Figure 5.

ACC Represents Model-Based Decision Variables

(A) Regression analysis predicting neuronal activity as a function of events in the current trial (top panel) and their interaction with the transition probabilities (trans. probs.) mapping the first-step choice to second-step (sec. step) states (bottom panel) for a subset of sessions with sufficient coverage of both states of the transition probabilities. Predictors plotted in top panels are as in Figure 3E. Predictors plotted in the bottom panel are transition probabilities (which of the two possible states the transition probabilities are in; see Figure 1C), common/rare transition (whether the transition on the current trial was common or rare, i.e., the interaction of the transition on the current trial [e.g., top → right] with the state of the transition probabilities), choice × trans. probs. (the choice in the current trial interacted with the state of the transition probabilities, i.e., the predicted second-step state given the current choice), and sec. step × trans. probs. (the second-step state reached on the current trial interacted with the state of the transition probabilities, i.e., the action which commonly leads to the second-step state reached). Predictors shown in top and bottom panels of (A) were run as a single regression but plotted on separate axes for clarity. The gray bars between choice and outcome indicate the time period that was warped to align trials of different length. Circles indicate where CPD is significantly higher than expected by chance, assessed by permutation test with Benjamini-Hochberg correction for comparison at multiple time points.

(B) Regression analysis predicting neuronal activity as a function of events on the current trial (top panel) and their interaction with the reward probabilities in the second-step states (bottom panel) for a subset of sessions with sufficient coverage of different states of the reward probabilities. Predictors plotted in the bottom panel are reward probabilities (which of the three possible states the transition probabilities are in; see Figure 1C), transition × reward probs. (interaction of the transition in the current trial with the state of the reward probabilities), choice × reward probs. (the choice in the current trial interacted with the state of the reward probabilities), and sec. step × trans. probs. (the second-step state reached in the current trial interacted with the state of the rewarded probabilities, i.e., the expected outcome [rewarded or not]. Predictors shown in top and bottom panels of (B) were run as a single regression but plotted on separate axes for clarity.