Dear Wouter,

That's an interesting question, and yes, you are exactly right you could do that by manually adding a series of first-level covariates (one per FIR time-delay) for every task condition, and then simply including these covariates in the 'confounds' list during the Denoising step.

If you have an event-related design, and are already entering your design information into CONN, one trick to have CONN create those first-level covariates automatically for you would be the following:

1) in Setup.Conditions select your task conditions and select the 'temporal decomposition (sliding window)' option. Then enter in the 'sliding-window onsets' field the values "0:TR:18" (without the quotes and changing TR for your actual TR value, in seconds), and enter in the 'sliding-window length' field the value 0. This will create a series of new conditions modeling the corresponding FIR components (up to 18s). 

2) in Setup.Basic and change there the 'continuous' acquisition type to 'sparse'

3) in Setup.Conditions select all your new FIR-component conditions (named something like 'task x Time1', 'task x Time2', etc.) and click on 'condition tools' and select there the option that reads 'move selected conditions to covariates list'. This will delete your newly created conditions and create instead a series of new first-level covariates modeling the desired FIR-components (without any form of hrf convolution, thanks to step (2) above). 

4) (clean-up) in Setup.Conditions select your original task conditions and simply revert the 'time-frequency decomposition' field to the original 'no decomposition' value, and in Setup.Basic revert the 'acquisition type' field to its original 'continuous' value.


Hope this helps
Alfonso

Originally posted by Wouter De Baene: