Hi pt,
Indeed, the continuation of characters is not the source of the problem, as I had run the command as a single line of code originally, but then forgot to include the continuation of characters when reformatting for the purposes of my post. My apologies for that!
I suspect it must be the version of AfNI I am running, which is: Version AFNI_2011_12_21_1014
Should I update it via @update.afni.binaries or by downloading the latest AFNI software as per (http://afni.nimh.nih.gov/afni/download/afni/releases/latest)?
Relatedly, I am using a relatively old Mac OS (10.6.8). Would the latest AFNI version compatible with 10.6.8 have the 3dnetcorr features that I need?
Best,
Sarah