progressive bulbar palsy

Progressive bulbar palsy (PBP) is a subtype of amyotrophic lateral sclerosis (ALS), a progressive neurodegenerative disease. PBP specifically results from the degeneration of cranial nerves and the brainstem. The term "bulbar" refers to the medulla oblongata, a part of the brainstem that resembles a bulb.12

Damage to these bulbar nerves impairs functions such as swallowing, speech, and chewing. Individuals may experience a nasal tone to their voice, weakness in neck muscles, and difficulty clearing secretions, which can lead to choking or aspiration. Involuntary emotional outbursts, like laughing or crying, can also occur. The prognosis for this form of ALS is considered particularly grave.21