Dopamine (DA) effects on time delay between LP and PY onset, and LP to PY onset phase difference during normal pyloric network activity. A: Mean effect of DA on LP to PY time delay. B: Mean effect of DA on LP to PY onset phase difference. Neither difference is statistically significant (LP to PY time delay, paired t test, p = 0.10; LP to PY onset phase, paired t test, p = 0.73). C: Time delay between LP and PY onset for each of 21 PY neurons under control (white bars) and DA (black bars) conditions. PY neurons are grouped by their firing in control conditions: silent, firing before LP, and firing after LP. The last group is subdivided by whether DA causes a phase advance or a phase delay.