Clinical Trial: Cerebellum and Cortical Plasticity: the Case of Dystonia

Study Status: Completed
Recruit Status: Unknown status
Study Type: Interventional

Official Title: Cerebellum and Cortical Plasticity: the Case of Dystonia

Brief Summary:

Purpose

- Objective : Sensorimotor adaptation allows the modification of the motor command taking into account the errors detected during execution of prior movements. It involves a large cortico-subcortical network. Isolated lesions of this network do not systematically alter sensorimotor adaptation except for cerebellar lesions. The cerebellum is thus a key structure for sensorimotor adaptation. However, the link between cerebellar and the cortical plasticity underlying sensorimotor adaptation remain unknown. Alteration of sensorimotor adaptation is associated with dystonia but it is unclear whether it is a cause or consequence of dystonia. It has been hypothesized that the abnormal plasticity observed in dystonia could account for the associated alteration of sensorimotor adaptation.

Classically, basal ganglia dysfunction is considered to be crucial for dystonia pathogenesis. However, recent studies suggest that the involvement of the cerebellum may also be important in this setting. In primary dystonia, imaging studies showed abnormal cerebellar activation during sensorimotor adaptation tasks and neurophysiological studies demonstrated a decrease of cerebellar output.

The aim of this study is to investigate the role of the cerebellum in the cortical plasticity underlying sensorimotor adaptation both in healthy subjects (normal plasticity) and in dystonic patients (abnormal plasticity).

- Methods: Paired associative stimulation PAS consists in repetitive pairing of a peripheral nerve and a cortical stimulation. This kind of stimulation has been designed to induce artificial plasticity that can be easily measured. This PAS induced sensorimotor plasticity is exacerbated and has lost its topographical specificity in dystonic

Detailed Summary:
Sponsor: Institut National de la Santé Et de la Recherche Médicale, France

Current Primary Outcome: Comparison of MEP0/MEP10 and MEP0/MEP30 values obtained after sham, cRTBS or iTBS of the cerebellum. [ Time Frame: 6 weeks ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

• Variation of the appropriate dystonic clinical score (depending on the type of dystonia) after each rTMS session (cTBS, iTBS, sham). [ Time Frame: 6 weeks ]
  The effect of rTMS induced modulation of the cerebellar output on dystonic symptoms will be assessed by the variation of the appropriate dystonic clinical score (depending on the type of dystonia) after each rTMS session (cTBS, iTBS, sham).
• Measurement of number of errors, mean time to reach the target after each rTMS session (cTBS, iTBS, sham). [ Time Frame: 6 weeks ]
  The effect of rTMS induced modulation of the cerebellar output on the performance at the sensorimotor adaptation task will be assessed by measurement of number of errors, mean time to reach the target after each rTMS session (cTBS, iTBS, sham).
• Measurement of the variation of the motor threshold, intracortical inhibition and intracortical facilitation after each rTMS session (cTBS, iTBS, sham). [ Time Frame: 6 weeks ]
  The effect of rTMS induced modulation of the cerebellar output on other parameter reflecting cortical excitability will be assessed by measurement of the variation of the motor threshold, intracortical inhibition and intracortical facilitation after each rTMS session (cTBS, iTBS, sham).

Original Secondary Outcome: Same as current

Information By: Institut National de la Santé Et de la Recherche Médicale, France

Dates:
Date Received: January 5, 2011
Date Started: January 2011
Date Completion: January 2014
Last Updated: January 27, 2012
Last Verified: January 2012