Figure 6. Both rewards and air puffs activated striosomal neurons. A, Normalized ΔF/F of a striosomal neuron showing reward-responsive activities. This is ΔF/F in the late stage. Black dots indicate detected Ca2+ events. B, C, Averaged ΔF/F and Ca2+ events of the striosomal neuron illustrated in A. Yellow areas show the US period. D, Amplitudes of US period Ca2+ events of the striosomal neuron illustrated in A were averaged over trials and plotted against reward size. In rewarded trials, Ca2+ events show a positive correlation with reward size (r = 0.42, p = 9.4e-10). On the other hand, there was no significant correlation in reward-omitted trials (r = 0.16, p = 0.096). Error bars and lines indicate SEs and regression lines. E, Scatter plots of t-values for regression coefficients of delivery of reward (Rwd) in each learning stage. Dashed lines indicate levels of significant Rwd slope at p = 0.05. Letter A indicates the example neuron in A. F, Proportions of reward-responsive neurons in each learning stage. Numbers in bars indicate actual counts of reward-responsive neurons; n.s.: p ≥ 0.05, χ2 test. G, MSEs between actually received and decoded reward size at each number of neurons used for analyses; **p < 0.01, paired t test. H, Normalized ΔF/F of a striosomal neuron showing air-puff-responsive activities. This is also ΔF/F in the late stage. Black dots indicate detected Ca2+ events. I, J, Averaged ΔF/F and Ca2+ events of the striosomal neuron illustrated in H; **p < 0.01, n.s.: p ≥ 0.05, two-sample t test. K, Scatter plots of t values for regression coefficients of delivery of air puff (Air) in each learning stage. Dashed lines indicate levels of significant Air slope at p = 0.05. Letter H indicate example neurons in H. L, Proportions of air-puff-responsive neurons in each learning stage. Numbers in bars indicate actual counts of air-puff-responsive neurons. n.s.: p ≥ 0.05. M, MSEs between actually received and decoded air-puff stimuli at each number of neurons used for analyses; **p < 0.01, paired t test.