Pathophysiology of Neuronal Oscillations Within Subthalamo-cortical Loops in Parkinson's Disease

Study Overview
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Brief Summary
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Neuronal activity in circuits between the basal ganglia (BG) and motor cortical areas is abnormally synchronised and rhythmic. The oscillatory activity prevails at 8-30 Hz in untreated Parkinson's Disease (PD) and its amplitude at both subthalamic and cortical levels inversely correlates with motor impairment. Moreover, these different levels in BG-cortical loops are coherent in this frequency band. The 8-30 Hz activity is suppressed by treatment following treatment with dopaminergic drugs and is partially suppressed prior to and during voluntary movements. An unanswered question is how do BG-cortical loops become so prominently engaged in this oscillatory activity? One possible explanation is that the resonance frequencies of the loops fall in the 8-30 Hz band in the untreated state, so that oscillations in this band are transmitted particularly well. This hypothesis was confirmed in a previous series of experiments.The aim is to determine whether the resonance frequency within BG-cortical loops is correlated to the BG-cortical coherence frequency (with 20 subjets during 24 months).

Detailed Description
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Methods: Record STN-cortex LFP coherence pattern and then stimulate STN (at 0, 5, 10, 15, 20, 25, 30 Hz) in newly implanted patients at rest and during simple and complex motor tasks while recording the steady state evoked potential over the cortex using EEG. The resonance frequency will be calculated as previously (Eusebio et al, Brain 2009). Experiments will be carried out both in the OFF medication and ON medication condition.

Official Title
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Pathophysiology of Neuronal Oscillations Within Subthalamo-cortical Loops in Parkinson's Disease

Conditions
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Parkinson's Disease, Pathophysiology of Neuronal Oscillations Within Subthalamo-cortical Loops

Intervention / Treatment
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* Other: subthalamo-cortical loops stimulation in a one-sided and bipolar way
* Other: subthalamo-cortical loops stimulation in a one-sided and bipolar way


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Parkinson's disease idiopathique evolving for more than 5 years Dopa-Sensibility superior to 50 % Electrodes of stimulation implanted in 2 NST at Timone (Pr PERAGUT) Exclusion Criteria: Bad tolerance of the condition OFF Dopa and\or OFF stimulation
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: dopamine<br>ON DOPA:The patient will take his usual treatment with dopamine | Other: subthalamo-cortical loops stimulation in a one-sided and bipolar way<br>* Record STN-cortex LFP coherence pattern and then stimulate STN (at 0, 5, 10, 15, 20, 25, 30 Hz) in newly implanted patients<br>|
| Experimental: without dopa<br>OFF Dopa: The patient will be deprived of his treatment usual dopaminergique for at least 12 hours | Other: subthalamo-cortical loops stimulation in a one-sided and bipolar way<br>* Record STN-cortex LFP coherence pattern and then stimulate STN (at 0, 5, 10, 15, 20, 25, 30 Hz) in newly implanted patients<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the understanding of the mechanisms underlying the propagation of pathological oscillatory activities in PD |  | 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| may provide a basis for different therapeutic strategies |  | 24 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Parkinson, Pathophysiology, neuronal oscillations