Hi Ekarin,Please see below:On 12 March 2018 at 13:58, Ekarin Pongpipat <[log in to unmask]> wrote: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?Yes, create these 3 EVs with the differences, and include a 4th EV that is cond1+cond2+cond3+control.Would it be appropriate to convolve this contrast?Yes, it is appropriate to do the convolutions on these EVs (not contrasts) before or after the subtractions, and also multiply by the physiological measurement.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).I don't understand this question.
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?I don't understand this question either, sorry.All the best,Anderson
Thank you!,
Ekarin