57.2 Flashcards
(10 cards)
Where does the corticopontocerebellar pathway start and end?
It starts in the motor, premotor, and sensory areas of the cerebral cortex, passes through the pontine nuclei, and ends in the lateral hemisphere of the opposite side of the cerebellum.
What is the origin and target of the olivocerebellar tract and what activates it?
It originates from the inferior olive, which is activated by the motor cortex, basal ganglia, spinal cord, and reticular formation, and sends signals to all parts of the cerebellum.
Where do vestibulocerebellar fibers come from and what do they control?
They come from the vestibular system in the inner ear and the vestibular nuclei in the brainstem, and mainly go to the flocculonodular lobe and fastigial nucleus to help with balance.
Where do reticulocerebellar fibers originate and what is their function?
They originate from the reticular formation of the brainstem and go mainly to the vermis to help with posture and body tone.
What sensory information does the dorsal spinocerebellar tract carry and where does it go?
It carries info from muscle spindles, Golgi tendon organs, touch receptors, and joint receptors, enters through the inferior cerebellar peduncle, and ends in the vermis and intermediate zone on the same side.
What is unique about the ventral spinocerebellar tract and what does it carry?
It carries an efference copy of motor commands from motor pathways and spinal pattern generators, enters through the superior cerebellar peduncle, and ends on both sides of the cerebellum.
How fast are signals in the spinocerebellar tracts and why is that important?
They travel up to 120 m/sec, which is the fastest in the nervous system, allowing the cerebellum to stay instantly updated.
What are other peripheral input routes to the cerebellum besides spinocerebellar tracts?
They include pathways through the dorsal columns to the medulla and the spinoreticular and spino-olivary tracts.
What are the three deep cerebellar nuclei and what else acts like one?
Dentate, interposed, and fastigial nuclei, with the vestibular nuclei in the medulla also acting like deep nuclei.
How is input to the cerebellum divided and processed?
One part goes to a deep nucleus directly, and the other to the overlying cortex, which sends a delayed inhibitory signal to the same nucleus for fine-tuned control.
