Dear list,
For a VBM analysis I am working with data that is already intensity
non-uniformity corrected using the N3 function
(http://www.bic.mni.mcgill.ca/software/N3/). To avoid double bias
correction or an interaction between the two bias corrections of N3
and SPM5 I would like to optimize the setting for bias regularisation
and bias FWHM within SPM5.
Based on the emails in the SPM mailbase and the SPM-manual I
understood that if data has little inhomogeneity the setting for the
bias regularisation would be to allow for only very little
flexibility, i.e. using the 'extremely heavy regularisation' setting
in my case.
However, I find it difficult to understand what to do with the bias
FWHM. Do I choose a broader cutoff (i.e. a cutoff of 150 mm), or 'no
correction' at all in combination with the 'extremely heavy
regularisation'?
Thank you in advance,
Simone Reinders.
http://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind03&L=SPM&P=R93815&I=-3
http://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind05&L=SPM&P=R202337&I=-3
http://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind06&L=SPM&P=R98508&I=-3
http://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind0701&L=SPM&P=R40918&I=-3
the spm-manual (section 5.3.6 and 5.3.7).
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