The effect of behavioral context on 5-HT response. A, For trials with a |Df| of <20 Hz, the AUC of 5-HT current was significantly smaller in trials in which the fish produced chirps (nfish = 6; chirp trials, ntrials = 14; no-chirp trials, ntrials = 14; pKWT = 0.02). B, Chirping did not affect the 5-HT response to stimuli with large |Df| values (nfish = 4; chirp trials, ntrials = 41; no-chirp trials, ntrials = 34; pKWT = 0.72). C, KWT p value estimates for comparisons made between the AUC calculated over 5-s-long, nonoverlapping windows between chirp and no-chirp trials. Red, |Df| <20 Hz; blue, |Df| ≥20 Hz. The difference in AUC between chirp and no-chirp trials for |Df| values <20 Hz gains significance within the second 5 s window after stimulus onset. There was no significant difference between chirp and no-chirp trials for |Df values ≥20 Hz. The horizontal dashed line corresponds to pKWT = 0.05.