Hi Alfonso,

Thank you very much for the useful information, I appreciate that!

I have checked the histogram displays shown in the Preprocessing step and the ROI files, they both look correct. However, for some reasons, we are using smoothed data(5mm FWHM) for the ROI-to-ROI analysis, do you think it will have a big impact on the result?

In order to make sure I understand correctly, may you check if I use the calculator tool correctly? I am not sure about the 2nd case above..

1) to compare the association between performance and FC (predictor) within one group(e.g. HC), but control for age and gender:
Define contrast [1] for only HC in the secondly-level results and import values for new FC measures (e.g. 'conn between ROI01 and ROI02);
Select in the 'between-subject effects' list: HC, age_HC, gender_HC, new FC measure
Enter the between-subjects contrast:[0 0 0 1]
Select in the 'measures' list: performance_HC
Enter the between-measures contrast:[1]

2) to compare between the two groups(HC and AD) the association between performance and FC (predictor), but control for age and gender:
Define contrast [1] for HC and AD separately in the secondly-level results and import values for new FC measures, new_FC_measures_HC and new_FC_measures_AD (e.g. 'conn between ROI01 and ROI02);
Select in the 'between-subject effects' list: HC, AD, age, gender, new_FC_measure_HC, new_FC_measure_AD;
Enter the between-subjects contrast:[0 0 0 0 1 -1]
Select in the 'measures' list: performance_HC, performance_AD
Enter the between-measures contrast:[1 1]

And, could you please clarify what is the colour of ROIs stand for in ROI-to-ROI result explorer, axial display, when selecting multiply ROIs (see attached picture).

Thank you in advance as usual!
Best regards,
Yifei