Motor lectures 5-6

What do signals travel through to get to the cerebellum?

cerebellar peduncles

What are 2 type of functional input to the cerebellum?

Proprioception and UMN input

Are mossy and climbing fibers excitatory or inhibitory?

Excitatory

Are mossy and climbing fibers inputs or outputs to the cerebellum?

Inputs

What do mossy and climbing fibers contact?

Both deep nuclei and cerebellar cortical cells

Where do mossy fibers terminate?

Granule neurons

Where do climbing fibers terminate?

Purkinje cell dendrites

What are the neurons in the deep cerebellar nuclei depolarized by?

Cerebellar inputs

What is the only output from the cerebellum?

Purkinje axon

Where do Purkinje axons go to?

Deep cerebellar nuclei

Is the Purkinje axon inhibitory or excitatory?

Inhibitory

Where do the fibers from deep cerebellar nuclei project to?

Brainstem

What is the function of the cerebellum?

Regulates motor activity, coordinates motor function, inhibits LMN facilitation of antigravity extensor muscles

Does the cerebellum initiate motor function?

No

Does dysfunction result in paralysis?

No

What section of the brain is the caudate in?

Telencephalon

What makes up the corpus striatum?

Basal nuclei and internal capsule

How does information flow through basal nuclei?

Cerebral cortex (motor) to caudate (substantial nigra goes here) to putamen/globus pallidus to thalamus back to motor cerebral cortex

How does the CNS control voluntary motor function?

LMNs

What do UMN systems control?

LMNs

What modulates cortical initiation of voluntary movement?

Basal nuclei

What are the components of gait?

postural phase and swing phase

Does facilitation of antigravity extensors describe postural phase or swing phase?

postural phase

What happens in swing phase 1?

facilitation of flexors to initiate movemet, inhibition of extensors

What happens in swing phase 2?

extensors to complete movement

What tract is involved in the postural phase?

pontine reticulospinal tract

Which phase is the body support?

postural phase

What tract is involved in swing 1?

medullary reticulospinal, rubrospinal tracts

What tract is involved in swing 2?

pontine reticulospinal

Which phase does limb elevation happen?

Swing 1

Is cerebellar disease ataxia or paresis?

ataxia

When does physiological nystagmus occur?

in response to head movement

When does pathological nystagmus occur?

When the head is steady

Which cranial nerve is involved in peripheral vestibular disease?

CN 8

What happens during peripheral vestibular disease?

head tilt, pathological nystagmus

What nuclei is involved in central vestibular disease?

vestibular nuclei

What kind of lesion is it if it has little effect on locomotion and has mild motor signs with possible circling?

motor cortex, basal nuclei lesions

What kind of leasion is it if it has CN deficitys, general proprioceptive defecits, and UMN signs?

brainstem lesion

What kind of lesion is it if it has ataxia, tremor, hypermetria, spasticity, and no paresesis?

cerebellar lesion