The life expectancy for someone with progressive bulbar palsy ranges from six months to three years following the onset of symptoms of the disease, according to the Motor Neurone Disease Association. About one-quarter of diagnoses of motor neuron diseases are diagnoses of bulbar palsy.
PBP affects both the upper and lower motor neuron, notes the National Institute of Neurological Disorders and Stroke. Symptoms of PBP include difficulty swallowing, slurring of speech, weakened facial and jaw muscles and tongue muscle atrophy. Abnormalities in the legs and arms are also associated with PBP. This type of disease affects the brain stem and the neurons that are necessary for chewing, speaking, swallowing and other bodily functions.