Dear SPM experts,
I am new to SPM and trying to coregister fmri images (rest images, 200 volumes) to T1 images and then perform normalization to the MNI space.
Coregistration has been performed with FSL and normalization with SPM and both of them work very well.
But after performing normalization with SPM, i tried to visualize the timecourse of mean intensity of 3 different brain regions. We noticed the presence of several spikes at regular intervals, not present before, not in the original database and not even after FSL normalization.
I can t explain their presence, if they are caused from some artifact, and how to remove them.
Any help or explanation would be greatly appreciated!
Best,
Leonardo
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