1 00:00:00,000 --> 00:00:01,939 how do we know that we experienced the 2 00:00:01,939 --> 00:00:01,949 how do we know that we experienced the 3 00:00:01,949 --> 00:00:04,039 how do we know that we experienced the real-world facts we probably don't 4 00:00:04,039 --> 00:00:04,049 real-world facts we probably don't 5 00:00:04,049 --> 00:00:05,749 real-world facts we probably don't everything that we perceive everything 6 00:00:05,749 --> 00:00:05,759 everything that we perceive everything 7 00:00:05,759 --> 00:00:08,210 everything that we perceive everything that we experience is a result of the 8 00:00:08,210 --> 00:00:08,220 that we experience is a result of the 9 00:00:08,220 --> 00:00:10,190 that we experience is a result of the brain interpreting the sensory 10 00:00:10,190 --> 00:00:10,200 brain interpreting the sensory 11 00:00:10,200 --> 00:00:11,600 brain interpreting the sensory information that comes in in a 12 00:00:11,600 --> 00:00:11,610 information that comes in in a 13 00:00:11,610 --> 00:00:14,060 information that comes in in a particular way I'm an Elsa I'm a 14 00:00:14,060 --> 00:00:14,070 particular way I'm an Elsa I'm a 15 00:00:14,070 --> 00:00:15,499 particular way I'm an Elsa I'm a professor of neuroscience at the 16 00:00:15,499 --> 00:00:15,509 professor of neuroscience at the 17 00:00:15,509 --> 00:00:17,689 professor of neuroscience at the University of Sussex in the UK now you 18 00:00:17,689 --> 00:00:17,699 University of Sussex in the UK now you 19 00:00:17,699 --> 00:00:21,019 University of Sussex in the UK now you could say that all of our experiences 20 00:00:21,019 --> 00:00:21,029 could say that all of our experiences 21 00:00:21,029 --> 00:00:22,670 could say that all of our experiences are all hallucinating it's just that 22 00:00:22,670 --> 00:00:22,680 are all hallucinating it's just that 23 00:00:22,680 --> 00:00:25,310 are all hallucinating it's just that whenever we agree about what's out there 24 00:00:25,310 --> 00:00:25,320 whenever we agree about what's out there 25 00:00:25,320 --> 00:00:27,769 whenever we agree about what's out there that's what we call reality the brain 26 00:00:27,769 --> 00:00:27,779 that's what we call reality the brain 27 00:00:27,779 --> 00:00:31,040 that's what we call reality the brain brings to bear its prior expectations 28 00:00:31,040 --> 00:00:31,050 brings to bear its prior expectations 29 00:00:31,050 --> 00:00:33,020 brings to bear its prior expectations about what's out there in order to 30 00:00:33,020 --> 00:00:33,030 about what's out there in order to 31 00:00:33,030 --> 00:00:35,510 about what's out there in order to interpret this massive noisy and 32 00:00:35,510 --> 00:00:35,520 interpret this massive noisy and 33 00:00:35,520 --> 00:00:37,520 interpret this massive noisy and ambiguous sensory information that it 34 00:00:37,520 --> 00:00:37,530 ambiguous sensory information that it 35 00:00:37,530 --> 00:00:39,590 ambiguous sensory information that it continually encounters perception 36 00:00:39,590 --> 00:00:39,600 continually encounters perception 37 00:00:39,600 --> 00:00:42,200 continually encounters perception instead of just being a reflection of 38 00:00:42,200 --> 00:00:42,210 instead of just being a reflection of 39 00:00:42,210 --> 00:00:43,819 instead of just being a reflection of what's actually there in the world is 40 00:00:43,819 --> 00:00:43,829 what's actually there in the world is 41 00:00:43,829 --> 00:00:45,650 what's actually there in the world is always this active process of 42 00:00:45,650 --> 00:00:45,660 always this active process of 43 00:00:45,660 --> 00:00:48,020 always this active process of interpretation it's easy to assume that 44 00:00:48,020 --> 00:00:48,030 interpretation it's easy to assume that 45 00:00:48,030 --> 00:00:50,720 interpretation it's easy to assume that we see with our eyes in fact we see with 46 00:00:50,720 --> 00:00:50,730 we see with our eyes in fact we see with 47 00:00:50,730 --> 00:00:52,189 we see with our eyes in fact we see with our brains our eyes are of course 48 00:00:52,189 --> 00:00:52,199 our brains our eyes are of course 49 00:00:52,199 --> 00:00:55,100 our brains our eyes are of course necessary but what we actually end up 50 00:00:55,100 --> 00:00:55,110 necessary but what we actually end up 51 00:00:55,110 --> 00:00:57,529 necessary but what we actually end up perceiving is much more a product of how 52 00:00:57,529 --> 00:00:57,539 perceiving is much more a product of how 53 00:00:57,539 --> 00:00:59,479 perceiving is much more a product of how our brain interprets all this 54 00:00:59,479 --> 00:00:59,489 our brain interprets all this 55 00:00:59,489 --> 00:01:02,299 our brain interprets all this information from the eyes than the eyes 56 00:01:02,299 --> 00:01:02,309 information from the eyes than the eyes 57 00:01:02,309 --> 00:01:04,880 information from the eyes than the eyes being this window into a an objective 58 00:01:04,880 --> 00:01:04,890 being this window into a an objective 59 