For example, the invisibility trick of that young, dumb scrambler— the one who restricted its movement to the gaps in Human vision— occured to me while reading about something called inattentional blindness. A Russian guy called Yarbus was the first to figure out the whole saccadal glitch in Human vision, back in the nineteen sixties [15]. Since then, a variety of researchers have made objects pop in and out of the visual field unnoticed, conducted conversations with hapless subjects who never realised that their conversational partner had changed halfway through the interview, and generally proven that the Human brain just fails to notice an awful lot of what's going on around it [16, 17, 18]. Check out the demos at the website of the Visual Cognition Lab at the University of Illinois [19] and you'll see what I mean. This really is rather mind-blowing, people. There could be Scientologists walking among us right now and if they moved just right, we'd never even see them.
Most of the psychoses, syndromes, and hallucinations described herein are real, and are described in detail by Metzinger [20], Wegner [21], and/or Saks [22] (see also Sentience/Intelligence, below). Others (e.g. Grey Syndrome) have not yet made their way into the DSM [23]—truth be told, I invented a couple— but are nonetheless based on actual experimental evidence. Depending upon whom you believe, the judicious application of magnetic fields to the brain can provoke everything from religious rapture [24] to a sense of being abducted by aliens [25]. Transcranial magnetic stimulation can change mood, induce blindness [26], or target the speech centers (making one unable to pronounce verbs, for example, while leaving the nouns unimpaired) [27]. Memory and learning can be enhanced (or impaired), and the US Government is presently funding research into wearable TMS gear for—you guessed it— military purposes [28].
Sometimes electrical stimulation of the brain induces "alien hand syndrome" — the involuntary movement of the body against the will of the «person» allegedly in control [29]. Other times it provokes equally involuntary movements, which subjects nonetheless insist they «chose» to perform despite overwhelming empirical evidence to the contrary [30]. Put all this together with the fact that the body begins to act before the brain even «decides» to move [31] (but see [32, 33]), and the whole concept of free will—despite the undeniable subjective feeling that it's real—begins to look a teeny bit silly, even outside the influence of alien artefacts.
While electromagnetic stimulation is currently the most trendy approach to hacking the brain, it's hardly the only one. Gross physical disturbances ranging from tumors [34] to tamping irons [35] can turn normal people into psychopaths and pedophiles (hence that new persona sprouting in Susan James's head). Spirit possession and rapture can be induced through the sheer emotional bump-and-grind of religious rituals, using no invasive neurological tools at all (and not even necessarily any pharmacological ones) [21]. People can even develop a sense of ownership of body parts that aren't theirs, can be convinced that a rubber hand is their real one [36]. Vision trumps propioreception: a prop limb, subtly manipulated, is enough to convince us that we're doing one thing while in fact we're doing something else entirely [37, 38].
The latest tool in this arsenal is ultrasound: less invasive than electromagnetics, more precise than charismatic revival, it can be used to boot up brain activity [39] without any of those pesky electrodes or magnetic hairnets. In Blindsight it serves as a convenient back door to explain why Rorschach's hallucinations persist even in the presence of Faraday shielding— but in the here and now, Sony has been renewing an annual patent for a machine which uses ultrasonics to implant "sensory experiences" directly into the brain [40]. They're calling it an entertainment device with massive applications for online gaming. Uh huh. And if you can implant sights and sounds into someone's head from a distance, why not implant political beliefs and the irresistable desire for a certain brand of beer while you're at it?
Are We There Yet?