Neurons in the VCN respond to trigeminal stimulation with single- or multipeaked excitatory discharges. (A to F): PSTHs of single unit responses to trigeminal ganglion stimulation (50μA), arrows indicate onset of trigeminal ganglion stimulation at 0.025ms. One, two or more peaks of excitation are seen, lasting for up to 80 ms. Some neurons show chopped discharges at the beginning (A, B, F) or for the entire duration of their response (F). (Adapted with permission from Shore at al., 2003)