different results Alff and fAlff

Dear Experts,


I ran an ALFF and fALFF analysis on a dataset with 3 different groups. Now I noticed that my the ALFF analysis yielded very different results than the fALFF analysis, i.e. fALFF shows a very strong difference between two of the groups, while ALFF shows no difference at all. 

Should I be worried about this difference? 

If this is normal, how can I explain and interpret this difference?

Thank you for your help.

Kind regards,


These are two different measures, should be different.