Paired Deep Brain Stimuli Elicit Short-Term Facilitation in Globus Pallidus Interna and Subthalamic Nucleus

Deep brain stimulation (DBS) elicits oscillatory local field potentials in patients with Parkinson's disease (PD) and other movement disorders. Greater knowledge about the fast dynamics of these neural responses could shed light on circuit pathophysiology and inform novel approaches to neuromodulation therapies.

To compare short-term neuroplasticity in the globus pallidus interna (GPi) and the subthalamic nucleus (STN), the canonical functional targets for PD and dystonia.

During surgery for DBS lead implantation, we delivered pairs of stimuli across various interstimulus intervals and amplitudes and recorded DBS-evoked responses from unused contacts on the lead. After stimulus artifact removal, we contrasted the magnitude and timing of the local responses by paired pulse interval and brain target. Additionally, we compared the amplitudes of the DBS-evoked potentials versus resting local field potentials at the same recording site.

In 14 patients undergoing STN DBS and 9 undergoing GPi DBS, evoked potentials in the STN exhibited greater amplitudes than those in the GPi. However, paired pulse neuroplasticity was larger in the GPi than in the STN. Otherwise, the responses at both sites exhibited similar paired pulse hastening and refractoriness, onset latencies, and frequencies measured by the first two peaks.

Single and paired DBS pulses elicit local oscillations with larger amplitudes in the STN than in the GPi. Otherwise, the responses display similar time dynamics and short-term neuroplasticity. These findings could inform therapeutic innovation with future DBS systems that utilize sensing technologies. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.