Fig. 6: Neural recording and 2D mapping using optogenetics.

a, b Images of the optogenetic modulation setup with the transparent µECoG array and opaque µECoG array on the ChR2 transgenic mouse brain. The distance between the laser fiber and the electrode array is 1 mm, and optogenetic modulated was performed at 7.32 mW/mm² of laser power density. c, d 2D electrophysiological mapping of optogenetic stimulation from the 16-channel transparent µECoG array and 16-channel opaque µECoG array, showing the exact arrangement of the arrays and scale information. The color maps display voltage changes (ΔVoltage) calculated the differences between before and after 15 ms of 473 nm laser irradiation, with a potential range of (−100–800 μV). The 473 nm pulsed laser was modulated with 50 cycles of on/off (15 ms/400 ms). e Optically evoked neural signals from the ChR2 transgenic mouse at various laser power densities (2.35, 4.07, 7.32 mW/mm²) for both the transparent µECoG array and the opaque µECoG array. f Neural signals from the EGFP injection region (control) under the same 473 nm laser irradiation.