Hi - I would do a fixed-effects analysis at second level, separate
for each subject, that achieves this contrast.
Then the 3rd level group analysis is a simple mean (all 1s EV).
Cheers.
On 18 May 2007, at 18:23, Vishwadeep Ahluwalia wrote:
> Hi,
> I've 10 subjects ,2 sessions each. 1st session has stimuli A and B
> and 2nd
> session has stimuli C and D. for group analysis how do i specify the
> contrast [(A+B+C)/3]-D in FSL? i'm trying to find areas which have
> decreased
> activation for condition D. any thoughts?
> -vish
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Stephen M. Smith, Professor of Biomedical Engineering
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