Fig. 7. Action potential propagation in LPd7 through LCeN3 and LCeN6. Single units corresponding to LPd7 were identified in LCeN3 and LCeN6 (see text for details). Simultaneous intracellular (LPd7) and extracellular (LCeN3 or LCeN6) recordings indicate that spontaneous action potentials were detected in the cell soma before they were detected in the cerebral nerves. Thus, action potentials propagate from the cell body toward the periphery of the animal.