Acoustic analysis of intonation in parkinson's disease

The aim of this study was to explore the prosodic characteristics of speakers with Parkinson’s disease (PD) in the marking of intonations. Twenty-four German PD speakers with either mild or moderate degree of dysarthria were compared with twelve non-dysarthric control speakers on the production of imperatives, questions and statements. Acoustic analyses of fundamental frequency (average F0, F0 range and F0 envelop), intensity (average intensity, intensity range and intensity envelop) and speech rate (number of syllable per second) were conducted to investigate the effect of PD on intonation marking. The results showed that the dysarthric and non-dysarthric speakers differed significantly in all F0 measures, with higher average F0 and reduced F0 variability noted for the PD speakers. Although the PD speakers were more monotonous in prosody, they showed similar intonation contrasts between intonations as in non-dysarthric speakers.