Term
| Where does VOR and OKN processing occur? |
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Definition
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Term
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Definition
| if a cochlear canal is excited, a slow phase drift towards the opposite side. Nystagmums --> working side; Drift --> broken side |
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Term
| Where do reflexive saccades originate in the brain? |
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Definition
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Term
| What neurologic stream is shut off during a saccade? |
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Definition
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Term
| In NSUCO (and other saccades), what is an expected amount of dysmetria? |
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Definition
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Term
| Which hemisphere is reading typically processed in ? |
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Definition
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Term
| What is the average saccadic latency time? |
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Definition
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Term
| What is the breakdown of the ~250 ms saccadic latency time? |
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Definition
100 ms = calculate direction and magnitude of voluntary saccade
50 ms = afferent signal reaching cortex
100 ms = actual eye movement |
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Term
| What neurologic centers maintain gaze fixation? |
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Definition
neural integration in the pons for horizontal fixation in the medial vestibular nucleus and nucleus prepositus hypoglossi
midbrain for vertical fixation by the interstitial nucleus of Cajal (INC) in the midbrain |
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Term
| What are common causes of square wave jerk type saccades? |
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Definition
basal ganglia dz (Parkinson)
Cerebellar Dz (MS)
Meth
Dyslexia
Psychiatric disorders (meds?)
Strabismic amblyopia |
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Term
| What is damaged when square wave jerks are present? |
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Definition
Frontal Eye Fields
Superior Colliculus
Central Mesenphalic Reticular Formation |
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Term
| What causes macro square wave jerks? |
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Definition
| GABA fails to inhibit the SC due to substantia nigra pars reticulata failure |
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Term
| What ALWAYS causes true opsoclonus? |
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Definition
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