quote:
Originally posted by tali:
Does anyone know how to do a small volume correction with brain voyager? (this is for when you have an apriori hypothesis about where the activation is and you want to adjust your p).
Thanks, Tali
Hi Tali,
as far as I know..you will have to do it manually. It's a bit tricky in the beginning but it works.
You define the Roi first (e.g. a sphere around amygdala ...voi file). So you know how many voxels are included in the region you are examining. Let's say 1000
Ok..for whole head correction the programm would just divide p(uncorrected) by the number of ALL voxels in your brain (huge..). Thus it is most conservative, while uncorrected is of course least conservative. SVC instead is somewhere in between...
What you do then is not to divide the UNCORRECTED p by the number of all BUT by the number of 1000 voxels (just an example) instead! You calculate the new p (uncorrected), which can be adjusted manually then.
Hope it helped!
Take care,
LARA