AFNI Message Board

Dear AFNI users-

We are very pleased to announce that the new AFNI Message Board framework is up! Please join us at:

https://discuss.afni.nimh.nih.gov

Existing user accounts have been migrated, so returning users can login by requesting a password reset. New users can create accounts, as well, through a standard account creation process. Please note that these setup emails might initially go to spam folders (esp. for NIH users!), so please check those locations in the beginning.

The current Message Board discussion threads have been migrated to the new framework. The current Message Board will remain visible, but read-only, for a little while.

Sincerely, AFNI HQ

History of AFNI updates  

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December 03, 2015 09:46PM
Hi Janina,

For example, note that applying bandpassing between
frequencies 0.01 and 0.1 on a 200 TR time series with
TR = 2s would cost approximately 120 degrees of
freedom. It would then be like starting with only 80
(before censoring, motion, polort, or anything else).

Compare 80 with 3 DoF for the 3 principle components.
That is relatively free. The single mean CSF would
be just one DoF.

Keep in mind, 1 regressor = 1 Dof.


Censoring depends strongly on the type of subjects
that one has. I think you mentioned having higher
motion subjects. If that is the case, you almost
certainly need to use a higher censor limit than 0.3,
or too many subjects would be lost.

If you already have motion files for many subjects,
consider Example 18 from "1d_tool.py -help". That
shows how you could evaluate the effects of various
censor levels (e.g. 0.3, 0.5, 0.75, 1).

Sure using 25% censoring as a cutoff for dropping
subjects seems fine.


Regarding use of WMe along with WMeLocal, I agree
with you. That addition to the example was really
showing the sorts of options one has. Though some
people have used it (also part of why I included
it in the example). In any case, that regressor
is probably not going to have a big effect either
way.

- rick
Subject Author Posted

afni_proc.py combine ANATICOR with CSF-regression without Freesurfer-segmentation?

janina_aletheia December 01, 2015 11:51AM

Re: afni_proc.py combine ANATICOR with CSF-regression without Freesurfer-segmentation?

rick reynolds December 01, 2015 09:30PM

Re: afni_proc.py combine ANATICOR with CSF-regression without Freesurfer-segmentation?

janina_aletheia December 02, 2015 03:40AM

Re: afni_proc.py combine ANATICOR with CSF-regression without Freesurfer-segmentation?

janina_aletheia December 03, 2015 04:48AM

Re: afni_proc.py combine ANATICOR with CSF-regression without Freesurfer-segmentation?

rick reynolds December 03, 2015 09:46PM

Re: afni_proc.py combine ANATICOR with CSF-regression without Freesurfer-segmentation?

janina_aletheia December 04, 2015 08:27AM

Re: afni_proc.py combine ANATICOR with CSF-regression without Freesurfer-segmentation?

rick reynolds December 08, 2015 09:08PM

Re: afni_proc.py combine ANATICOR with CSF-regression without Freesurfer-segmentation?

janina_aletheia December 09, 2015 09:40AM