Hi Nathan,
To start with, the 'true mean' of all voxel values in the mask is computed.
Then the mean for only those voxels with values > 'true mean'/8 is computed.
This is similar to the thresholding used in SPM. It excludes the influence
of non-brain voxels with very low values.
When using a fairly tight mask the two means are virtually the same.
Best
Leighton
> Could you please explain to me the "Mean > Mean/8" in
> the output of Mask toolbox if it is not too much
> trouble. Thank you.
>
> Nathan Klimenko
>
>
>
>
>
> >
> > How can I normalize the count of each voxel to the
> average count of
> > cerebellum? Is it possible to do this with SPM2?
> >
>
> Hi Nathan,
>
> The 'Masks' toolbox will do this for you. You can
> download it from
> http://www.anzsnm.org.au/ftp/idl/Masks.htm. It
> includes a cerebellum
> mask.
>
> Leighton
>
>
> Leighton Barnden PhD
> Medical Scientist
> Nuclear Medicine, The Queen Elizabeth Hospital
> Adelaide, SA 5011,
> Australia
> ph. +61 8 8222 6438
>
>
>
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