Kirk 1974b Zombie Experiment?

I was doing a little research for a project and came across a website, http://plato.stanford.edu/entries/zombies/. I was reading and as I scrolled down I saw an "Arguements For" section. It tells about a "Kirk 1974b" experiment. I was wondering if this actually happened in an experiment or if it was just a theory or hypothesis. Can anyone clear this up? Thanks.