Parkinsonian Speech Variability: Medication-Related Fluctuations across Three Days

A Goberman, L Elmer, E Mackowiak, B Heaton


Individuals with Parkinsonís disease (PD) experience fluctuations in response to their levodopa-based medications.These fluctuations have been found to have a consistent effect on non-speech movements, but effects on speech production are inconsistent.The goal of this study was to examine factors that may cause speech production variability in PD speakers.This study examined speech, motor, fatigue, and anxiety fluctuations in 2 individuals with PD across three days each (9 recordings each).On each day, recordings were completed before medication (OFF State), 1 hour after (ON1 state), and 2 hours after taking medication (ON2 state).Speech measures included Fo, FoSD, Articulation Rate, and Percent Pause taken from prolonged vowels, a paragraph reading, and a monologue.Results indicated that motor status changes were consistent across days (most severe motor impairment consistently in OFF state).Fatigue appeared to be unaffected by speech recordings, and corresponded directly with motor impairment.Day-to-day variability in speech production was most pronounced in the OFF state, and speech measures were least variable when medication was working (ON states).Discussion focuses on implications of current findings for future PD research.