Parametric analysis of pilot voice signals in Parkinson?s disease diagnostics

Parkinson's disease (PD) is a neurodegenerative disease of the central nervous system (CNS) characterized by the progressive loss of dopaminergic neurons in the substantia nigra. The article describes an analysis of pilot voice signal analysis in Parkinson's disease diagnostics. Frequency domain signal analysis was mainly used to assess the state of a patient's voice apparatus in order to support PD diagnostics. The recordings covered uttering the ?a? sound at least twice with extended phonation. The research utilized real recordings acquired in the Department of Neurology at the Medical University of Warsaw, Poland. Spectral speech signal coefficients may be determined based on different defined frequency scales. The authors used four frequency scales: linear, Mel, Bark and ERB . Spectral descriptors have been defined for each scales which are widely used in machine and deep learning applications, and perceptual analysis. The usefulness of extracted features was assessed taking various methods into account. The discriminatory ability of individual coefficients was evaluated using the Fisher coefficient and LDA technique.. The results of numerical experiments have shown different efficiencies of the proposed descriptors using different frequencies scales.