Acoustic evaluation of short-term effects of repetitive transcranial magnetic stimulation on motor aspects of speech in Parkinson’s disease
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Hypokinetic dysarthria in Parkinson’s disease (PD) can be characterized by monotony of pitch and loudness, reduced stress, variable rate, imprecise consonants, and a breathy and harsh voice. Using acoustic analysis, we studied the effects of high-frequency repetitive transcranial magnetic stimulation (rTMS) applied over the primary orofacial sensorimotor area (SM1) and the left dorsolateral prefrontal cortex (DLPFC) on motor aspects of voiced speech in PD. Twelve non-depressed and non-demented men with PD (mean age 64.58 ± 8.04 years, mean PD duration 10.75 ± 7.48 years) and 21 healthy age-matched men (a control group, mean age 64 ± 8.55 years) participated in the speech study. The PD patients underwent two sessions of 10 Hz rTMS over the dominant hemisphere with 2,250 stimuli/day in a random order: (1) over the SM1; (2) over the left DLPFC in the “on” motor state. Speech examination comprised the perceptual rating of global speech performance and an acoustic analysis based upon a standardized speech task. The Mann–Whitney U test was used to compare acoustic speech variables between controls and PD patients. The Wilcoxon test was used to compare data prior to and after each stimulation in the PD group. rTMS applied over the left SM1 was associated with a significant increase in harmonic-to-noise ratio and net speech rate in the sentence tasks. With respect to the vowel task results, increased median values and range of Teager-Kaiser energy operator, increased vowel space area, and significant jitter decrease were observed after the left SM1 stimulation. rTMS over the left DLPFC did not induce any significant effects. The positive results of acoustic analysis were not reflected in a subjective rating of speech performance quality as assessed by a speech therapist. Our pilot results indicate that one session of rTMS applied over the SM1 may lead to measurable improvement in voice quality and intensity and an increase in speech rate and tongue movements. Nevertheless, these changes were not accompanied by changes in a perceptual evaluation of speech performance by a speech therapist. Future placebo-controlled studies in larger patient cohorts should verify if rTMS would be clinically useful for treating hypokinetic dysarthria in PD.
KeywordsHypokinetic dysarthria Parkinson’s disease rTMS Acoustic evaluation
This work was supported by project NT13499 (Speech, its impairment and cognitive performance in Parkinson’s disease), project SIX (CZ.1.05/2.1.00/03.0072), project GACR 102/12/1104, and project “CEITEC, Central European Institute of Technology”: (CZ.1.05/1.1.00/02.0068) from the European Regional Development Fund.
Conflict of interest
The authors declare that they have no conflict of interest.
- Barrett J, Della-Maggiore V, Chouinard PA, Paus T (2004) Mechanisms of action underlying the effect of repetitive transcranial magnetic stimulation on mood: behavioral and brain imaging studies. Neuropharmacology 29:1172–1189Google Scholar
- Beck AT, Steer RA, Brown GK (1996) Manual for the beck depression inventory-2. Psychological Corporation, San Antonio, TXGoogle Scholar
- Boersma P, Weenink D (2012) Praat: doing phonetics by computer (Version 5.3.23) http://www.praat.org/. Accessed 27 August 2012
- Boggio PS, Fregni F, Bermpohl F, Mansur CG, Rosa M, Rumi DO, Barbosa ER, Odebrecht Rosa M, Pascual-Leone A, Rigonatti SP, Marcolin MA, Araujo Silva MT (2005) Effect of repetitive TMS and fluoxetine on cognitive function in patients with Parkinson’s disease and concurrent depression. Mov Disord 20(9):1178–1184PubMedCrossRefGoogle Scholar
- Chaudhuri KR, Martinez-Martin P, Brown RG, Sethi K, Stocchi F, Odin P, Ondo W, Abe K, MacPhee G, MacMahon D, Barone P, Rabey M, Forbes A, Breen K, Tluk S, Naidu Y, Olanow W, Williams AJ, Thomas S, Rye D, Tsuboi Y, Hand A, Schapira AHV (2007) The metric properties of a novel non-motor symptoms scale for Parkinson’s disease: results from an International Pilot Study. Mov Disord 22(13):1901–1911PubMedCrossRefGoogle Scholar
- Daniels N, Oates J, Phyland D, Feiglin A, Hughes A (1996) Vocal characteristics and response to levodopa in Parkinson’s disease. Mov Disord 11(Suppl. 1):117Google Scholar
- Fahn S, Elton RL, UPDRS Development Committee (1987) Unified Parkinson’s disease rating scale. In: Fahn S, Marsden CD, Calne DB, Goldstein M (eds) Recent developments in Parkinson’s disease. Macmillan, Florham Park, pp 153–163Google Scholar
- Jankovic J, McDermott M, Carter J, Gauthier S, Goetz C, Goelbe L, Huber S, Koller W, Olanov C, Shoulson I, Stern M, Tanner C, W. Weiner W, and Parkinson Study Group (1990) Variable expression of Parkinson’s disease: a baseline analysis of the DAT ATOP cohort. Neurology 40:1529–1534CrossRefGoogle Scholar
- Larson KK, Ramig LO, Scherer RC (1994) Acoustic and glottographic voice analysis during drug-related fluctuations in Parkinson’s disease. J Med Speech Lang Pathol 2:227–239Google Scholar
- Lee JY, Kim JW, Lee WY, Kim JM, Ahn TB, Kim HJ, Cho J, Jeon BS (2010) Daily dose of dopaminergic medications in Parkinson disease: clinical correlates and a posteriori equation. Neurology Asia 15(2):137–143Google Scholar
- Michaelis D, Gramss T, Strube HW (1997) Glottal-to-noise excitation ratio—a new measure for describing pathological voices. Acta Acustica 83:700–706Google Scholar
- Murdoch BE (1998) Dysarthria: a physiological approach to assessment and treatment. Nelson Thornes, CheltenhamGoogle Scholar
- Roubickova J, Hedanek J, Stranik A (2011) Dysarthric profile. Galen, PrahaGoogle Scholar