FIGURE 4.

Results of group‐level DCM analyses. (a) Posterior probability of the modulation of B‐parameters in each family. Note that families are not mutually exclusive and therefore the sum of their probabilities may exceed 1. (b) Parameter estimates after Bayesian model reduction (top) and averaging (bottom), corresponding to the modulation of connection strengths by sound deviance (MMN), melodic predictability, musical expertise, and the predictability‐by‐expertise interaction. In model averaging, parameter values are weighted by the posterior probability of the models in the hypotheses space. In contrast, in exploratory model reduction, the evidence for parametric effects is obtained from an exhaustive search across all possible model configurations, in which effects with little evidence are pruned away (i.e., set to 0). Error bars represent 95% credible intervals. (c) Posterior probability of the modulation of each parameter after Bayesian model reduction