The Artifact Revisited: The Psychedelic Blindfold

But according to a now copious body of research, there's a fairly reliable and less chemically exotic way to make people with otherwise typical vision see things that aren't there deprive the eyes of light and weight. One example. In two thousand four, a study was published in the Journal of neuro Optomology by Lotvie Marabet, Denise McGuire, Aisling Ward, Karen Alterescu, Robert Stickle, and Alvaro pascual leone called visual

hallucinations during prolonged blindfolding insided subjects. This study actually took place within the bounds of a larger study about learning and brain plasticity under sensory deprivation. A couple of the test groups of that larger study required subjects to wear a blindfold for ninety six hours straight. Now, this wasn't just a strip of cloth tied around the eyes. It was a sort of power blindfold that prevented any light perception whatsoever. Quote It was held in place by a

velcro strap and further secured by ace bandages. The blindfold permitted full motion of the eyes, as well as opening and closing of eyelids. Potential tampering with the blindfold by the subjects was controlled with the use of a piece of photographic paper attached to the inside of the blindfold.

All subjects were issued a handheld microcassette recorder with automatic date times stamping, and directed to report their thoughts, feelings, and perceptions related to the experiment throughout the day as frequently as they desired. Now, what was so interesting about these micro cassette diaries is that, without prompting, out of thirteen subjects total, ten reported experiencing visual hallucinations on average

after about a day of blindfolding. These visions varied a lot, from simple perceptions of flashing lights known as phosphenes, to complex imagery like people, environments, and ornate objects. Subject four, a twenty three year old man, reported seeing a strange assortment of vivid geometrical shapes, warping jigsaw puzzle pieces, a triangle with bold dots at each vertex, and quote a

large X with a light shining underneath it. Subject eight, a twenty year old woman saw cities, skies, kaleidoscopes, lions, and a butterfly that became a sunset. Quote if there is a sunset or a sunrise, I couldn't look at the sun because it was too bright. It would seem like all of this light would just collect where the sun was, and I just could not look there. Subject six, a thirty four year old man reported intricate visual hallucinations

while listening to music, particularly Mozart. First he saw skulls and ceremonial masks, then the image of an old woman sitting in an airplane seat whose face transformed into the

face of a rodent. Subject to A twenty four year old man saw all kinds of imagery, flashing lights, lamps, trees, mirrors and full landscapes, ornate buildings of green, white marble, and cartoon figures, but he also perceived obstacles in his path while walking from place to place, believing while walking outside that he saw ditches in the dirt stones and streams of water. One interesting variation was that some of

the hallucinations were context appropriate. Subject one, a twenty nine year old woman, experienced one hallucination twelve hours after the blindfolding began. She stood in front of a mirror which she knew was there, but of course couldn't see, and suddenly a face appeared where her reflection should have been. Only it wasn't her face, but quote a green face with big eyes. Subject three, a twenty four year old woman,

had been napping when her sister arrived to visit. As her sister entered the room, the subjects saw quote a splotch of light in the exact form of Elvis Presley. In both of these cases, the brain saw a human figure where it knew by a combination of memory and other senses that one could be found, only it didn't see the correct human figure. But other visions of this

kind were more accurate. Subject five, a twenty nine year old woman, reported, on the second day, quote, I have the sensation and that I can see my hands in my arms moving when I moved them, and leaving an illuminated trail when she reached out to pick up an object. She realized she could see her hands doing what they were doing, even though there was no light reaching her eyes. Subject ten, a twenty one year old woman, experienced something

similar as she was eating a meal. She reached out to a water pitcher to pour herself a drink and suddenly reported that she could see what she was doing. Quote, I felt like I was seeing the pitcher while I was pouring the water. These last variations about context dependent hallucinations were the most interesting part of the study to me, since they might cause us to question what we mean

when we distinguish hallucination from real sight. The fact that our eyes receive no light might not mean that we can't see. This type of lightless vision of one's own body has been observed in other contexts. Just one example, spelunk is in the total darkness of a deep cave sometimes report that they can see their own hands and arms and the movements of their own body. This is

sometimes known as the spelunkers illusion. The eyes sense light, but seeing happens in the brain, and it turns out the visual cortex can not only mistakenly see things that aren't actually present in the case of a hallucination, it can also see things that are present accurately when the brain is informed of them by sources other than light, such as hearing, touch, appropriate reception, and memory, which is in fact consistent with lots of research showing that people

with permanent blindness often recruit the visual cortex of the brain to do things like make mental maps of environments, even though those maps are not based on light perceived through the eyes. So what does it mean to see? Tune into new editions of the artifact each week, hosted by the Robert or myself as always, You can email us at contact at stuff to Blow your Mind dot com. Stuff to Blow Your Mind is a production of I

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