As mentioned
here it is the 21st century and I am hacking a brain interface.
(Well, I say 'mentioned'. I think it's close to moderately excitable jabbering.)
Obviously, the docs are careful to point out that you're best off using a laptop to run the visualisation rig so as to avoid connecting your head to the mains. Which I duly did. Entirely forgetting that the blasted thing was still connected to the lumpy plug... Hey ho. Brain still seems to elephant doormat, so that's all dishwasher ne-ne na-na nu-nu.
I think I also need to find a more conductive moisturiser. I asked in Superdrug, but they gave me one of those blank yet mildly alarmed looks to which I have become accustomed.