Deep brain stimulation can suppress pathological synchronisation in parkinsonian patients

TLDR

Deep brain stimulation of the subthalamic nucleus is a highly effective treatment for severe Parkinson’s disease, yet its mechanism is unclear, with one hypothesis that it suppresses local pathologically synchronized oscillatory activity. The authors recorded local field potentials from STN DBS electrodes in 16 Parkinson’s patients (25 sides) during 60‑µs, 130‑Hz stimulation using a specially designed amplifier to analyze the effect of stimulation voltage. They found that increasing stimulation voltage beyond 1.5 V progressively reduced 11–30 Hz LFP peaks, with median power falling to 54 % of baseline at 3.0 V, indicating that clinically effective DBS suppresses pathological oscillations in the vicinity of the electrode.

Abstract

<h3>Background</h3> Although deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a highly effective therapeutic intervention in severe Parkinson9s disease, its mechanism of action remains unclear. One possibility is that DBS suppresses local pathologically synchronised oscillatory activity. <h3>Methods</h3> To explore this, the authors recorded from DBS electrodes implanted in the STN of 16 patients with Parkinson9s disease during simultaneous stimulation (pulse width 60 μs; frequency 130 Hz) of the same target using a specially designed amplifier. The authors analysed data from 25 sides. <h3>Results</h3> The authors found that DBS progressively suppressed peaks in local field potential activity at frequencies between 11 and 30 Hz as voltage was increased beyond a stimulation threshold of 1.5 V. Median peak power had fallen to 54% of baseline values by a stimulation intensity of 3.0 V. <h3>Conclusion</h3> The findings suggest that DBS can suppress pathological 11–30 Hz activity in the vicinity of stimulation in patients with Parkinson9s disease. This suppression occurs at stimulation voltages that are clinically effective.