Low-threshold, high-resolution, chronically stable intracortical microstimulation by ultraflexible electrodes
Roy Lycke1,2, Robin Kim1,2, Pavlo Zolotavin1,2
1Department of Electrical and Computer Engineering; Rice University; Houston; Texas; 77005, United States.
Biorxiv : the Preprint Server for Biology
|March 3, 2023
Summary
Ultraflexible StimNETs offer stable, high-resolution intracortical microstimulation (ICMS) with minimal tissue response. These nanoelectronic threads enable long-term, low-current neuromodulation, reducing risks associated with traditional electrodes.
Area of Science:
- Neuroscience
- Biomedical Engineering
- Materials Science
Background:
- Intracortical microstimulation (ICMS) is crucial for neuroprosthetics and circuit manipulation.
- Chronic electrode implantation often causes adverse tissue responses, limiting neuromodulation efficacy and stability.
- Existing electrodes face challenges in achieving high resolution, efficacy, and long-term stability due to tissue integration issues.
Approach:
- Engineered ultraflexible stim-Nanoelectronic Threads (StimNETs) for enhanced tissue integration.
- Demonstrated low activation threshold, high resolution, and chronic stability of ICMS in awake, behaving mice.
- Utilized in vivo two-photon imaging to assess tissue integration and neuronal activation over time.
Key Points:
- StimNETs achieved stable, focal neuronal activation at low currents (2 μA) with seamless tissue integration.
- Longitudinally stable behavioral responses were observed for over eight months with low charge injection (0.25 nC/phase).
- Histological analysis revealed no neuronal degeneration or glial scarring after chronic ICMS with StimNETs.
Conclusions:
- Tissue-integrated electrodes like StimNETs offer a promising path for robust, long-lasting neuromodulation.
- StimNETs enable spatially-selective neural control with reduced risk of tissue damage and off-target effects.
- This technology advances the potential for safe and effective neural interfaces.
