1 00:00:02,040 --> 00:00:07,040 Speaker 1: Welcome to brain Stuff from How Stuff Works. Hey, brain Stuff, 2 00:00:07,080 --> 00:00:09,799 Speaker 1: I'm Lauren Volke Bomb and today's question is would you 3 00:00:09,840 --> 00:00:13,880 Speaker 1: really stay conscious after being decapitated? Let's look first at 4 00:00:13,920 --> 00:00:18,000 Speaker 1: what consciousness is. The molecular biologist Francis Crick, one half 5 00:00:18,000 --> 00:00:20,480 Speaker 1: of the research team who discovered the structure of DNA 6 00:00:21,000 --> 00:00:23,040 Speaker 1: later in his career, came up with what he called 7 00:00:23,200 --> 00:00:27,440 Speaker 1: the astonishing hypothesis. It is crudely put, the idea that 8 00:00:27,480 --> 00:00:30,960 Speaker 1: every aspect of human consciousness, from affinity for one's family, 9 00:00:31,040 --> 00:00:33,320 Speaker 1: to a belief in God to the experience of the 10 00:00:33,360 --> 00:00:36,680 Speaker 1: color green, is merely the result of electrical activity in 11 00:00:36,680 --> 00:00:40,920 Speaker 1: our brain's neural networks. As he wrote in You're Nothing 12 00:00:40,960 --> 00:00:43,559 Speaker 1: but a Pack of neurons, at the basis of our 13 00:00:43,600 --> 00:00:48,360 Speaker 1: conscious experience are chemicals called neurotransmitters. These chemicals generate electrical 14 00:00:48,400 --> 00:00:51,199 Speaker 1: signals that form the means by which neurons communicate with 15 00:00:51,240 --> 00:00:55,040 Speaker 1: one another and ultimately form neural networks. When we stimulate 16 00:00:55,080 --> 00:00:58,520 Speaker 1: these networks, we experience the physical sensations and emotions that 17 00:00:58,560 --> 00:01:01,360 Speaker 1: make up our lives. We store these as memories to 18 00:01:01,400 --> 00:01:03,640 Speaker 1: be recalled when the neural networks that store them are 19 00:01:03,680 --> 00:01:07,399 Speaker 1: activated once more. The idea may be a bit glum, 20 00:01:07,400 --> 00:01:09,240 Speaker 1: but it forms the basis of the idea that the 21 00:01:09,280 --> 00:01:12,280 Speaker 1: electrical activity in the brain is the detectable trace of 22 00:01:12,280 --> 00:01:16,000 Speaker 1: our conscious experience by correlation, then so long as we 23 00:01:16,040 --> 00:01:19,080 Speaker 1: can detect this electrical activity through the use of technology 24 00:01:19,160 --> 00:01:21,680 Speaker 1: like the e G which measures brain waves, we can 25 00:01:21,720 --> 00:01:25,039 Speaker 1: assume that a person is experiencing consciousness. This is what 26 00:01:25,160 --> 00:01:28,080 Speaker 1: makes a two thousand eleven study from the Netherlands so troubling. 27 00:01:28,640 --> 00:01:31,560 Speaker 1: The researchers were trying to determine whether decapitation, which is 28 00:01:31,600 --> 00:01:34,920 Speaker 1: a common method of uthanizing lab rats, is humane. They 29 00:01:34,920 --> 00:01:38,240 Speaker 1: connected an EEG machine to the brains of rats, decapitated them, 30 00:01:38,319 --> 00:01:41,240 Speaker 1: and recorded the electrical activity in the brain after the event. 31 00:01:42,040 --> 00:01:44,440 Speaker 1: The researchers found that for about four seconds after being 32 00:01:44,440 --> 00:01:47,400 Speaker 1: separated from the body, the rats brains continue to generate 33 00:01:47,400 --> 00:01:51,360 Speaker 1: electrical activity between the thirteen to one hurts frequency band, 34 00:01:51,600 --> 00:01:55,800 Speaker 1: which is associated with consciousness and cognition a k A. Thinking. 