(b) Model PE posterior probability maps (PPMs) from group-level Bayesian model selection (BMS) within PE cluster mask, warm colour: TD model PE, cool colour: hybrid model PE (shown at exceedance probability P>0.7). (c) Axiomatic analysis of hybrid model PEs in instrumental sessions, ROIs were 8 mm spheres from BMS peaks favouring TD model PEs, in left putamen and VMPFC. (d) Associability uncertainty generated by hybrid model, as parametric modulators at choice time (duration = 0), in instrumental sessions. (e) Comparing pgACC activations across instrumental/Pavlovian paradigms, ROI was 8 mm sphere at [−3, 40, 5], peak from overlaying the pgACC clusters from Experiments 1 and 2.