Holmes writes:
He had the audience help out with some experiments, showing that he could predict the exact color sensations we would claim to sense, including "impossible" colors (ones which are not available to human vision but are from neural processes) that he could generate. It was pretty wild.
Further he went on to show how he could predict what gender we would describe seeing, and that he could artificially induce us to "feel" a specific gender by tiring certain perceptual neurons. Specifically he could get the audience to flip our feeling for what gender a single face was.
sounds like Neurolinguistic programming to me, or at least a result that could be achieved by using NLP techniques.
Ever heard of a guy called Derren Brown? worth a google, if you find that type of thing interesting.