Hi Rick,
Thanks for your reply. All .nii files at this stage are z maps generated from correlation with a ROI, and I am using 3dTcorr1D to correlate these z maps with a behavior measure (e.g. age). The output from 3dTcorr1D is interesting, so I am hoping to correlate each z map with its appropriate value in the behavior measure.
Since posting, someone suggested to me that I use the interesting cluster that shows up after 3dTcorr1D to make a new mask, then extract each subject's fcMRI peak for this cluster+my original seed. (I presume, using 3dmaskave.) Does that sound right?
Thank you for your help!
Ariel
