Supervised spike sorting feasibility of noisy single-electrode extracellular recordings: Systematic study of human C-nociceptors recorded via microneurography

PLoS ONE, vol. 20, pp. e0329537

Abstract

Sorting spikes from noisy single-channel in-vivo extracellular recordings is challenging, particularly due to the lack of ground truth data. Microneurography, an electrophysiological technique for studying peripheral sensory systems, employs experimental protocols that time-lock a subset of spikes. Stable propagation speed of nerve signals enables reliable sorting of these spikes. Leveraging this property, we established ground truth labels for data collected in two European laboratories and designed a proof-of-concept open-source pipeline to process data across diverse hardware and software systems. Using the labels derived from the time-locked spikes, we employed a supervised approach instead of the unsupervised methods typically used in spike sorting. We evaluated multiple low-dimensional representations of spikes and found that raw signal features outperformed more complex approaches, which are effective in brain recordings. However, the choice of the optimal features remained dataset-specific, influenced by the similarity of average spike shapes and the number of fibers contributing to the signal. Based on our findings, we recommend tailoring lightweight algorithms to individual recordings and assessing the "sortability feasibility" based on achieved accuracy and the research question before proceeding with sorting of non-time-locked spikes in future projects.

Authors 8

1. Alina Troglio corresponding Aachen Institute of Neurophysiology Research group Neuroscience Interdisciplinary Center for Clinical Research (IZKF) Faculty of Medicine

   Universitätsklinikum Aachen · Universitätsklinikum Würzburg · RWTH Aachen University

   Affiliation as printed

   Universitatsklinikum Aachen;

   Department of Anesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, Center for Interdisciplinary Pain Medicine, Würzburg, Germany

   Institute of Neurophysiology, RWTH Aachen University Hospital, Aachen, Germany

   Research Group Neuroscience, Interdisciplinary Centre for Clinical Research (IZKF), Faculty of Medicine, RWTH Aachen University, Aachen, Germany

2. Peter Konradi Aachen Institute of Medical Informatics Faculty of Medicine

   RWTH Aachen University

   Affiliation as printed

   Rheinisch-Westfalische Technische Hochschule Aachen Medizinische Fakultat;

   Institute of Medical Informatics, Faculty of Medicine, RWTH Aachen University, Aachen, Germany

3. Andrea Fiebig Aachen Institute of Neurophysiology Research group Neuroscience Interdisciplinary Center for Clinical Research (IZKF) Faculty of Medicine

   Universitätsklinikum Aachen · RWTH Aachen University

   Affiliation as printed

   Universitatsklinikum Aachen;

   Institute of Neurophysiology, RWTH Aachen University Hospital, Aachen, Germany

   Research Group Neuroscience, Interdisciplinary Centre for Clinical Research (IZKF), Faculty of Medicine, RWTH Aachen University, Aachen, Germany

4. Ariadna Pérez Garriga Aachen Institute of Medical Informatics Faculty of Medicine

   RWTH Aachen University

   Affiliation as printed

   Rheinisch-Westfalische Technische Hochschule Aachen Medizinische Fakultat;

   Institute of Medical Informatics, Faculty of Medicine, RWTH Aachen University, Aachen, Germany

5. Rainer Röhrig Aachen Institute of Medical Informatics Faculty of Medicine

   RWTH Aachen University

   Affiliation as printed

   Rheinisch-Westfalische Technische Hochschule Aachen Medizinische Fakultat;

   Institute of Medical Informatics, Faculty of Medicine, RWTH Aachen University, Aachen, Germany

6. James Philip Dunham

   University of Bristol

   Affiliation as printed

   University of Bristol School of Physiology Pharmacology and Neuroscience;

   Anaesthesia, Pain, and Critical Care Sciences, School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, United Kingdom

7. Ekaterina Kutafina Aachen Scientific Center for Neuropathic Pain Research Aachen

   University of Cologne · Universitätsklinikum Aachen · University Hospital Cologne · RWTH Aachen University

   Affiliation as printed

   Universitat zu Koln Medizinische Fakultat

   Institute for Biomedical Informatics, Faculty of Medicine, University Hospital Cologne, University of Cologne, Cologne, Germany

   Scientific Center for Neuropathic Pain Research Aachen, SCNAACHEN, Uniklinik RWTH Aachen University, Aachen, Germany

8. Barbara Namer Aachen Research group Neuroscience Interdisciplinary Center for Clinical Research (IZKF) Faculty of Medicine

   Universitätsklinikum Würzburg · RWTH Aachen University

   Affiliation as printed

   Rheinisch-Westfalische Technische Hochschule Aachen Medizinische Fakultat;

   Department of Anesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, Center for Interdisciplinary Pain Medicine, Würzburg, Germany

   Research Group Neuroscience, Interdisciplinary Centre for Clinical Research (IZKF), Faculty of Medicine, RWTH Aachen University, Aachen, Germany