Figure 3. Estimation and updating of the volatility-driven flexible LR of control demand (N=21).

(a) Searchlights in the AI and adjacent IFG track the model estimates of volatility/LR (in red, P<0.05 corrected, one sample t-test). (b) The flexible control model, highlighting in red the information processing mechanisms related to the updating of LR. (c) Visualization of searchlights encoding LR (red, P<0.05 corrected) and searchlights showing an interaction between predicted conflict level and congruency, or control prediction error (green, P<0.05 corrected, one sample t-test); overlap between these independently defined effects is shown in yellow. (d) Probabilistic distribution of t-values measuring the group-level univariate effect of prediction error of congruency (in grey) and the underlying null t-distribution (in red). The t-values were calculated from searchlights in the LR-encoding cluster shown in (a). The red vertical dotted line denotes the threshold for statistical significance (P<0.05). (e) Group mean activation levels (±s.e.m.) in the left AI/IFG ROI showing significant encoding of the volatility-driven flexible LR. The trial-by-trial ROI-mean fMRI activation (in t-values, in accordance with the univariate and multivariate analyses) were binned for each individual into 20 quantiles, which are plotted as a function of 20 quantiles of the LR (left) and estimation uncertainty (right). (f) Trial-wise estimation uncertainty of a representative example subject, plotted as a function of its corresponding LR. Each trial is represented by a translucent grey disk. Although the correlation coefficient between these two model estimates is significant (r=0.32, P<0.0001), the r² statistic indicates that only 10% of variance is shared between them (for group statistics, see Supplementary Tables 5 and 6).