Abstract
A prospective study regarding the effect of TRH on the motor speech disorder of three patients with spinocerebellar degeneration (SCD), the first with hereditary cortical cerebellar atrophy, the second and third with sporadic olivo-ponto-cerebellar atrophy, was performed The effect was analyzed by using speech evaluation, such as the auditory impression, the questionnaire of the consciousness for verbal communication, the phonetic evaluation and the acoustic analysis. The results of the analysis and the mechanism of the improvement of the motor speech disorder are discussed. Only the first patient showed a remarkable improvement subjectively. In addition, the improvement of phonation and articulation was demonstrated quantitatively in the evaluation of the first patient. On the other hand, by phonation analysis using VISI-PITCH, it was seen that there were a decrease in the perturbation of the voice pitch and an increase in voice range in all three patients. Therefore, it was concluded that the improvement of phonation plays a major role in the improvement of the motor speech disorder. Such improvement of the phonation seems to have resulted from the improvement of coordination, mainly due to the normalization of the muscle tone of the larynx by TRH administration. Although a remarkable beneficial effect of TRH may be obtained in exceptional patients of SCD, the mechanism of such an effect of TRH should be more extensively studied using the quantitative clinical evaluation of phonation and articulation.