Brain research bulletin
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Brain research bulletin · Jul 2008
Subthalamic local field potential oscillations during ongoing deep brain stimulation in Parkinson's disease.
How deep brain stimulation (DBS) acts and how the brain responds to it remains unclear. To investigate the mechanisms involved, we analyzed changes in local field potentials from the subthalamic area (STN-LFPs) recorded through the deep brain macroelectrode during monopolar DBS of the subthalamic nucleus area (STN-DBS) in a group of eight patients (16 nuclei) with idiopathic Parkinson's disease. Monopolar STN-DBS was delivered through contact 1 and differential LFP recordings were acquired between contacts 0 and 2. ⋯ The low-frequency power increase in STN-LFPs during ongoing STN-DBS could reflect changes induced at basal ganglia network level similar to those elicited by levodopa. In addition, the correlation between the heart beat and the low-frequency oscillations suggests that part of the low-frequency power increase during STN-DBS arises from polarization phenomena around the stimulating electrode. Local polarization might in turn also help to normalize STN hyperactivity in Parkinson's disease.
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Brain research bulletin · Jul 2008
Clinical TrialRecovery of motor disability and spasticity in post-stroke after repetitive transcranial magnetic stimulation (rTMS).
Lately it has been indicated that the stimulation of both sides of the motor cortices with different frequencies of rTMS can improve the behaviour of a paretic arm. We studied the effect of rTMS in severe cases of post-stroke after nearly 10 years. They had wide hemispheric lesion and their paresis had not changed for more than 5 years. ⋯ In both groups C (contralateral hemisphere to the paretic arm) and D (ipsilaterally evoked movement in the paretic arm), the spasticity decreased during the first week, but the movement of the paretic arm improved only in group C. It seems that spasticity can be modified by the stimulation either the affected or the unaffected hemisphere, but the induction of movement can be achieved only by the stimulation of an intact motor pathway and its surrounding area (groups B and C). The improvement in paretic extremities can be achieved with rTMS even after years of stroke when the traditional rehabilitation has failed.