Hello,

I apologize for this simplistic question, as I am quite new to AFNI. I've been searching this forum and the documentation extensively, but am still unsure of the answer to my question.

I'd like to estimate the area under the curve of the BOLD response in response to different types of images. Our data have already been processed using 3dDeconvolve with a SIN function, using the -iresp option. In the documentation it indicates that the iresp option estimates the HRF at each voxel at each time point, but I don't know what the estimate means - is it the peak amplitude? the auc of the HRF?

Now, I know that if I average together a few sequential sub-briks from one of the iresp files and then divide by the baseline, this gives me a 'percent signal change' file. My question is, is this the average percent signal change, or is it an estimate of the auc? Not knowing for sure what the iresp sub-brik files represent, I am unsure.

Thanks for all your help! If there is a link or a previous message board response that I've missed, feel free to send me there instead :)