Johan Lehrer and Javier Zarracina created these graphics for the Boston Globe to illustrate how easily the senses can be tricked into perceiving things we know can't be real. One need not resort to psychedelics like LSD or mescaline to experience hallucination and altered perceptions.
Zarracina crafted the graphics and Leher wrote the text for these five tricks to “hack your brain.” Two of these will produce visual hallucinations, and the other three create sensory illusions. While the visual experiments can be performed alone, two of the sensory experiments require a friend. The other requires that the performer is wounded.
Although not presented in the slideshow, (and not advisable for home trial) magnetic fields have debatably caused hallucinations. Specifically, Micheal Persinger, a Korean neuroscientist, developed a device that when “placed on the head of an experimental subject, generates very weak fluctuating magnetic fields.” Because many subjects reported mystical experiences during trials, the device was dubbed “The God Helmet.”