Dysprosody in Parkinson's disease: an investigation of intonation patterns.

Acoustic research of intonation in dysprosody has often been restricted to overall measures - such as range and variability of fundamental frequency (F[sub 0]) - without consideration of the interactions between intonation contours and acoustic measurements. The aim of this acoustic study was to investigate three aspects of disordered intonation in hypokinetic dysarthria resulting from Parkinson's disease (PD): adequacy of accent patterns, timing of pitch accents, and the influence of levodopa-medication on peak height in fundamental frequency. Three PD speakers participated in a single-subject design study. Eighteen sentences were recorded at different times after ingestion of levodopa. Intonation contours were categorized and F[sub 0] was measured at lows and highs of the observed contours. Compared to controls, PD speakers showed reduced peak height and placed F[sub 0] peaks more often directly on the accented syllables. Medication caused a decrease of peak height in one of the accents in speaker 1, an increase of peak height in some accent patterns in speaker 2 and no changes in speaker 3. [ABSTRACT FROM AUTHOR]