Dear FSL users,
I have a question about using Featquery on a high-level cope directory in
order to conduct an ROI analysis on fMRI data.
I have an event-related experiment that has been analysed at three levels,
with separate runs from different participants combined at the mid-level.
For the ROI analysis in featquery, I selected particular cope directories
from the top level analysis and then from the output html page selected the
"Mean time series (masked/weighted)" link. This contains as many data points
as I have participants, and I assume that each data point is the mean
parameter estimate for that contrast within my mask for one participant.
So I was wondering whether this assumption is correct, and if so whether it
makes sense to then conduct simple t-tests on these by-participant values. I
was a little concerned that the mean of these values doesn't match the mean
parameter estimate quoted lower down in the feat report, although they are
fairly similar.
The alternative, I guess, would be to go back to the first level analyses
and run featquery on each run of each participant.
Advice on whether my interpretation is correct would be appreciated!
thanks,
Gareth
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