Dear SPM
I am thinking of using temporal derivatives in my model and avoiding slice timing because our TR is quite long (4 sec). Our paradigm consists of periodic alternate epoch blocks of 20 secs Active vs Rest. Rest is implicitly modelled in the design matrix. So Active takes up the first column and its temporal derivatives the second column. Realignment parameters take up the next 6.
How do I assess the results (e.g. Active greater than than rest) if I want to perform a t-contrasts? Do I type "1 " or "1 1" to include the temporal derivatives?
Ahmed Toosy
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