Deryk,
Sorry for ignoring your original question. I don't think it will make a big
difference either way (but make sure you check the performance of
eddy_correct, using FSLView's movie tool whenever you use it, as sometimes
it makes things worse). You could run it both ways on a single subject and
then run dtifit and see if there is any significant difference in the
result.
Glad you found my paper useful. If you are interested in a comparative
perspective on the arcuate fasciculus, we have another paper that will be
coming out in Nature Neuroscience any day now that compares the pathway in
Humans, Chimpanzees, and Macaques.
Peace,
Matt.
-----Original Message-----
From: Deryk Beal [mailto:[log in to unmask]]
Sent: Thursday, March 06, 2008 12:11 PM
To: [log in to unmask]; Matt Glasser
Subject: Re: Eddy current correction before or after resampling?
Hi Matt
Thanks for your reply. I too am concerned about these potential
limitations. I still am going to go beyond the standard FA and ADC
measurements to gain some experience with TBSS and a feel for the pitfalls
such as this as I feel it will benefit my planning of my next DTI
acquisition.
I think I am going to change the order of my processing so that eddy
correction is done before downsampling the data so that the FA maps
generated by FSL are available for comparison to those done with
DTIStudio. I still have not had a response as to the impact of the order
of these steps.
Cheers,
Deryk
PS Keep up the good work you are doing imaging the arcuate fasciculus.
Your most recent paper in Cerebral Cortex will inform the interpretation
of the results of an MEG study I am completing.
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