Dear Dr. McLaren and gPPI forum users,

In my experiment the first 4 runs of each subject are "pre" treatment and runs 5-8 are "post" ("Sess" in the SPM file).
I would like to run a contrast for the same condition but pre vs post treatment.
How do I incorporate this in the code?
Am I overlooking or missing any necessary fields for this type of analysis?
I initially thought to rename the tasks in the last 4 runs to include the word "post" and treat them as "different" tasks,
but this was not possible since tasks must exist in all runs.
Please see following segment of code.

Thank you kindly!
Batiah


P.Estimate=1;
P.contrast=0;
P.extract='eig';
P.Tasks={'1' 'treated_correct' 'treated_incorrect' 'untreated_correct' 'untreated_incorrect' 'baseline_correct' 'baseline_incorrect'};

P.Weights=[];
P.method='cond'; 
P.analysis='psy';
P.CompContrasts=1
P.Weighted=0;
P.subject = curr_sub;
P.Contrasts(1).left={'treated_correct'};
P.Contrasts(1).right={'treated_correct'};
P.Contrasts(1).STAT = 'T';
P.Contrasts(1).name='treated_correct_post_minus_pre';
P.Contrasts(1).MinEvents= 8;

Set the '1' to '0' in P.Tasks and use different names for the 1st four and last four runs.

This should allow you to look at the pre-post difference.

Thank you kindly!