing fibers)
granule cells (via parallel)
cortical neurons (basket, stellate)

what cells are located in the purkinje layer
purkinje
basket
stellate
what cells are located in the granular layer
golgi
granule
what do granule cells project to
(other cerebellar cortical cells)
purkinje
basket
stellate
golgi
input to granule layer
pontine and brainstem nuclei via mossy fibers
granule cells are excitatory or inhibitory
excitatory
purkinje are inhbhitory or excitateory
inhibitory
parvocellular Red Nucleus inputs into the
inferior olive

magnocellular Red Nucleus gets input from the
deep nuclei
deep nuclei project to
red nucleus
thalamus
cortex (eventually)
interneurons

deep nuclei ___ the thalamus and motor cortex
stimulate

the purkinje layer is ___ on the dentate nucleus
inhibiotry

2 types of APs in the cerebellum
simple and complex spikes
Simple spikes - normal action potentials with ___ depolarization and repolarization
rapid
___ spikes are elated to moment-to-moment changes in behavior, including “efference copy”
simple
simple spikes are produced by ___ fiber activation
mossy fiber
mossy fibers –> Granule cells –> parallel fibers –> Purkinje cells
___ is expected information coming back from the same body part used
reafference
Complex spikes - ____ depolarizations of 20+ milliseconds
extended
Complex spikes - extended depolarizations of 20+ milliseconds, during which time about___ action potentials are fired,
5
triggered by ____ fibers from the inferior olive
climbing
complex spikes are related to
unexpected stimuli / error signals
what is the cellular basis for cerebellar learnign
long term depresion
after and during a __ spike, the purkinje cell is refractory to parallel fiber activation
complex
after and during a complex spike, the ___ cell is refractory to parallel fiber activation
purkinje
after and during a complex spike, the purkinje cell is refractory to parallel fiber activation which is ____
long term depression
rapid learning.. e.g. error signal alerts you to destabilization, then reflex could shut of.. this rapid learning needs the ___
cerebellum
cerebellar lesions leads to what triad?
Asthenia (loss of muscle strength)
Atonia (loss of muscle tone)
and Ataxia (problem with executing voluntary movements)
Asynergia: difficulty ___ muscular actions
coordinating
Decomposition of movement: complex actions broken down into
single joint
actions
___: poorly directed movements that often miss their targets
Dsymetria
___ speech: staccato and problematic articulation
Scanning
Cerebellum has both motor and non-motor outputs!
lesion of PICA –> no motor symptoms, but failures in ___
rule-based language tasks
seen.
nonmotor functions of the cerebellum
language, verbal working memory, sequence learning, error detection,
explicit memory retrieval, planning, classical conditioning
Mild to moderate damage, the cerebellum
resets and compensates on its own
Severe damage, can only give
palliative/supportive care
Essential Tremors (ET) can be treated by ___ or ___
alcohol/barbituates or deep brain
stimulation
for tx of essential tremor, alcohol acts as a ___ and a ___
glutamate anatagonist
and a gaba agonist

Cerebellar insults include (4) disorders
chronic dilantin medication, autism, schizophrenia, chronic
alcohol abuse / thiamine deficiency
what excitatory inputs/output on to the depe nuclei does alcohol effect
inferior olive imnput
and output to the thalamus
what inhibitory inputs/output on to the depe nuclei does alcohol effect
gaba to deep nuclei
atxia is a generalized disorder of
coordianting and excuting voltunary movements
Deviation from the line of movement: movement doesn’t
follow the shortest line
between 2 points
there are multiple representations of different body parts
across the cerebellum showing that the cerebellum has
somatopy
the cerebellum uses error signals to ____ commands for mvoement to optimize outcomes
adaptively modify
Lesion lateral rectus of one eye, then patch good eye
–> Error signal generated
Cerebellum turns up gain from bad eye –> Increased signal / eye gets stronger
Lesions of cerebellum produce IMPAIRMENTS IN ___ of movements and other functions,
QUALITY
Lesions of cerebellum produce IMPAIRMENTS IN QUALITY of movements and other functions, but not a
loss of function.