Hi,
> I found some inconsistencies when comparing the volume of a cluster shown in
> SPM and marsbar.
> When I want to investigate a functional cluster determined by a specific
> contrast I chose, I put my cursor on the local maximum of that cluster and
> by clicking on "current cluster" I can see how many voxels this cluster
> contains. E.g. in one case, this cluster contains 52 voxels. When I want to
> make this cluster my ROI, I just write this cluster using marsbar. However,
> when I then look at that written ROI (of the same cluster) using the marsbar
> function "View", it says that the volume of this ROI is 3564 mm.
Well - then - marsbar must think there were more voxels in the ROI
than SPM does. I'm not sure why that is. In the past I have
attributed this to the F-threshold used by SPM:
http://www.nabble.com/discrepancy-of-total-number-of-voxels-of-clusters-between-marsbar-and-SPM-td21732553.html
but, I'm not sure if this is the case for SPM5. Can anyone more up
with SPM5 than me chip in?
Best,
Matthew
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