Fig. 4: Group-level analysis of activation differences and correlations with behavioral measures (Experiment 2).

A Activation differences across the three groups, with significant clusters in the dACC, bilateral MTG, right MFG, and PCC. B Parameter estimates extracted from the identified brain regions. The PD-FOG group showed significantly higher activation levels compared to the PD-nFOG and HC groups in all regions. C Brain-behavior correlation analysis: Spearman’s correlation analysis across all participants showed significant correlations between activation in the identified regions (dACC, MTG, MFG, and PCC) and reaction time costs. D Correlation analysis within the PD-FOG group: Significant correlations between activation intensity in dACC, left MTG, and PCC with severity of FOG (FOG-Q item 3 score). All box plots show the minimum, maximum, median, 1st quartile, and 3rd quartile. p-values (asterisks) indicate the following significance levels: *p < 0.05, **p < 0.01, ***p < 0.001.