1 00:00:03,279 --> 00:00:05,640 Speaker 1: Welcome to Stuff to Blow Your Mind, a production of 2 00:00:05,640 --> 00:00:11,319 Speaker 1: iHeart Radio. Hi, my name is Joe McCormick, and this 3 00:00:11,560 --> 00:00:14,560 Speaker 1: is the Artifact, a short form series from Stuff to 4 00:00:14,560 --> 00:00:19,000 Speaker 1: Blow Your Mind, focusing on particular objects, ideas, and moments 5 00:00:19,000 --> 00:00:25,720 Speaker 1: in time. It's well known that visual hallucinations can be 6 00:00:25,760 --> 00:00:31,760 Speaker 1: induced by psychedelic compounds like LSD, d MT, mescaline, and psilocybin. 7 00:00:32,440 --> 00:00:36,160 Speaker 1: But according to a now copious body of research, there's 8 00:00:36,200 --> 00:00:40,240 Speaker 1: a fairly reliable and less chemically exotic way to make 9 00:00:40,240 --> 00:00:43,960 Speaker 1: people with otherwise typical vision see things that aren't there 10 00:00:44,840 --> 00:00:49,879 Speaker 1: deprive the eyes of light and weight. One example. In 11 00:00:49,920 --> 00:00:52,640 Speaker 1: two thousand four, a study was published in the Journal 12 00:00:52,640 --> 00:00:57,360 Speaker 1: of neuro Optomology by Lotvie Marabet, Denise McGuire, Aisling Ward, 13 00:00:57,600 --> 00:01:03,520 Speaker 1: Karen Alterescu, Robert Stickle, and Alvaro pascual leone called visual 14 00:01:03,560 --> 00:01:09,520 Speaker 1: hallucinations during prolonged blindfolding insided subjects. This study actually took 15 00:01:09,520 --> 00:01:12,319 Speaker 1: place within the bounds of a larger study about learning 16 00:01:12,400 --> 00:01:16,520 Speaker 1: and brain plasticity under sensory deprivation. A couple of the 17 00:01:16,560 --> 00:01:20,280 Speaker 1: test groups of that larger study required subjects to wear 18 00:01:20,319 --> 00:01:24,760 Speaker 1: a blindfold for ninety six hours straight. Now, this wasn't 19 00:01:24,800 --> 00:01:27,440 Speaker 1: just a strip of cloth tied around the eyes. It 20 00:01:27,560 --> 00:01:30,920 Speaker 1: was a sort of power blindfold that prevented any light 21 00:01:31,000 --> 00:01:35,160 Speaker 1: perception whatsoever. Quote It was held in place by a 22 00:01:35,280 --> 00:01:39,959 Speaker 1: velcro strap and further secured by ace bandages. The blindfold 23 00:01:39,959 --> 00:01:42,720 Speaker 1: permitted full motion of the eyes, as well as opening 24 00:01:42,720 --> 00:01:46,800 Speaker 1: and closing of eyelids. Potential tampering with the blindfold by 25 00:01:46,800 --> 00:01:49,680 Speaker 1: the subjects was controlled with the use of a piece 26 00:01:49,720 --> 00:01:53,640 Speaker 1: of photographic paper attached to the inside of the blindfold. 27 00:01:54,320 --> 00:01:59,120 Speaker 1: All subjects were issued a handheld microcassette recorder with automatic 28 00:01:59,200 --> 00:02:03,280 Speaker 1: date times stamping, and directed to report their thoughts, feelings, 29 00:02:03,280 --> 00:02:06,600 Speaker 1: and perceptions related to the experiment throughout the day as 30 00:02:06,640 --> 00:02:13,400 Speaker 1: frequently as they desired. Now, what was so interesting about 31 00:02:13,440 --> 00:02:17,120 Speaker 1: these micro cassette diaries is that, without prompting, out of 32 00:02:17,200 --> 00:02:24,000 Speaker 1: thirteen subjects total, ten reported experiencing visual hallucinations on average 33 00:02:24,000 --> 00:02:28,040 Speaker 1: after about a day of blindfolding. These visions varied a lot, 34 00:02:28,320 --> 00:02:32,600 Speaker 1: from simple perceptions of flashing lights known as phosphenes, to 35 00:02:32,760 --> 00:02:38,400 Speaker 1: complex imagery like people, environments, and ornate objects. Subject four, 36 00:02:38,560 --> 00:02:41,680 Speaker 1: a twenty three