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

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ziad
July 09, 2009 04:05PM
Running 3dvolreg twice won't help.

You can subtract the reference volume from each volume in the time series and see how much left over signal you have before and after registration. However even though the difference volumes are related to the registration cost functional, they are not a quantitative estimate of the error. You can also look at the rmsold and rmsnew parameters that 3dvolreg writes out. But those parameters are not of much use for deciding whether an alignment is acceptable or not.

Did your subjects move suddenly by several mm or over a long duration? If the movement is over a long duration, then that is OK.

cheers.
ziad
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Subject Author Posted

evaluating motion correction

Christy Wilson July 09, 2009 02:04PM

Re: evaluating motion correction

ziad July 09, 2009 04:05PM

Re: evaluating motion correction

Christy Wilson July 13, 2009 10:29AM

Re: evaluating motion correction

rick reynolds July 13, 2009 11:13AM

Re: evaluating motion correction

Christy Wilson July 13, 2009 11:41AM

Re: evaluating motion correction

rick reynolds July 09, 2009 04:36PM