3dNetCorr and voxels skipped because were constant in time

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1

Hi you all,

I’m using 3dNetCorr to extract the times series (from task and from resting state) between 2 ROIs . I just found out that by adding -ts_wb_corr it also provides whole brain connectivity between each of those ROIs and the rest of the brain , which is super cool .

My question is: it returns this warning: “XX voxels skipped because were constant in time” . I read on one of the thread that this might be ok and probably due to the use of mask/ROI. Is that the case or is there anything wrong in my analysis ?

The outcomes look correct though

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Hi, Lysianne-

Yes, indeed, it is something that might not be unexpected or a problem. It just that the program wants to make sure that the user is aware and verifies that.

You can use this option to output the mask that the program uses/checks with:


-output_mask_nonnull
                     :internally, this program checks for where there are
                      nonnull time series, because we don't like those, in
                      general.  With this flag, the user can output the
                      determined mask of non-null time series.

… and make sure that these null time series don’t appear in bad/unwanted places.

–pt

3

Gotcha , thanks Paul!