Hi Ben,
> Is this whole-brain mask based on the individual's EPI or is this based off
> the epi template?
No, it is based on your imaging data which is simply thresholded to
define the volume of interest to be examined during statistical
analyses. There is a setting in spm_defaults.m that defines the
threshold to be used (in spm8, it's defaults.mask.thresh). If you do
different analyses you will find that the mask is different, too.
It is a good idea to check this mask in any case, as sometimes one
wonders why a region is not activated and, upon examining the mask.img,
realizes it was not even analyzed; this may happen if one image has a
limited FOV, as regions with NaN in one image are not investigated in
either image (I think :) An alternative is to specify the mask
explicitly in the stats options.
Hope this helps,
Marko
--
=====================================================================
Marko Wilke (Dr.med./M.D.)
[log in to unmask]
Universitäts-Kinderklinik University Children's Hospital
Abt. III (Neuropädiatrie) Dept. III (Pediatric neurology)
Hoppe-Seyler-Str. 1, D - 72076 Tübingen
Tel.: (+49) 07071 29-83416 Fax: (+49) 07071 29-5473
=====================================================================
|