Hi Gang,

For block designs, my understanding is we have to cast out 'rest' blocks and only keep and concatenate 'task' blocks in the time series when running GCA. Do we do the same for SEM? In case we have to do the same for SEM, there will be a lot of discontinuities in the ROIs' time series. I see that the 'model search' mode of 1dSEM can only be run with group data. It seems to me we can only do this with resting state data. Is this right? What if one runs 'model search' with the whole time series that contain both rest and task related signals?

Another question is, when cutting out a 'task' block, should we keep the whole block or should we remove the first 3-4 TRs of hemodynamic lag?

Thanks for your help.
Duong