Hello

I have a NIFTI file that shows how many participants show tuned responses at each location on the cortical surface (Image 1 attached to the message).
This NIFTI file is in Talairach space (TT_N27_SurfVol in AFNI). I have mapped this file on std.141.TT_N27_both.spec in AFNI (Image 2 attached to the message). I want to map the activity from std.141.TT_N27_both.spec on each of my subjects surfaces (std.141). I have created the surface of each subject in FreeSurfer and convert it to AFNI format using @SUMA_Make_Spec_FS. Would you please tell me which command I should use in AFNI to project activity from one surface to another? Is it SurfToSurf? I read about this command that is used to interpolate data from one surface (S2) to another (S1), assuming the surfaces are quite similar in shape but having different meshes (non-isotopic). But here, the two surfaces have a similar mesh (std.141) and different shapes.
After projecting the activity on the subject’s surface, I want to save it as a NIFTI file to use it as an ROI for the analysis. Would you please tell me what the command is for this conversion?
Actually, what I want is a mask (nii file) of yellow and orange activity. But I want the mask in my subject’s native space.