Figure 4.

Brain-behavior correlation of expectation-induced bias. We observed a significant positive across-subjects correlation between the behavioral criterion shift induced by the prediction cue and the neural activity increase for predictive trials in left DLPFC (Spearman's ρ = 0.50, p = 0.01) and left IPS (Spearman's ρ = 0.61, p = .002). Only trends were found in right DLPFC and right IPS. Conversely, this correlation was negative in left and right MT+, with the effect being significant in right MT+ (Spearman's ρ = −0.38, p = 0.04). The activity increase was computed from the contrast predictive (valid and invalid) > non-predictive (neutral) trials. Criterion shift is a measure of the degree to which subjects adjusted their decision bias (for details, see Materials and Methods). We used Spearman's rank correlation, a nonparametric test that is insensitive to extreme values in the variables. All significant correlations remain significant if Pearson's product-moment correlation was used.