Fig. 4: Thermoplasmonic neurite ablation and desynchronization between disconnected networks.

a Phase-contrast and anti-beta-III-tubulin staining images of ablated neurites. Red, black, and white arrowheads indicate neurite transection, beading, and fragmentation, respectively. Scale bar: 20 μm. The images shown are representative of two independent experiments. b Phase-contrast images of neurite outgrowth after agarose ablation (14 DIV, 18 DIV) and before and after neurite ablation (23 DIV). The NIR-focused area is shown by a white circle. Scale bar: 30 μm. The images shown are representative of three independent experiments. c Raster plots of electrodes in N₁ and N₂ before and after ablation. Pink shaded regions indicate synchronized activities within a 100 ms window. Red arrowheads indicate synchronized activities across N₁ and N₂. d Array-wide rate histograms (100 ms bins) before, during (pink shade), and after stimulation. e Representative correlation matrices before and after stimulation. f Mean correlation coefficients of three MEAs before (i) and after (ii) neurite ablation. Each graph indicates an individual MEA. The red graph shows the values of the MEA in Fig. 4e.