The time course of the return of upper limb bradykinesia after cessation of subthalamic stimulation in Parkinson's disease

Received 22 March 2006; received in revised form 27 November 2006; accepted 10 December 2006.

Abstract

To investigate the time span within which bradykinesia re-occurs, we registered movement parameters immediately after the termination of deep brain stimulation of the subthalamic nucleus (STN) in nine Parkinson patients with chronically implanted bilateral STN electrodes. Two repetitive movements were investigated: finger-tapping and forearm pronation–supination. When stimulation was switched off, the amplitude and velocity of the investigated movements significantly declined, but the frequency did not. The time course of this decline was modeled by an exponential function that yielded time constants between 15 and 30s. The effect of stimulation had completely disappeared within 1min. These results suggest that it is necessary to wait at least for 1min after the end of stimulation before performing further assessments.

Keywords: Parkinson's disease, Subthalamic stimulation, Bradykinesia

a Department of Neurology, Ludwig-Maximilians University, Munich, Germany

b Department of Biomechanics, Semmelweis University, Budapest, Hungary

c 2nd Department of Neurology, Comenius University, Bratislava, Slovakia

d Department of Neurosurgery, Ludwig-Maximilians University, Munich, Germany

e Clinical Neuropsychology Research Group, Hospital München-Bogenhausen, Munich, Germany

Corresponding author. Tel.: +498970953673; fax: +498970953677.

1 Both authors contributed equally to this paper.

PII: S1353-8020(06)00289-6

doi:10.1016/j.parkreldis.2006.12.003

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