Dear SPM gurus,
I was able to find in previous postings explanation of how to claculate the
(mean brain normalized) percent change in a certain voxel (using plot ->
contrast of parameter estimates), and how to obtain the time series of
changes in a volume of interest (using the new spm_regions function). I was
wondering if you could assist me with the following two questions:
1. How can one obtain the percent change estimate for a small V.O.I., i.e. a
single number rather than the full time series? I'm getting too much
variance when looking at the percent change in a single voxel, and I think
that for instance, the mean beta values in a VOI would be a better
representative.
2. Is there a simple way of finding the location of (global and/or local)
maximal signal change, rather than the location where the t statistic is
maximised?
thanks in advance,
Shy
