Diagnostic value of articulation neuromotor instability for neurodegenerative disease detection and rating

Neurodegenerative diseases leave an imprint on both phonation and articulation stability. Hypotonia (muscle stiffness), vocal fold unbalance (bi-laterality) and tremor (altered neuromotor feedback) some ways in which the degeneration manifests. Articulatory instability has been less studied, compared to reduced vowel space and vowel centralization. Another relevant aspect is the dynamic behavior of formant transitions in dyadochokinetic exercises, to assess hypokinetic dysarthria in Parkinson?s Disease (PD). The objective of the study is to compare articulation in PD patients against a normative population from kinematic features estimated on formants using Information Theory to quantify their divergence with respect to normative subjects.