Furthermore, according to ASHA, organic dysphonia can be subdivided into structural and neurogenic; neurogenic dysphonia is defined as impaired functioning of the vocal structure due to a neurological problem (in the central nervous system or peripheral nervous system); in contrast, structural dysphonia is defined as impaired functioning of the vocal mechanism that is caused by some sort of physical change (e.g. a lesion on the vocal folds). Notably, an additional subcategory of functional dysphonia recognized by professionals is psychogenic dysphonia, which can be defined as a type of voice disorder that has no known cause and can be presumed to be a product of some sort of psychological stressors in ones environment. It is important to note that these types are not mutually exclusive and much overlap occurs. For example, Muscle Tension Dysphonia (MTD) has been found to be a result of many different causes including the following: MTD in the presence of an organic pathology (i.e. organic type), MTD stemming from vocal use (i.e. functional type), and MTD as a result of personality and/or psychological factors (i.e. psychogenic type). Causes
The most common causes of hoarseness is laryngitis (acute 42.1%; chronic 9.7%) and functional dysphonia (30%). Hoarseness can also be caused by laryngeal tumours (benign 10.7 - 31%; malignant 2.2 - 3.0%). Causes that are overall less common include neurogenic conditions (2.8 - 8.0%), psychogenic conditions (2.0 - 2.2%), and aging (2%).A variety of different causes, which result in abnormal vibrations of the vocal folds, can cause dysphonia.
Palatal myoclonus is a rare condition in which there are rhythmic jerky movements or a rapid spasm of the palatal (roof of the mouth) muscles. Chronic clonus is often due to lesions of the central tegmental tract (which connects the red nucleus to the ipsilateral inferior olivary nucleus).When associated with eye movements, it is known as oculopalatal myoclonus. Signs and symptoms
Signs and symptoms of Palatal Myoclonus include:
- A rhythmic clicking sound in the ear due to the opening and closing of the Eustachian tube.- Rhythmic, jerky movements in the face, eyeballs, tongue, jaw, vocal cord or extremities (mostly hands). Diagnosis
Classifications
physiologic, essential, epileptic, and symptomatic

Treatment
Drugs
Drugs used to treat palatal myoclonus include clonazepam, carbamazepine, baclofen, anticholinergics, tetrabenazine, valproic acid, phenytoin, lamotrigine, sumatriptan, and PIR. A rare case of palatal myoclonus that associated with orofacial buccal dystonia has been treated with Botulinum toxin A (Dysport) injection and counseling. Notes
http://www.tchain.com/otoneurology/disorders/central/opm.html
https://www.hindawi.com/journals/criot/2013/231505/
"NINDS Tremor Information Page". National Institute of Neurological Disorders and Stroke. July 20, 2007. Archived from the original on October 6, 2007. Retrieved 2007-10-08. References


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