Novelty is not surprise: Human exploratory and adaptive behavior in sequential decision-making
Fig 10
ERP variations explained by trial-by-trial and participant-by-participant multivariate linear regression analysis.
Surprise⊥ (magenta), Novelty⊥ (dark blue), NEP⊥ (light blue), R+ (brown) and R− (red) were used as explanatory variables, and the ERP amplitude at each time point was considered as the response variable. A. Encoding power (adjusted R-squared values) averaged over 10 participants (dashed lines show the standard error of the mean) at each time point. Shaded areas and horizontal lines indicate four time intervals (W1, …, W4) of significant encoding power (FDR controlled by 0.1, one-sample t-test, only for the time-points after the baseline). The 3rd time interval has been split into two time windows of equal length for the analysis in C. B. Values of the regression coefficients (averaged over participants) for Surprise⊥, Novelty⊥, NEP⊥, R+, and R− as a function of time. Errors are not shown to simplify the illustration. C. In each of the 5 time windows, the regression coefficients plotted in B have been averaged over time. Error bars show the standard error of the mean (across participants). Asterisks show significantly non-zero values (FDR controlled by 0.1 for each time window, one-sample t-test). The Novelty⊥ coefficients in the 1st and the last time windows (dot) have p-values of 0.03 and 0.04, respectively, which are not significant after FDR correction. In the second time window, Surprise⊥, Novelty⊥, NEP⊥, and R+ have significantly positive coefficients.