Extended Data Fig. 8: Comparison of dopamine axon GCaMP signal, control fluorescence signal, and licking.
a, GCaMP signals (top; green), tdTomato signals (middle; red), and lick counts (bottom; blue) recorded simultaneously in the first reversal session from airpuff to reward (mean ± sem). b, Percentage of animals that show anticipatory licking during delay periods vs trial number. Regression coefficient 1.3%/trial, F = 33, p = 1.2 × 10−6, F-test. c, Average lick counts during delay periods vs trial number. Regression coefficient 0.11 lick/trial, F = 35, p = 7.8 × 10−7, F-test. d, First lick timings vs trial number. Regression coefficient −2.3 ms/trial, F = 0.19, p = 0.66, F-test. e, Relation between the first lick and GCaMP signals during the delay period in an example animal. Right, comparison between timing of GCaMP peak and timing of the first lick. f, Linear regression coefficients for timing of GCaMP peak, tdTomato peak, lick peak and first lick with trial number (t = 8.9, p = 8.8 × 10−4 for GCaMP peak; t = −0.058, p = 0.96 for tdTomato peak; t = 0.038, p = 0.97 for lick peak; and t = 0.98, p = 0.38 for first lick, two-sided t-test). Red circles, significant (p-value ≤0.05, F-test, no adjustment for multiple comparison). g, Latency of GCaMP response and first lick (GCaMP peak to first lick, 427 ± 241 ms; and GCaMP response onset to first lick, 989 ± 154 ms, mean ± sem). h, Correlation coefficients between timing of GCaMP response peak and lick peak (t = 1.3, p = 0.27, two-sided t-test) and lick onset (first lick, t = 0.53, p = 0.62, two-sided t-test, and second lick, t = 1.6, p = 0.19, two-sided t-test). Red circles, significant (p-value ≤0.05, F-test, no adjustment for multiple comparison). n=5 animals. Center of boxplot showing median, edges are 25th and 75th percentile, and whiskers are most extreme data points. **p<0.01.
