Dear SPM developers,
We know from theory that in order to perform a correct smoothness
estimation during precoloring, voxels outside the brain must be
excluded from the analysis.
How is this accomplished in SPM8?
a) Is it accomplished through masking (e.g with tissue probability maps)?
If so, exactly what kind of mask is used and where in the source code
can one set it?
b) Is it accomplished by using an appropriate prespecified minimum
fMRI intensity value parameter?
If so where in the source code can one change it?
(This might be necessary when using non-standard scanners and/or
non-standard scanning sequences or in cases of excessive signal loss
or abnormal brain functioning.)
c) Is it accomplished by use of an algorithm that determines the
boundaries between brain and non-brain space in some other way?
If so, where is that algorithm described?
Thank you in advance for your most valuable answers.
with best regards,
Nu
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