Fig. 6.

A CMP can be driven by high-frequency stimulation of the CBC. A, C15, C4, and C12 all receive rhythmic input during CBC stimulation (open bar). The faster time-base records to the right show examples of the input to each neuron during the periods indicated by thenumbered arrowheads on the slow record. The briefdownward deflections represent CBC stimulus artifacts.B, In another preparation, stimulation of the CBC again resulted in rhythmic input, this time recorded in C15, C4, and C16/C17. In this case, C15 was hyperpolarized by 11 mV, which prevented any spiking during the middle three cycles of the CMP, showing that spiking in C15 was not necessary for this CMP. Note that this CMP had a similar cycle period to the CMP driven by C15 and that all of the neurons received similar inputs in both programs (compare with Figs. 3, 4).