Hi all,
In my study I have 14 subjects who underwent two imaging sessions in
which the same condition was compared to baseline using the contrasts
[1,0] for session 1 and [0,1] for session 2, for each individual
first-level analysis. I subsequently did a 2nd-level group analysis for
each session and observed less activation in the second session. How
can I best determine if the difference between sessions is statistically
significant? Is is correct to do this either with a paired t-test or a
one-way (within-subjects) ANOVA with two conditions (ie. the [1,0] and
[0,1] contrast images)? And then I would enter either a T- or
F-contrast of [1,-1] to identify areas where session1 activation was
greater than session 2 activation? Which is more appropriate, a
T-contrast or an F-contrast?
Thanks for your help,
Daron
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Daron Owen
Graduate Student
Medical Biophysics
University of Western Ontario
London, Ontario, CANADA
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