Figure 8.

(a) Peri-stimulus time histograms (PSTH) (top), rasterplots (middle) and latency histograms (bottom) of elicited spikes from the same contact (see insets, in orange) when stimulating sequentially through three neighboring optrodes (see insets, in blue). Notice the stronger activation and shorter latency when stimulating through the middle and closest optrode compared to the optrodes one position left and right. (b) Confocal image of the transduced culture (mCherry) with the location of the recorded contact (in yellow) and the three stimulated optrodes (in blue).