Fig. 8.

Photostimulation reliably induces regular spike trains at low but not high frequencies. A, top: spike rasters of four cells stimulated with sequences of light pulses at 5, 10, 20, and 40 Hz (repetition rate 0.2 Hz). Bottom: magnified view of responses to first light pulses. Shading highlights stimulation period. B–E: success and doublet rate, spike onset latency, and spike time jitter for each of the four cells (columns) shown in A, respectively. Doublets were not scored for cell 9. Cells 8–9 were stimulated with 7-ms light pulses, and cells 10–11 with 5-ms light pulses. Conventions are as shown in earlier figures.