35 00:01:56,720 --> 00:01:59,840 Speaker 1: This finding suggests the brain can continue to produce thoughts 36 00:01:59,840 --> 00:02:03,520 Speaker 1: and experienced sensations for at least several seconds following decapitation 37 00:02:03,720 --> 00:02:07,480 Speaker 1: in rats. Anyway, Yet, the annals of medicine following the 38 00:02:07,520 --> 00:02:11,320 Speaker 1: invention of the guillotine have some very interesting scientific observations 39 00:02:11,480 --> 00:02:15,320 Speaker 1: of human decapitation. Let's look at what happens when one 40 00:02:15,400 --> 00:02:19,359 Speaker 1: loses one's head. The circulatory system delivers oxygen and other 41 00:02:19,440 --> 00:02:22,200 Speaker 1: necessary particles via blood to the brain so that the 42 00:02:22,200 --> 00:02:25,560 Speaker 1: brain can carry out its necessary functions. Deprived of oxygen 43 00:02:25,680 --> 00:02:30,240 Speaker 1: or blood, the brain's function deteriorates rapidly. Circulation takes place 44 00:02:30,280 --> 00:02:33,720 Speaker 1: in a closed system based on a pressurized environment. Blood 45 00:02:33,720 --> 00:02:35,360 Speaker 1: is pumped in and out of the heart and past 46 00:02:35,440 --> 00:02:39,960 Speaker 1: the lungs, where it's refreshed once more. Decapitation opens this 47 00:02:40,080 --> 00:02:43,840 Speaker 1: closed system irrevocably, causing a full and massive drop in 48 00:02:43,880 --> 00:02:47,400 Speaker 1: blood pressure, leaving the brain starved of both blood and oxygen. 49 00:02:48,480 --> 00:02:50,560 Speaker 1: Depending on how the head is removed from the body, 50 00:02:50,760 --> 00:02:54,080 Speaker 1: this loss of blood and ultimately consciousness can take longer 51 00:02:54,120 --> 00:02:57,560 Speaker 1: in some modes of decapitation than in others. Several blows 52 00:02:57,560 --> 00:02:59,080 Speaker 1: to the back of the neck with a sword or 53 00:02:59,120 --> 00:03:01,560 Speaker 1: axe can lead to blood loss before the head is 54 00:03:01,600 --> 00:03:04,880 Speaker 1: fully severed from the body, but the design of the guillotine, 55 00:03:04,960 --> 00:03:08,160 Speaker 1: the execution method of choice during the French Revolution, made 56 00:03:08,160 --> 00:03:11,960 Speaker 1: severing the head cleaner and quicker. The blade and weight 57 00:03:11,960 --> 00:03:14,760 Speaker 1: assembly of the guillotine weighed more than a hundred seventy 58 00:03:14,760 --> 00:03:17,520 Speaker 1: five pounds that's eight ks, and was dropped from a 59 00:03:17,560 --> 00:03:20,480 Speaker 1: height of fourteen feet or just over four meters from 60 00:03:20,560 --> 00:03:23,800 Speaker 1: ground level onto the back of the victim's neck. Moreover, 61 00:03:23,880 --> 00:03:26,560 Speaker 1: the guillotine's blade was set within a track leading in 62 00:03:26,560 --> 00:03:28,960 Speaker 1: a direct line down to the back of the victim's neck. 63 00:03:30,040 --> 00:03:33,520 Speaker 1: There's a rumor that this superior execution technology led to 64 00:03:33,560 --> 00:03:38,160 Speaker 1: at least one case of apparent consciousness after decapitation. Executions 65 00:03:38,160 --> 00:03:42,080 Speaker 1: in eighteenth century France were public affairs, and executioners customarily 66 00:03:42,080 --> 00:03:44,320 Speaker 1: showed the head of the victim to the assembled crowd 67 00:03:44,840 --> 00:03:48,200 Speaker 1: that sometimes performed some gesture of disrespect as well, as 68 00:03:48,360 --> 00:03:51,160 Speaker 1: was the case with Charlotte Corday, a woman executed by 69 00:03:51,160 --> 00:03:55,040 Speaker 1: guillotine in seventeen ninety three after she assassinated the revolutionary 70 00:03:55,120 --> 00:03:58,800 Speaker 1: leader Jean Paul Moran. After her head was severed, the 71 00:03:58,800 --> 00:04:01,920 Speaker 1: executioner smacked its cheeks while he held it aloft, to 72 00:04:01,960 --> 00:04:05,040 Speaker 1: the astonishment of the crowd. Corday's cheeks flushed and her 73 00:04:05,040 --> 00:04:11,000 Speaker 1: facial expression changed into quote unequivocal marks of indignation. Most recently, 74 00:04:11,040 --> 00:04:14,240 Speaker 1: in nineteen eighty nine, an army veteran reported that following 75 00:04:14,280 --> 00:04:16,160 Speaker 1: a car accident that he was in with a friend, 76 00:04:16,360 --> 00:04:20,200 Speaker 1: the decapitated head of his friend changed facial expressions quote 77 00:04:20,400 --> 00:04:23,640 Speaker 1: first of shock or confusion, then to terror or grief. 