Can you attach screenshots of the normalized images after using both methods? To see where the problem may lie?
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From: SPM (Statistical Parametric Mapping) [[log in to unmask]] On Behalf Of Ce Mo [[log in to unmask]]
Sent: Friday, July 29, 2011 10:58 AM
To: [log in to unmask]
Subject: [SPM] [Urgent] Confusing results of two ways of normalisation
Dear SPMers,
I ran into a very confusing problem when I tried to analyze my data in 2 ways of normalisation.
The first method is probably a more commonly used one, Normalisation Estimate&Write, which directly transforms the EPI data to the standard MNI space. However, I do not get very ideal results using this method. The extension of voxels survived FWE of the same cluster is too small, (only 2 or 3 voxels in one cluster). And I was hoping to get clusters of bigger size. Therefore, I tried to use an indirect way of normalisation.
First I performed corregistration, using high resolution T1 weighted image(structural image) as source image and mean EPI image generated in realignment as reference image. Then I performed segmentation. And finally I performed normalisation: write. The underlying idea is to first map the EPI data to the structural image, then transform it into MNI space. And the reason for this is that T1 weighted image contains more information, which I hope would lead to better results.
However, the results are even more terrifying!! I got none activation using the 2nd method!!! Would you please help me with my problem? I am actually under a deadline... The batch using the 2nd method I used is attached in the mail.
Thank you all in advance. Any suggestions will be greatly appreciated!!
Ce
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