Dataset Information

Effects of subthalamic nucleus stimulation on motor cortex plasticity in Parkinson disease.

ABSTRACT:

Objective

We hypothesized that subthalamic nucleus (STN) deep brain stimulation (DBS) will improve long-term potentiation (LTP)-like plasticity in motor cortex in Parkinson disease (PD).

Methods

We studied 8 patients with PD treated with STN-DBS and 9 age-matched healthy controls. Patients with PD were studied in 4 sessions in medication (Med) OFF/stimulator (Stim) OFF, Med-OFF/Stim-ON, Med-ON/Stim-OFF, and Med-ON/Stim-ON states in random order. Motor evoked potential amplitude and cortical silent period duration were measured at baseline before paired associated stimulation (PAS) and at 3 different time intervals (T0, T30, T60) up to 60 minutes after PAS in the abductor pollicis brevis and abductor digiti minimi muscles.

Results

Motor evoked potential size significantly increased after PAS in controls (+67.7% of baseline at T30) and in patients in the Med-ON/Stim-ON condition (+55.8% of baseline at T30), but not in patients in the Med-OFF/Stim-OFF (-0.4% of baseline at T30), Med-OFF/Stim-ON (+10.3% of baseline at T30), and Med-ON/Stim-OFF conditions (+17.3% of baseline at T30). Cortical silent period duration increased after PAS in controls but not in patients in all test conditions.

Conclusions

Our findings suggest that STN-DBS together with dopaminergic medications restore LTP-like plasticity in motor cortex in PD. Restoration of cortical plasticity may be one of the mechanisms of how STN-DBS produces clinical benefit.

SUBMITTER: Kim SJ

PROVIDER: S-EPMC4534071 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Publications

Effects of subthalamic nucleus stimulation on motor cortex plasticity in Parkinson disease.

Kim Sang Jin SJ Udupa Kaviraja K Ni Zhen Z Moro Elena E Gunraj Carolyn C Mazzella Filomena F Lozano Andres M AM Hodaie Mojgan M Lang Anthony E AE Chen Robert R

Neurology 20150708 5

<h4>Objective</h4>We hypothesized that subthalamic nucleus (STN) deep brain stimulation (DBS) will improve long-term potentiation (LTP)-like plasticity in motor cortex in Parkinson disease (PD).<h4>Methods</h4>We studied 8 patients with PD treated with STN-DBS and 9 age-matched healthy controls. Patients with PD were studied in 4 sessions in medication (Med) OFF/stimulator (Stim) OFF, Med-OFF/Stim-ON, Med-ON/Stim-OFF, and Med-ON/Stim-ON states in random order. Motor evoked potential amplitude an ...[more]

PMID: 26156511

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Dataset Information

Effects of subthalamic nucleus stimulation on motor cortex plasticity in Parkinson disease.

Objective

Methods

Results

Conclusions

Publications

Effects of subthalamic nucleus stimulation on motor cortex plasticity in Parkinson disease.

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