Figure 4. Comparison of different value coding models. A, Three different models for value coding are shown. Under absolute value coding (left), values are represented independent of the context, thus neural activity patterns encoding the same value in reward and punishment contexts (e.g., +0.0€ and −0.0€) are equivalent. With partially-adaptive coding (middle), values are rescaled so that positive outcomes in punishment contexts (e.g., −0.0€) have a higher value than negative ones in reward contexts (e.g., +0.0€). Finally, if the code is fully adaptive (right) neural patterns encoding a positive outcome in different contexts are equivalent, but different from those encoding negative outcomes, which are identical as well. B, Results of the analysis comparing different value coding models. The absolute coding model is the best at predicting neural activity patterns representing factual outcome when partial feedback is provided (left) in all ROIs. Instead, for counterfactual outcome value encoding (right) the fully-adaptive coding model is the one with higher prediction accuracy (see Materials and Methods, Comparing different valuecoding models). For factual outcome encoding when complete feedback is given (middle), the model with higher prediction accuracy is either the fully-adaptive or the partially-adaptive one, depending on the ROI. C, Interaction effect of coding model × type of outcome. The absolute model had higher prediction accuracy for factual outcomes with partial information than both the partially-adaptive and the fully-adaptive models. Instead, the fully-adaptive model had higher prediction accuracy than the absolute model for factual and counterfactual outcomes with complete feedback. pOFC, posterior OFC; FPC, frontopolar cortex; vACC, ventral ACC; dACC, dorsal ACC; MCC, middle cingulate cortex; vSFG, ventral SFG. Error bars represent SEM. ***p < 0.001, **p < 0.01.