Hello all,
I'm looking for some input in a somewhat odd finding. We have fMRI data for 30 subjects undergoing an experimental paradigm. Although we find significant activation at the group level (FWE). In a set of a priori ROIs that were additionally significant
at the group level, only 13 of the 30 subjects displayed consistent activation (p<0.05 uncorrected, within a 9mm sphere of the group peak) across sessions.
We also observed that the spatial SNR in the subjects that displayed consistent activation was significant lower than the subjects that did not display consistent activation. This finding is obviously not in the direction we would have expected (although
we didn't expect there to be any sort of systematic SNR differences as nothing related to the acquisition changes during data collection). Further, summed maximum rotation and translation parameters did not differ between groups. Are there any other factors
that may be salient in these findings or this odd SNR relationship?
Thanks,
Drew
