Voice disorders caused by neurological diseases

Objective. To review voice disorders in neurological diseases, with special emphasis to acoustic analysis. Development In the first part of this article we describe data regarding neural control of voice, physiology of phonation, and examination of the patient with voice disturbances, including the use of voice laboratory, acoustic analysis fundamentals, phonetometric measures and aerodynamic measures. In the second part, we review the voice disturbances associated to neurological diseases, emphasizing into movement disorders (specially Parkinson's disease, essential tremor, and spasmodic dysphonia). Conclusions. A number of neurological diseases causing alterations of corticospinal pathway, cerebellum, basal ganglia and upper andlor lower motoneurons can induce voice disturbances. Voice examination using ear, nose & throat examination, endoscopy and videorecording of laryngeal movements, acoustic analysis, elecroglottography, laryngeal electromyography, and aerodynamic measures, could be useful in the clinical examination of some neurological diseases.