I am currently trying to investigate the local correlations across 2 modalities (i.e. Tau-PET and cortical thinning). I understand that this sort of questions has been conventionally addressed using the Biological Parametric Mapping (BPM) toolbox in MATLAB. 

Is there a way in Freesurfer to properly address this?

My PET data have already been registered and projected to the surfaces for each individual. 

Thanks a lot. 

Best Wishes,

Elijah

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