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bioRxiv · 10.1101/622670

Stimulation-artifact-free, high-spatiotemporal-resolution in vivo optoEphys with μLED optoelectrodes

Kim, K.·Vöröslakos, M.·Seymour, J. P.·Wise, K. D.·Buzsaki, G.·Yoon, E.
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Abstract

The combination of in vivo extracellular recording and genetic-engineering-assisted optical stimulation is a powerful tool for the study of neuronal circuits. Precise analysis of complex neural circuits requires high-density integration of multiple cellular-size light sources and recording electrodes. However, high-density integration inevitably introduces stimulation artifact. We present minimal-stimulation-artifact (miniSTAR) {micro}LED optoelectrodes that enable effective elimination of stimulation artifact. A multi-metal-layer structure with a shielding layer effectively suppresses capacitive coupling of stimulation signals. A heavily-boron-doped silicon substrate silences the photovoltaic effect induced from LED illumination. With transient stimulation pulse shaping, we reduced stimulation artifact on miniSTAR {micro}LED optoelectrodes to below 50 {micro}Vpp, much smaller than a typical spike detection threshold, at optical stimulation of > 50 mW mm-2 irradiance. We demonstrated high-temporal resolution (< 1 ms) opto-electrophysiology without any artifact-induced signal quality degradation during in vivo experiments. MiniSTAR {micro}LED optoelectrodes will facilitate functional mapping of local circuits and discoveries in the brain.

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Kim, K., Vöröslakos, M., Seymour, J. P., Wise, K. D., Buzsaki, G., Yoon, E.. 2019-04-30. Stimulation-artifact-free, high-spatiotemporal-resolution in vivo optoEphys with μLED optoelectrodes. https://doi.org/10.1101/622670

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