78 00:04:24,640 --> 00:04:27,040 Speaker 1: Both King Charles the First and Queen Anne Boleyn are 79 00:04:27,080 --> 00:04:29,919 Speaker 1: reported to have showed signs of trying to speak following 80 00:04:29,920 --> 00:04:33,719 Speaker 1: their beheadings by executioner's swords rather than the guillotine, And 81 00:04:33,960 --> 00:04:36,720 Speaker 1: when in seventeen ninety five a German researcher by the 82 00:04:36,800 --> 00:04:38,920 Speaker 1: name of St. Summering spoke out against the use of 83 00:04:38,960 --> 00:04:42,120 Speaker 1: the guillotine, he cited reports of decapitated heads that have 84 00:04:42,200 --> 00:04:44,680 Speaker 1: ground their teeth and that the face of one decapitated 85 00:04:44,720 --> 00:04:48,320 Speaker 1: person grimaced horribly when a physician inspecting the head poked 86 00:04:48,360 --> 00:04:52,000 Speaker 1: the spinal canal with his finger. But perhaps most famous 87 00:04:52,040 --> 00:04:54,240 Speaker 1: was the study conducted in nineteen o five of the 88 00:04:54,279 --> 00:04:57,240 Speaker 1: head of an executed criminal. Over the course of twenty 89 00:04:57,240 --> 00:05:00,640 Speaker 1: five to thirty seconds of observation, the physician warded managing 90 00:05:00,680 --> 00:05:03,280 Speaker 1: to get the head to open its eyes and undeniably 91 00:05:03,320 --> 00:05:06,520 Speaker 1: focus them on the doctors twice by calling the executed 92 00:05:06,520 --> 00:05:11,320 Speaker 1: man's name. Some say that none of this proves consciousness. 93 00:05:11,640 --> 00:05:13,560 Speaker 1: The movement seen in the phase could be the result 94 00:05:13,560 --> 00:05:15,880 Speaker 1: of the voluntary muscles that control the lips and eyes 95 00:05:15,960 --> 00:05:18,880 Speaker 1: merely being in spasm after a sort of short circuit, 96 00:05:19,040 --> 00:05:22,640 Speaker 1: or from the relic of electrical activity. This is likely 97 00:05:22,640 --> 00:05:24,680 Speaker 1: true for the rest of the body, but the head 98 00:05:24,760 --> 00:05:27,240 Speaker 1: has the distinction of housing the brain, which is the 99 00:05:27,320 --> 00:05:30,440 Speaker 1: seat of consciousness. The brain receives no drama from a 100 00:05:30,520 --> 00:05:34,159 Speaker 1: clean decapitation, and may therefore continue to function until blood 101 00:05:34,160 --> 00:05:38,520 Speaker 1: loss causes unconsciousness and death. We know that chickens often 102 00:05:38,560 --> 00:05:42,160 Speaker 1: walk around for several seconds after decapitation. The Dutch rat 103 00:05:42,240 --> 00:05:45,320 Speaker 1: study mentioned earlier suggests a length of perhaps four seconds. 104 00:05:46,120 --> 00:05:48,359 Speaker 1: Other studies of small animals have found up to twenty 105 00:05:48,440 --> 00:05:51,560 Speaker 1: nine seconds, but any amount of time would be horrific. 106 00:05:52,040 --> 00:05:54,040 Speaker 1: Take a moment to count off four seconds while you 107 00:05:54,120 --> 00:05:56,520 Speaker 1: look around the room. You'll likely find you can take 108 00:05:56,520 --> 00:06:00,480 Speaker 1: in quite a bit visually and orally during that time. However, 109 00:06:00,560 --> 00:06:03,080 Speaker 1: we may never fully know if a human remains conscious 110 00:06:03,120 --> 00:06:06,760 Speaker 1: after the head is lost. As author Alan Bellows points out, 111 00:06:07,240 --> 00:06:16,640 Speaker 1: further scientific observation of human decapitation is unlikely. Today's episode 112 00:06:16,640 --> 00:06:20,000 Speaker 1: was written by Josh Clark and produced by Tyler Clang Josh, 113 00:06:20,000 --> 00:06:21,960 Speaker 1: who you may have heard on a little show called 114 00:06:21,960 --> 00:06:24,520 Speaker 1: Stuff You Should Know, has a new podcast coming out 115 00:06:24,600 --> 00:06:27,680 Speaker 1: called The End of the World. If you enjoy slightly glum, 116 00:06:27,680 --> 00:06:30,719 Speaker 1: but nonetheless fascinating discussions like the one from today's episode, 117 00:06:30,800 --> 00:06:32,800 Speaker 1: go check it out. The first episode of the End 118 00:06:32,839 --> 00:06:35,280 Speaker 1: of the World drops November seven, and the trailer is 119 00:06:35,360 --> 00:06:38,520 Speaker 1: up everywhere you get your podcasts, and of course, for 120 00:06:38,640 --> 00:06:41,200 Speaker 1: more on this and lots of other curious topics, visit 121 00:06:41,240 --> 00:06:54,599 Speaker 1: our home planet, how Stuff works dot com.