(a) Fraction of VP neurons best fit by the Value and Unmodulated models in the random sucrose/maltodextrin/water task. (b) Mean(+/−SEM) activity of neurons best fit by each of the models, plotted according to previous outcome. (c) Coefficients(+/−SE) for outcome history linear regression for each class of neurons (n=38 Value and 216 Unmodulated neurons). (d) Mean(+/−SEM) population activity of simulated and actual Value neurons according to each trial’s Value (V). (e) Mean(+/−SEM) activity of all Value neurons with trials binned by model-derived Value. (f) Distribution of correlations between individual VP neurons’ firing rates at cue onset on each trial and the distance from the port during the previous ITI. * = p = 0.00001 for significant negative shift in mean correlation coefficient (vertical line) compared to 1000 shuffles of data for Value neurons, Wilcoxon signed-rank test, two-sided, as well as p = 0.0000002 for more negative coefficients for Value neurons compared to Unmodulated neurons, Wilcoxon rank-sum test, two-sided. See also Fig. 4c-d.