Materials and technologies for soft implantable neuroprostheses

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Implantable neuroprostheses are engineered systems designed to restore or substitute function for individuals with neurological deficits or disabilities. These systems involve at least one uni- or bidirectional interface between a living neural tissue and a synthetic structure, through which information in the form of electrons, ions or photons flows. Despite a few notable exceptions, the clinical dissemination of implantable neuroprostheses remains limited, because many implants display inconsistent long-term stability and performance, and are ultimately rejected by the body. Intensive research is currently being conducted to untangle the complex interplay of failure mechanisms. In this Review, we emphasize the importance of minimizing the physical and mechanical mismatch between neural tissues and implantable interfaces. We explore possible materials solutions to design and manufacture neurointegrated prostheses, and outline their immense therapeutic potential.

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Figure 1: Structure and anatomy of the nervous system.
Figure 2: Mechanical mismatch between the nervous tissues and man-made implantable electrodes.
Figure 3: Compliant and multimodal neural interfaces for the brain.
Figure 4: Compliant and multimodal interfaces for the spinal cord and the peripheral nerves.
Figure 5: Mechanosensitivity and foreign body reaction in the central nervous system.
Figure 6: Functions with compliant neural interfaces.


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Financial support was provided by the Bertarelli Foundation (SPL), Starting Grants from the European Research Council (ERC 259419 ESKIN (SPL), ERC 261247, Walk Again (GC)), the European Community's Seventh Framework Program (CP-IP 258654, NeuWALK (GC)) and the Alexander-von-Humboldt Foundation (Alexander-von-Humboldt Professorship (JG)). The authors thank A. Goriely, K. Franze, P. Janmey, K. Van Vliet, J. Fawcett, R. Franklin, M. Reimer and J. Bloch for useful discussions.

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Correspondence to Stéphanie P. Lacour.

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