There might be a direct functionality for this in CAT12 but you can do
it manually in SPM12:
* Save > all clusters (n-ary): clusters_mask.gii
* m = gifti('clusters_mask.gii');
% compute cluster sizes
20147 113 47 43 ...
% First value is background
* If I'm interested in the mean beta_1 value within the cluster with 113
vertices, I would do:
g = gifti('beta_0001.gii');
spm_summarise should do this for you automatically but this function
hasn't been updated to handle surface data yet, and it seems that the
option to save a mask of the current cluster does not work as expected
hence relying on n-ary here.
On 11/04/17 21:39, Travis Beckwith wrote:
> I've been using the CAT12 toolbox to generate cortical thickness estimates for analyses. Does anyone know of a way to use a custom mask to extract values from the analysis output files? Specifically, I would like to make a mask from a statistically significant cluster and then use that mask as an ROI for extracting the beta values from the beta_000*.gii files to examine how much confounding variables change the beta values. I understand how to do this for a VBM analysis in SPM when the output are nifti files, but I'm having trouble with the gifti files.
Guillaume Flandin, PhD
Wellcome Trust Centre for Neuroimaging
University College London
12 Queen Square
London WC1N 3BG