Figure 2

Conditioning with various delays of the US. (a–f) Averaged PSTHs of the licking responses with delays of − 1 s (a, n = 5 mice), − 0.5 s (b, n = 5 mice), + 0 s (c, n = 5 mice), + 0.5 s (d, n = 7 mice), + 1 s (e, n = 11 mice), or + 2 s (f, n = 7 mice) during trials 161–200. The plot in (d) is the same as that at the bottom of Fig. 1f. Red shades indicate the period of CS presentation. (g) Peak lick scores plotted against time. Each symbol represents the delay in the US relative to the CS. (h) Time windows for US presentation leading to conditioning. The averaged lick scores in the baseline session (white circle) and CS-only trials included during conditioning trials 161–200 (black circle) were plotted against delays between the CS and US. Wilcoxon signed-rank test. *P < 0.05, **P < 0.01.