Hi FSL experts,
I had several questions about creating the PSYCH term (i.e., a contrast; https://fsl.fmrib.ox.ac.uk/fsl/fslwiki/PPIFAQ). If I have four related stimuli conditions in a block-design, is it possible to make the following contrasts within the same model: cond1-control, cond2-control, cond3-control? Would it be appropriate to convolve this contrast? If so, how would you determine the duration of the convolution (note: block duration for cond1, cond2, and cond3 are the same but the block duration for control is much shorter).
In a different PPI model, is it possible to model the PSYCH term as a linear contrast? If so, would I need to also include an average and quadratic contrast to make the model complete? And similarly, would the convolution be appropriate here as well?
Thank you!,
Ekarin
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