year old man, reported seeing a strange 37 00:02:41,680 --> 00:02:47,080 Speaker 1: assortment of vivid geometrical shapes, warping jigsaw puzzle pieces, a 38 00:02:47,200 --> 00:02:50,840 Speaker 1: triangle with bold dots at each vertex, and quote a 39 00:02:50,960 --> 00:02:55,280 Speaker 1: large X with a light shining underneath it. Subject eight, 40 00:02:55,320 --> 00:03:00,840 Speaker 1: a twenty year old woman saw cities, skies, kaleidoscopes, lions, 41 00:03:00,960 --> 00:03:05,160 Speaker 1: and a butterfly that became a sunset. Quote if there 42 00:03:05,240 --> 00:03:07,760 Speaker 1: is a sunset or a sunrise, I couldn't look at 43 00:03:07,800 --> 00:03:10,840 Speaker 1: the sun because it was too bright. It would seem 44 00:03:10,880 --> 00:03:13,080 Speaker 1: like all of this light would just collect where the 45 00:03:13,120 --> 00:03:17,079 Speaker 1: sun was, and I just could not look there. Subject six, 46 00:03:17,200 --> 00:03:21,400 Speaker 1: a thirty four year old man reported intricate visual hallucinations 47 00:03:21,400 --> 00:03:26,280 Speaker 1: while listening to music, particularly Mozart. First he saw skulls 48 00:03:26,320 --> 00:03:29,840 Speaker 1: and ceremonial masks, then the image of an old woman 49 00:03:29,960 --> 00:03:33,520 Speaker 1: sitting in an airplane seat whose face transformed into the 50 00:03:33,560 --> 00:03:37,160 Speaker 1: face of a rodent. Subject to A twenty four year 51 00:03:37,200 --> 00:03:42,000 Speaker 1: old man saw all kinds of imagery, flashing lights, lamps, trees, 52 00:03:42,360 --> 00:03:46,840 Speaker 1: mirrors and full landscapes, ornate buildings of green, white marble, 53 00:03:46,920 --> 00:03:50,880 Speaker 1: and cartoon figures, but he also perceived obstacles in his 54 00:03:51,000 --> 00:03:54,560 Speaker 1: path while walking from place to place, believing while walking 55 00:03:54,560 --> 00:03:57,840 Speaker 1: outside that he saw ditches in the dirt stones and 56 00:03:57,960 --> 00:04:01,840 Speaker 1: streams of water. One interesting variation was that some of 57 00:04:01,880 --> 00:04:07,160 Speaker 1: the hallucinations were context appropriate. Subject one, a twenty nine 58 00:04:07,240 --> 00:04:11,000 Speaker 1: year old woman, experienced one hallucination twelve hours after the 59 00:04:11,040 --> 00:04:14,640 Speaker 1: blindfolding began. She stood in front of a mirror which 60 00:04:14,640 --> 00:04:17,600 Speaker 1: she knew was there, but of course couldn't see, and 61 00:04:17,680 --> 00:04:21,360 Speaker 1: suddenly a face appeared where her reflection should have been. 62 00:04:21,800 --> 00:04:25,000 Speaker 1: Only it wasn't her face, but quote a green face 63 00:04:25,120 --> 00:04:29,279 Speaker 1: with big eyes. Subject three, a twenty four year old woman, 64 00:04:29,320 --> 00:04:32,640 Speaker 1: had been napping when her sister arrived to visit. As 65 00:04:32,640 --> 00:04:35,560 Speaker 1: her sister entered the room, the subjects saw quote a 66 00:04:35,600 --> 00:04:39,920 Speaker 1: splotch of light in the exact form of Elvis Presley. 67 00:04:40,040 --> 00:04:42,760 Speaker 1: In both of these cases, the brain saw a human 68 00:04:42,839 --> 00:04:45,680 Speaker 1: figure where it knew by a combination of memory and 69 00:04:45,720 --> 00:04:49,200 Speaker 1: other senses that one could be found, only it didn't 70 00:04:49,240 --> 00:04:52,400 Speaker 1: see the correct human figure. But other visions of this 71 00:04:52,480 --> 00:04:56,000 Speaker 1: kind were more accurate. Subject five, a twenty nine year 72 00:04:56,040 --> 00:04:59,159 Speaker 1: old woman, reported, on the second day, quote, I have 73 00:04:59,360 --> 00:05:02,280 Speaker 1: the sensation and that I can see my hands in 74 00:05:02,360 --> 00:05:05,720 Speaker 1: my arms moving when I moved them, and leaving an 75 00:05:05,720 --> 00:05:09,719 Speaker 1: illuminated trail when she reached out to pick up an object. 