Dear List Users,
I am trying to create a lateralisation index for fMRI activation in verbal
fluency tasks in individual subjects. I am using the VOI button to create a
sphere of 5mm radius around a peak activation. I am then using a script
that I have found posted on this list to calculate all the beta values for
the voxels from which I am calculating a mean. My questions are as follows:
1) Using the voi button I get no option to 'adjust data' - by default it
does not adjust - is there a reason I cannot choose the adjust option and
perhaps more importantly what does this adjust for exactly ?
2) Using the VOI button I note that it only picks up voxels that are
significant at whatever threshold I am using - is this a problem in view of
the fact that when I mirror ny VOI to the other side (which shows less
activation in the language task), it will contain far fewer voxels in a VOI
of the same size. Is there a way around this ?
Thank you.
Mahinda
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