Model comparison between a null model (one set of model-based and model-free regressors for both stimulation conditions) and more complex models that allow for an effect of tDCS on model-based control, model-free control, or both, which shows the null model is significantly more plausible than any of the models that allow for an effect of tDCS on behavioral control.

The second column refers to the number of regressors in the hierarchical regression at the individual subject level (cf. Table 1 and 3). BIC: Bayesian Information Criterion; AIC: Akaike’s Information Criterion.