Hi Marc,

Those 5 regressors are highly correlated. You can see it
visually when using just "1dplot -sepscl my.xmat.1D" (if
we suppose your X-matrix is called my.xmat.1D). You can
get the correlation values with 1d_tool.py, too:

1d_tool.py -infile my.xmat.1D -show_cormat_warnings


That requires the latest AFNI binaries, from last night.

----

In particuar, regressors 17 and 18 (your first 2 of interest)
are practially just negatives of each other.

On top of that, regressor 21 (the last one) is on practically
the entire time. These will certainly start to match the
baseline when they are put together.

----

It's a little difficult to ponder without knowing your design
in detail. But the curves look problematic, when taken
together.

Also, for a block design, I do not think it is good to have
multiple stimulations at the same time. If a brain location
has already plateaued/saturated due to one stimulus, I do not
expect much difference to be seen from another stimulus that
is supposed to have a response plateau at the same time.

- rick

P.S. You do not need to contact Bob separately. It is just
good to tell the person that you are communicating with, so
they know the data has been uploaded.