afni.nimh.nih.gov

I took a quick look at the BrikLoad.m source code, and it looks fairly well described there. I think setting Opt.format = vector will do what you want. As Peter said, we haven't really done any updates to this in years. Reshaping in Matlab should also work. Another way is to use 3dmaskdump to dump the values into a text file and then read the text file into Matlab. That's fairly slow though, and you will probably find the other choices more efficient.