A disorder of lower motor neurons in the motor areas of the cranial nerves in the brainstem can result in bulbar palsy.
Muscles affected:
(1) jaw
(2) tongue
(3) soft palate
(4) pharynx
(5) larynx
(6) face
Clinical findings in affected muscles:
(1) flaccid paralysis
(2) muscle weakness
(3) muscle atrophy
(4) muscle fasciculations and/or fibrillations
Functions affected:
(1) speaking and articulating (with dysarthria)
(2) chewing (mastication)
(3) swallowing (with dysphagia)
(4) breathing (especially if motor nuclei in the upper spinal cord are affected)
(5) coughing
The presence of emotional lability (emotional incontinence) favors the diagnosis of pseudobulbar palsy (see above).
