Alice,

> Your reply illustrated how to average the time series over a Region of Interest

No, that's not necessarily true. If you create a mask that includes only one voxel, you would get the time series for that voxel instead of averaging across an ROI of multiple voxels.

> but can 3dDeconvolve generate a 1-D hemodynamic response function?

That depends on how you modeled the hemodynamic response function. If you used a shape-fixed function such as BLOCK or GAM, it does not make sense to use -iresp to obtain the HRF because in that case the HRF would be a standard one, same everywhere. If you modeled the HRF with multiple basis functions such as TENT, SPMG2/3, etc., then -iresp would give more informative HRF (linear combination of those basis functions).

> I used the -iresp option in 3dDeconvolve and it created a HEAD+BRIK dataset
> for me. When I opened the dataset in AFNI, it ended up looking like a 2-D
> activation map. Where can I find the 1-D response function for each voxel?

You have to set the output from -iresp as Underlay, and then you can get the curves on the Graph window. Since you provided the anatomical data OutBrick_run_011+orig.* as underlay in the pictures you attached here, it's no surprise you failed to get the HRF curve on the Graph window.

HTH,
Gang