The contrasts are going to be created automatically. These will be: fund - stands for "fundamental" - this is the F-test of the sine and cosine components, probably what you want fund-sin -- t-test of the sine component (this may also be useful) fund-cos -- t-test of the cosine component (think of this like the derivative when you assume a shape) harm -- F test on the harmonics (probably not too useful)
It is going to assume that the first condition is ON. This does not matter for the F-tests above, but will affect the sign of the sine component.
doug
Chindhuri Selvadurai wrote:
Hello,
We are trying to set up the analysis for a periodic design alternating between 30s rest and 30s active condition. Because abblocked doesn't require a paradigm file, how do we specify which condition comes first (rest or active)? We understand that abblocked expects that the conditions will be alternating.
Also, how do we set up the -a and -c weighting conditions if we are using abblocked, since it doesn't have a paradigm file? How do we specify the arguments for this command? Should we instead be using the -ncond and -wcond commands?
Best,
Chindhuri Selvadurai
Psychiatric Neuroimaging, Manoach Lab Martinos Center for Biomedical Imaging, MGH Phone: (617)726-0307
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