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Name of database:
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DBSPDTREMOR
Effect of Deep Brain Stimulation on Parkinsonian Tremor

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Name of creator(s) of database:
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Anne Beuter
Michele S. Titcombe
Leon Glass

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Description of database:
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  This database contains recordings of rest tremor velocity in the index
finger of 16 subjects with Parkinson's disease (PD) who receive chronic
high frequency electrical deep brain stimulation (DBS) either uni- or
bi-laterally within one of three targets: the ventro-intermediate
nucleus of the thalamus (Vim) (n=3), the internal Globus pallidus (GPi)
(n=7) or the subthalamic nucleus (STN) (n=8).  All participants were
clinically stable at the time of the recordings, they did not show
cognitive impairment, and did not suffer from a major depressive
disorder.  

 The surgical procedure for high frequency deep brain stimulation
involves implanting an electrode into subcortical structures (Vim, GPi
or STN) for long-term stimulation at frequencies greater than 100 Hz.
The mechanism by which high frequency DBS suppresses tremor and reduces
other symptoms in PD is unknown.

  The raw data were obtained using a low intensity velocity-transducing
laser that was directed at a piece of reflective paper on the subject's
index finger tip, with the output voltage proportional to the velocity of
the finger.  Tremor was recorded for approximately 60 seconds under various
conditions:
(1) two conditions of DBS (on-off) and two conditions of medication
    (L-dopa on-off) 
    [total: 54 recordings of approx 60 seconds each]
(2) every 15 minutes when DBS was stopped for 60 minutes (medication off)
    [total: 46 recordings of approx 60 seconds each]
Please note that not all subjects were tested under all conditions.

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References to any published works that describe or
make use of the database, in the form in which these
works should be cited in any future publications
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Beuter, A., Titcombe, M.S., Richer, F., Gross, C., Guehl, D.,
2001. Effect of deep brain stimulation on amplitude and frequency
characteristics of rest tremor in Parkinson's disease. Thalamus &
Related Systems, Volume 1 (3): 203-211 (published by Elsevier Science).

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Contact information:
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(1) Dr. Anne Beuter
    Faculte des Sciences du Sport et de l'Education Physique
    Universite Montpellier I
    700, avenue du Pic Saint-Loup
    F-34090 Montpellier, France
    a.beuter@staps.univ-montp1.fr
(2) Dr. Michele Titcombe
    Centre for Nonlinear Dynamics in Physiology and Medicine
    McGill University
    3655, promenade Sir William Osler
    Montreal, QC, Canada
    titcombe@cnd.mcgill.ca
(3) Dr. Leon Glass
    Centre for Nonlinear Dynamics in Physiology and Medicine
    McGill University
    3655, promenade Sir William Osler
    Montreal, QC, Canada
    glass@cnd.mcgill.ca