it would be not that easy to extract the gray matter (GM) volume over a cluster. An alternative way which is quite often practiced is to extract the mean GM values inside a cluser using the function "eigenvariate" that is available in the results GUI. Here you can extract the component which explains most of the variance in your cluster and the values for all data sets can be obtained on the Matlab command line by the variable "Y". Thus, call the eigenvariate function, choose cluster as VOI definition and the variable Y will be available on your Matlab coomand line. This will be a good approximation to the mean volume inside a cluster for your purpose.
On Mon, 27 Mar 2017 16:02:41 +0200, Rossella Oliva <[log in to unmask]> wrote:
>I'm using VBM 8. How can I extract a cluster’s gray matter volume in
>mm3 for every subject (to plot the correlations with other cognitive
>Thank you in advance.
>Rossella Oliva, PhD student
>Department of General Psychology
>University of Padua
>*Via Venezia 8 - 35131 Padova, Italy*
>Phone: +39 049 827 6403