There are several other neurogenic disorders that may affect the larynx and in turn, affect voice quality. In many cases, these neurogenic voice disorders will be accompanied by other speech and swallowing difficulties such as dysarthria, dysphagia, apraxia, aphasia, and other cognitive difficulties. Resonance may also be affected by neurogenic disorders. The range and type of neurologic voice problems that may occur are extremely varied and each case may present with a different degree of dysphonia and accompanying disorders. Some of the diseases that may cause voice disorders include (but are not limited to): myasthenia gravis, multiple sclerosis (MS), Parkinson’s Disease, Amyotrophic Lateral Sclerosis (ALS), Huntington’s Chorea, progressive bulbar palsy. The treatment options for voice therapy (and other therapies) differ depending on the effects the individual diseases have on the respiratory, phonatory, and resonance systems in an individual patient.