Hi Alfonso,

I'm working on a CONN project (v22.v2407) where I only have functional scans available — no anatomical (structural) scans. I understand that CONN can be run without structural images if the preprocessing pipeline is adjusted accordingly.

Here's what I did so far:

• In the Preprocessing pipeline, I removed all steps involving structural data (e.g., segmentation, normalization using structural).


• The Structural tab in SETUP is currently left blank for all subjects.

However, during denoising or setup, I get this error:

Index exceeds the number of array elements (0).

Error in conn (line 6901)

CONN_h.menus.m_preproc.Xs=conn_fileutils('spm_get_data',CONN_h.menus.m_preproc.XS(1).pinv(CONN_h.menus.m_preproc.XS(1).mat)*xyz);

Do you or anyone know why I might be getting this error and how I can avoid it?

Interestingly, it lets me run denoising and 1st-level without an issue, but I am not sure if ignoring it is a good idea.

I really appreciate any guidance you can provide here!

Best,

Asena