View source for Nuclear and supranuclear lesions

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* Nuclear lesion (bulbar palsy)
** = bilateral lesion of the motor nucleus of a cranial nerve, its axon, or its NMJ
** Pathophysiology
*** Cranial nerves IX, X, XI, and XII are affected
*** Equals a “lower motor neuron” lesion, with typical peripheral motor lesion symptoms like atrophy and flaccidity
** Clinical features
*** Normal facial expressions (because VII is unaffected)
*** Nasal speech
*** Dysphagia of fluids
*** Atrophic and fasciculating tongue
*** Absent gag reflex
* Supranuclear lesion (pseudobulbar palsy)
** = bilateral lesion of the corticobulbar tracts
** Pathophysiology
*** Cranial nerves V, VII, IX, X, XI, XII are affected
*** Equals an “upper motor neuron” lesion, with typical central motor lesion symptoms like spasticity and hyperreflexia
** Clinical features
*** Stiff, spastic facial muscles -> no facial expressions
*** Spastic dysarthria (Donald Duck voice)
*** Dysphagia
*** Spastic tongue
*** Pseudobulbar affect/emotional incontinence
**** Uncontrollable laughing or crying
**** Think Joaquin Phoenix in the Joker
*** CN V palsy -> exaggerated jaw jerk reflex
*** Brisk gag reflex
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[[Category:Neurology]]