Metal microdrive and head cap system for silicon probe recovery in freely moving rodent

  1. Mihály Vöröslakos
  2. Peter C Petersen
  3. Balázs Vöröslakos
  4. György Buzsáki  Is a corresponding author
  1. New York University, United States
  2. University of Copenhagen, Denmark
  3. Budapest University of Technology and Economics, Hungary


High-yield electrophysiological extracellular recording in freely moving rodents provides a unique window into the temporal dynamics of neural circuits. Recording from unrestrained animals is critical to investigate brain activity during natural behaviors. The use and implantation of high-channel-count silicon probes represent the largest cost and experimental complexity associated with such recordings making a recoverable and reusable system desirable. To address this, we have designed and tested a novel 3D printed head-gear system for freely moving mice and rats. The system consists of a recoverable microdrive printed in stainless steel and a plastic head cap system, allowing researchers to reuse the silicon probes with ease, decreasing the effective cost, and the experimental effort and complexity. The cap designs are modular and provide structural protection and electrical shielding to the implanted hardware and electronics. We provide detailed procedural instructions allowing researchers to adapt and flexibly modify the head-gear system.

Data availability

All documentations for parts and device fabrication are included in the manuscript and supporting files, including video recordings. The same information is made public via GitHub ( Data from example electrophysiological recordings are available here (

Article and author information

Author details

  1. Mihály Vöröslakos

    Neuroscience Institute, Langone Medical Center, New York University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Peter C Petersen

    Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
    Competing interests
    The authors declare that no competing interests exist.
  3. Balázs Vöröslakos

    Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Budapest, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  4. György Buzsáki

    Neuroscience Institute, Langone Medical Center, Department of Neurology, New York University, New York, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3100-4800


National Institutes of Health (U19 NS107616)

  • György Buzsáki

National Institutes of Health (U19 NS104590)

  • György Buzsáki

National Institutes of Health (R01 MH122391)

  • György Buzsáki


  • Peter C Petersen

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.


Animal experimentation: All experiments were approved by the Institutional Animal Care and Use Committee at New York University Medical Center (protocol number: IA15-01466).

Reviewing Editor

  1. Laura L Colgin, University of Texas at Austin, United States

Publication history

  1. Received: December 16, 2020
  2. Accepted: May 18, 2021
  3. Accepted Manuscript published: May 19, 2021 (version 1)
  4. Version of Record published: June 4, 2021 (version 2)


© 2021, Vöröslakos et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.


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  1. Mihály Vöröslakos
  2. Peter C Petersen
  3. Balázs Vöröslakos
  4. György Buzsáki
Metal microdrive and head cap system for silicon probe recovery in freely moving rodent
eLife 10:e65859.

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