Hi,

This isn't an error. It's simply a warning.

The warning is generated because the code is trying to generate contrasts for the temporal (1st) and dispersion (2nd) derivatives. If your design matrix does not have these, it triggers the warning message that you are missing conditions.

If you notice, there is a valid contrast, followed by 2 invalid contrasts --> task, 1st derivative, 2nd derivative contrasts that are attempted to be generated. One could probably write the code better such that it doesn't trigger warnings when the derivatives are missing.

The contrast currently only takes in the task names.

Hope this helps.

-Donald