Hi buster,
I had the test a couple of weeks ago. It made me feel ready for a kip! :o (they should put some rave music on at the same time)!!
Im not sure how you are supposed to react, but I passed without any probs. (not sure it is the best test to have straight before the Eye examination though)!!
Sure you'll be fine. (i was told that there was a brain in my head)!