76 00:05:09,800 --> 00:05:12,800 Speaker 1: She realized she could see her hands doing what they 77 00:05:12,800 --> 00:05:15,960 Speaker 1: were doing, even though there was no light reaching her eyes. 78 00:05:16,839 --> 00:05:20,480 Speaker 1: Subject ten, a twenty one year old woman, experienced something 79 00:05:20,520 --> 00:05:23,720 Speaker 1: similar as she was eating a meal. She reached out 80 00:05:23,760 --> 00:05:26,400 Speaker 1: to a water pitcher to pour herself a drink and 81 00:05:26,480 --> 00:05:30,400 Speaker 1: suddenly reported that she could see what she was doing. Quote, 82 00:05:30,640 --> 00:05:33,240 Speaker 1: I felt like I was seeing the pitcher while I 83 00:05:33,279 --> 00:05:37,560 Speaker 1: was pouring the water. These last variations about context dependent 84 00:05:37,640 --> 00:05:40,839 Speaker 1: hallucinations were the most interesting part of the study to me, 85 00:05:41,320 --> 00:05:44,240 Speaker 1: since they might cause us to question what we mean 86 00:05:44,400 --> 00:05:48,719 Speaker 1: when we distinguish hallucination from real sight. The fact that 87 00:05:48,760 --> 00:05:51,960 Speaker 1: our eyes receive no light might not mean that we 88 00:05:52,040 --> 00:05:55,640 Speaker 1: can't see. This type of lightless vision of one's own 89 00:05:55,680 --> 00:05:59,000 Speaker 1: body has been observed in other contexts. Just one example, 90 00:05:59,360 --> 00:06:02,440 Speaker 1: spelunk is in the total darkness of a deep cave 91 00:06:02,839 --> 00:06:06,000 Speaker 1: sometimes report that they can see their own hands and 92 00:06:06,279 --> 00:06:09,479 Speaker 1: arms and the movements of their own body. This is 93 00:06:09,520 --> 00:06:13,880 Speaker 1: sometimes known as the spelunkers illusion. The eyes sense light, 94 00:06:14,200 --> 00:06:17,600 Speaker 1: but seeing happens in the brain, and it turns out 95 00:06:17,640 --> 00:06:20,960 Speaker 1: the visual cortex can not only mistakenly see things that 96 00:06:21,000 --> 00:06:24,520 Speaker 1: aren't actually present in the case of a hallucination, it 97 00:06:24,560 --> 00:06:28,880 Speaker 1: can also see things that are present accurately when the 98 00:06:28,920 --> 00:06:32,039 Speaker 1: brain is informed of them by sources other than light, 99 00:06:32,480 --> 00:06:36,920 Speaker 1: such as hearing, touch, appropriate reception, and memory, which is 100 00:06:36,960 --> 00:06:39,680 Speaker 1: in fact consistent with lots of research showing that people 101 00:06:39,760 --> 00:06:43,599 Speaker 1: with permanent blindness often recruit the visual cortex of the 102 00:06:43,640 --> 00:06:47,680 Speaker 1: brain to do things like make mental maps of environments, 103 00:06:47,720 --> 00:06:51,200 Speaker 1: even though those maps are not based on light perceived 104 00:06:51,240 --> 00:06:54,000 Speaker 1: through the eyes. So what does it mean to see? 105 00:07:00,080 --> 00:07:02,840 Speaker 1: Tune into new editions of the artifact each week, hosted 106 00:07:02,880 --> 00:07:05,960 Speaker 1: by the Robert or myself as always, You can email 107 00:07:06,040 --> 00:07:19,520 Speaker 1: us at contact at stuff to Blow your Mind dot com. 108 00:07:19,520 --> 00:07:21,360 Speaker 1: Stuff to Blow Your Mind is a production of I 109 00:07:21,480 --> 00:07:24,360 Speaker 1: Heart Radio. For more podcasts for my heart Radio, visit 110 00:07:24,360 --> 00:07:26,960 Speaker 1: the i heart Radio app, Apple Podcasts, or wherever you 111 00:07:27,000 --> 00:07:28,200 Speaker 1: listen to your favorite shows.