Effect of bilateral stimulation of the subthalamic nucleus on parkinsonianvoice

The purpose of this study was to assess several acoustic features of the vo ices of 26 parkinsonian patients under two conditions. with and without bil ateral chronic stimulation of the subthalamic nucleus (STN) to estimate the effectiveness of this procedure on parkinsonian speech. When compared to u nstimulated patients, stimulated patients showed longer duration of sustain ed vowels, shorter duration of sentences, nonsense words, and pauses, more variable fundamental frequency (f0) in sentences. and more stable f0 during sustained vowels. Relative intensity was unchanged in both conditions. Fur ther acoustic analyses are warranted to clarify the role of STN stimulation on parkinsonian speech. (C) 2001 Academic Press.