Dear SPM-ers,
I am using a higher-order shim during fMRI scanning to maximize SNR in the medial temporal lobe. I am wondering if using the Realign and Unwarp step might be problematic in this case (it's the Unwarp aspect I'm particularly concerned about), since by using the shim I am creating inhomogeneity on purpose (higher field strength in the MTL) to get more signal from this region. Would correcting out a very high intense region that I've purposely applied result in over-correction? Any advice is greatly appreciated.
Thank you!
Meera Paleja
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