Fig. 4. Hyperpolarizing cell SE1 (middle trace) with approximately 1 nA of current, which abolishes all spiking activity in cell SE1, eliminates all EPSPs and spiking activity in cell 204 (bottom trace), along with all large motor unit activity in DP(8) (top trace). Upon release of cell SE1 from hyperpolarization, excitatory activity immediately returns in both cell 204 and DP(8). B. Expanded section (indicated by the dashed lines) of A. In both A and B the asterisk (*) indicates the occurrence of a stimulus artifact caused by the injection of a hyperpolarizing current pulse into cell SE1. Vertical scale bar corresponds to both cell SE1 and cell 204. Return to Results