Fig. 4: Context-dependent modulation of song contents.

a Experimental scheme of devaluation training. “Reward” day and “Excess-reward” day were repeated each for 3 days. b The shift of repetition, t(4) = 3.18, n = 5 birds. c Experiment scheme. Reward day and “No-reward” day were repeated for 3 days. d The shift of repetition number, t(4) = 7.25, n = 5 birds. e The shift of repetition across days of “Reward” days (left, red) and “No-reward” days (right, blue) within the 3-day period. f Scheme of training and test sessions. Repetition training was conducted with a colored frame on the monitor. g, h The shift of repetition number in the test sessions when the rule was changed for a 1-day cycle (g) and 1-h cycle (h), t(4) = −4.55 and −4.21, n = 5 birds. i Shift of the ratio of repetition number in the “Reward color” condition against “No-reward color” condition in the 1-h cycle. The ratio of early sessions (10:00–15:00) and late (17:00–22:00) sessions within the days are shown. Throughout the panels, the box plot shows the median and first and third quantiles with the mean shown as a circle, P values, two-sided paired t-test; t(4) = 2.16, 1.71, −0.347 from day 1 to day 3; n = 5 birds.