Dear SPMers,
I would greatly appreciate your help in understanding how I could analyse a
dataset in SPM5. I have two groups (A,B) that completed three consecutive
runs (1,2,3) of a task, each run generating a single contrast (task stimuli >
control stimuli). I am interested in determining whether there are brain regions
that show either increasing or decreasing activation over time (i.e., across the
three runs). My impression for reading some literature was that a linear trend
analysis would be appropriate, but I am uncertain as to whether this is the
best approach, and if so, how to implement this in SPM5 to look at the main
effect of time within each group, then see if there are Group X Time
interactions (i.e., group differences in regions that show increases over time,
differences in regions that show decreases over time).
Your help is greatly appreciated
Sincerely,
Robert Roth
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