Construction of Semi-Supervised Spatial Projections To Identify the Source of Beta- and High Frequency Oscillations in Parkinson’s Disease

Authors

Luciano R F Branco
Ashwin Viswanathan
Arjun Tarakad
Nuri F Ince

Publication Date

4-1-2023

Journal

IEEE EMBS Conference on Neural Engineering

DOI

10.1109/ner52421.2023.10123890

PMID

37601420

PMCID

PMC10440159

PubMedCentral® Posted Date

8-20-2023

PubMedCentral® Full Text Version

Author MSS

Published Open-Access

yes

Keywords

Parkinson’s, beta, HFO, biomarker, projection

Abstract

Traditional deep brain stimulation (DBS) treatment for Parkinson's disease (PD) targets the placement of DBS leads into subthalamic nucleus (STN). Extraction of neurobiomarkers from STN local field potential activity can be used for the optimization of DBS. Beta (12-30 Hz) and high frequency oscillations (200-450 Hz, HFO) of STN and their phase-amplitude coupling have been previously correlated with symptom severity in PD. The typical approach is to take bipolar derivations of electrode contacts in order to enhance recordings of local brain activity and suppress noise levels. This approach can often cancel the signals in correlated neighboring contacts and create ambiguity in which monopolar contact to select for the identification of the main source of the oscillatory signal. To improve local specificity and help identify the source of beta and HFO in terms of electrode contact, we propose a semi supervised blind-source separation method. This approach presents a novel perspective to investigate electrophysiology by projecting the recorded channels into a subspace of virtual channels. We show the contribution of each channel to the identified source and correlate the spatial information with imaging and postoperative programming parameters. We anticipate such a source identification strategy can be used in the future to investigate the distribution of beta and HFO on individual contacts of the DBS lead and can improve the interpretation of these signals.