Figure 2.

Coordination of firing activities of the cells with abdominal movements and heartbeat reversals, obtained from a 3-day-old female. (A) Firing of the cells. (B) Numbers of spikes counted every 20 s. (C) Movement of the abdomen. (D) Electrocardiogram. High-frequency pulses are evident during a forward beating period and low-frequency pulses are evident during a backward beating period. The first forward beating pulse is indicated by an arrowhead. Time 0 = 14 h:21 min:43 s. [Calibration bars = 0.2 mV (A and D) and 2 mm (C).]