lower motor neuron dysarthria

Etiology

• weakness or paralysis of the articulary muscles
• lesions of the motor nuclei of the pons & medulla
• lesions of the cranial nerve 5, cranial nerve 7, cranial nerve 10, or cranial nerve 12

Epidemiology

less frequent than spastic dysarthria

Clinical manifestations

• in advanced forms, the tongue is shriveled & lies fasciculating on the floor of the mouth
• lips are lax & tremulous
• saliva constantly collects in the mouth because of dysphagia
• drooling is troublesome
• the voice is altered to a monotone because of vocal cord paralysis
• as the condition develops, speech becomes slurred & progressively less distinct
• a special difficulty in the enunciation of r occurs early
• as paralysis becomes more complete, consonants are not pronounced at all
• bilataleral paralysis of the palate causing nasality of speech - diphtheria, polio, progressive bulbar palsy
• bilateral paralysis of the lips - Guillain-Barre syndrome

More general terms

• dysarthria