POC stimulation does not trigger a change in AB activity. A, Suction electrode recordings from the AB axon in the son illustrate that the activity of AB appears similar pre- and post-POC stimulation. Before POC stimulation, there was no gastric mill rhythm (no LG activity in lgn), but there was a pyloric rhythm (rhythmic AB bursting). Note that POC stimulation triggered a gastric mill rhythm, represented by the LG neuron bursting (lgn), but did not evidently change AB firing rate or burst duration. B, Quantification of the average number of action potentials per pyloric-timed AB burst (left) and AB intraburst firing frequency (right) indicate no difference between pre- and post-POC stimulation. After POC stimulation, AB activity was quantified separately during the protraction (Post-Pro) and retraction (Post-Ret) phases of the gastric mill rhythm. Error bars indicate SEM. NS, p > 0.05.