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  • Review Article
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Translational opportunities and challenges of invasive electrodes for neural interfaces

Nature Biomedical Engineering volume 7, pages 424–442 (2023)Cite this article

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Abstract

Invasive brain–machine interfaces can restore motor, sensory and cognitive functions. However, their clinical adoption has been hindered by the surgical risk of implantation and by suboptimal long-term reliability. In this Review, we highlight the opportunities and challenges of invasive technology for clinically relevant electrophysiology. Specifically, we discuss the characteristics of neural probes that are most likely to facilitate the clinical translation of invasive neural interfaces, describe the neural signals that can be acquired or produced by intracranial electrodes, the abiotic and biotic factors that contribute to their failure, and emerging neural-interface architectures.

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Fig. 1: Neural signals and traditional probe architectures.
Fig. 2: Electrode–tissue interface and electrode coatings.
Fig. 3: Abiotic failure modes.
Fig. 4: Biotic failure modes.
Fig. 5: Ultrasmall and ultraflexible electrodes.
Fig. 6: Electrode architectures designed for tissue integration.
Fig. 7: High-channel-count recording technologies.

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Acknowledgements

O.C. was supported by a National Science Foundation Graduate Research Fellowship. J.L.E. was supported by a Hertz Fellowship. M.M.M. is a Chan-Zuckerberg Biohub Investigator.

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  1. Konlin Shen

    Present address: Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA

Authors and Affiliations

  1. University of California, Berkeley – University of California, San Francisco Graduate Program in Bioengineering, Berkeley, CA, USA

    Konlin Shen & David K. Piech

  2. Department of Electrical Engineering and Computer Science, University of California, Berkeley, CA, USA

    Oliver Chen, Jordan L. Edmunds & Michel M. Maharbiz

  3. Department of Bioengineering, University of California, Berkeley, CA, USA

    Michel M. Maharbiz

  4. Chan-Zuckerberg Biohub, San Francisco, CA, USA

    Michel M. Maharbiz

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M.M.M. and K.S. supervised the project. K.S., O.C., J.L.E. and D.K.P. performed literature review and wrote the manuscript. K.S. prepared the figures, with contributions from O.C. All authors contributed to the revision of the manuscript.

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M.M.M. is an employee of iota Biosciences, Inc., a fully owned subsidiary of Astellas Pharma., Inc. D.K.P. is bound by a confidentiality agreement to not disclose details of a potential competing interest. K.S., O.C. and J.L.E. declare no competing interests.

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Shen, K., Chen, O., Edmunds, J.L. et al. Translational opportunities and challenges of invasive electrodes for neural interfaces. Nat. Biomed. Eng 7, 424–442 (2023). https://doi.org/10.1038/s41551-023-01021-5

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  • DOI: https://doi.org/10.1038/s41551-023-01021-5

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