Fig. 4
In vivo photostimulation and electrophysiological recording validation. a (Left) Micrograph of probe shank with selected electrodes (1–10) and emitters (A–D) labeled. (Right) Voltage traces from five selected electrodes showing evoked spikes during a 30-ms optical pulse from Emitter D at 28% optical power (emission power ≈1.3 μW). The displayed voltage traces were processed with common average referencing, bandpass filtering (300–6000 Hz), and photostimulation artifact removal. b Waveforms of two sorted single units (Units 1 and 2) from electrodes 6 and 9, respectively. c Autocorrelograms of the two sorted units. d Spiking raster plot of Unit 1 during the 30 ms photostimulation period over 150 pulses with Emitter C at 100% optical power (≈4.9 μW). e Mean firing rate of the two sorted units with photostimulation from different emitters at 100% optical power. Mean baseline firing rates are averaged over 10 s before each stimulus. Error bars represent the standard error of the mean (SEM). f Power dependence of mean firing rates of Units 1 and 2 (averaged over 150 optical pulses from Emitters C and D, respectively)
