Thalamus & Related Systems

Table of Contents - 2001 - Volume 1, Issue 03  


Effect of deep brain stimulation on amplitude and frequency characteristics of rest tremor in Parkinson’s disease

Anne Beuter a1a2a3c1, Michèle S. Titcombe a1a2, François Richer a1, Christian Gross a3 and Dominique Guehl a3
a1 Cognitive Neuroscience Centre (DS-5749), University of Quebec at Montreal, P.O. Box 8888, Station Centre Ville, Montréal Que., Canada H3C 3P8
a2 Physiology Department, Centre for Nonlinear Dynamics in Physiology and Medicine, McGill University, 3655 rue Drummond, Montréal, Que., Canada H3G 1Y6
a3 Service d’Explorations Fonctionnelles du Système Nerveux, CHU de Bordeaux, Hôpital du Levêque, 33600 Pessac, France

Article author query
beuter a   [Google Scholar] 
titcombe ms   [Google Scholar] 
richer f   [Google Scholar] 
gross c   [Google Scholar] 
guehl d   [Google Scholar] 
 

Abstract

The effect of chronic high frequency deep brain stimulation (DBS) on rest tremor was investigated in subjects with Parkinson’s disease (PD). Eight PD subjects with high amplitude tremor (Group 1) and eight PD subjects with low amplitude tremor (Group 2, used as a reference group) were examined by a clinical neurologist and tested with a velocity laser to quantify time and frequency domain characteristics of tremor. Possible rebound effects in rest tremor when DBS was stopped for 60 min were also explored. Participants received DBS of the internal globus pallidus (GPi) (n = 7), the subthalamic nucleus (STN) (n = 6) or the ventrointermediate nucleus of the thalamus (Vim) (n = 3). Tremor was recorded with a velocity laser under two conditions of DBS (on-off) and two conditions of medication (L-Dopa on-off). Correlations between clinical and experimental results for tremor amplitude was 0.70 with no medication and no stimulation. In Group 1, DBS decreased tremor amplitude but also increased spectral concentration and median frequency significantly. Under medication, the changes in tremor with and without stimulation were not statistically significant (Group 1). When stimulation was stopped for 60 min, a rebound in tremor amplitude was observed and median frequency remained stable in Group 1. None of the comparisons examined produced significant effects in Group 2. Taken together, these results suggest that beyond its effect on tremor amplitude DBS acted also on tremor frequency and did not modify tremor characteristics in subjects with low amplitude tremor.

(Published Online April 12 2006)
(Accepted October 2 2001)


Key Words: High frequency chronic stimulation; Time and frequency domain analysis.

Correspondence:
c1 Corresponding author. Address as of January 2002: Faculté des Sciences du Sport et de l’Education Physique, Université Wontpelier I, Montpelier, France. E-mail address: a.beuter@staps.univ-montpl.fr (A. Beuter).