00:01:04,890 --> 00:01:07,550 being this window into a an objective external reality and when the balance is 60 00:01:07,550 --> 00:01:07,560 external reality and when the balance is 61 00:01:07,560 --> 00:01:08,990 external reality and when the balance is disturbed between how the brain 62 00:01:08,990 --> 00:01:09,000 disturbed between how the brain 63 00:01:09,000 --> 00:01:11,090 disturbed between how the brain interprets sensory information and what 64 00:01:11,090 --> 00:01:11,100 interprets sensory information and what 65 00:01:11,100 --> 00:01:12,950 interprets sensory information and what the sensory information actually is well 66 00:01:12,950 --> 00:01:12,960 the sensory information actually is well 67 00:01:12,960 --> 00:01:15,080 the sensory information actually is well that's when people start to see things 68 00:01:15,080 --> 00:01:15,090 that's when people start to see things 69 00:01:15,090 --> 00:01:16,999 that's when people start to see things that other people do and that's what we 70 00:01:16,999 --> 00:01:17,009 that other people do and that's what we 71 00:01:17,009 --> 00:01:19,399 that other people do and that's what we call hallucination when you look at it a 72 00:01:19,399 --> 00:01:19,409 call hallucination when you look at it a 73 00:01:19,409 --> 00:01:21,230 call hallucination when you look at it a cloud and sometimes you can see faces in 74 00:01:21,230 --> 00:01:21,240 cloud and sometimes you can see faces in 75 00:01:21,240 --> 00:01:22,370 cloud and sometimes you can see faces in clouds now that's a kind of 76 00:01:22,370 --> 00:01:22,380 clouds now that's a kind of 77 00:01:22,380 --> 00:01:25,310 clouds now that's a kind of hallucination other people who will see 78 00:01:25,310 --> 00:01:25,320 hallucination other people who will see 79 00:01:25,320 --> 00:01:27,109 hallucination other people who will see things that really other people don't 80 00:01:27,109 --> 00:01:27,119 things that really other people don't 81 00:01:27,119 --> 00:01:29,420 things that really other people don't see that's just a different balance that 82 00:01:29,420 --> 00:01:29,430 see that's just a different balance that 83 00:01:29,430 --> 00:01:32,630 see that's just a different balance that they have between how their prior 84 00:01:32,630 --> 00:01:32,640 they have between how their prior 85 00:01:32,640 --> 00:01:34,969 they have between how their prior expectations influence the sensory data 86 00:01:34,969 --> 00:01:34,979 expectations influence the sensory data 87 00:01:34,979 --> 00:01:37,850 expectations influence the sensory data that comes in another aspect of this is 88 00:01:37,850 --> 00:01:37,860 that comes in another aspect of this is 89 00:01:37,860 --> 00:01:40,460 that comes in another aspect of this is when you take things like psychedelic 90 00:01:40,460 --> 00:01:40,470 when you take things like psychedelic 91 00:01:40,470 --> 00:01:42,620 when you take things like psychedelic drugs that also leads people to have 92 00:01:42,620 --> 00:01:42,630 drugs that also leads people to have 93 00:01:42,630 --> 00:01:44,899 drugs that also leads people to have unusual experiences to see things that 94 00:01:44,899 --> 00:01:44,909 unusual experiences to see things that 95 00:01:44,909 --> 00:01:46,789 unusual experiences to see things that aren't there again it doesn't mean that 96 00:01:46,789 --> 00:01:46,799 aren't there again it doesn't mean that 97 00:01:46,799 --> 00:01:48,920 aren't there again it doesn't mean that these things really exist it just means 98 00:01:48,920 --> 00:01:48,930 these things really exist it just means 99 00:01:48,930 --> 00:01:50,270 these things really exist it just means that your brain is working in a 100 00:01:50,270 --> 00:01:50,280 that your brain is working in a 101 00:01:50,280 --> 00:01:52,219 that your brain is working in a different way so that it's prior 102 00:01:52,219 --> 00:01:52,229 different way so that it's prior 103 00:01:52,229 --> 00:01:54,109 different way so that it's prior expectations come to dominate the 104 00:01:54,109 --> 00:01:54,119 expectations come to dominate the 105 00:01:54,119 --> 00:01:56,690 expectations come to dominate the sensory information we can see a number 106 00:01:56,690 --> 00:01:56,700 sensory information we can see a number 107 00:01:56,700 --> 00:01:58,910 sensory information we can see a number of things that happen in the brain on 108 00:01:58,910 --> 00:01:58,920 of things that happen in the brain on 109 00:01:58,920 --> 00:02:00,920 of things that happen in the brain on psychedelics one of the things that 110 00:02:00,920 --> 00:02:00,930 psychedelics one of the things that 111 00:02:00,930 --> 00:02:03,410 psychedelics one of the things that happens is the brain generally becomes a 112 00:02:03,410 --> 00:02:03,420 happens is the brain generally becomes a 113 00:02:03,420 --> 00:02:06,319 happens is the brain generally becomes a bit more disorganized normally in the 114 00:02:06,319 --> 00:02:06,329 bit more disorganized normally in the 115 00:02:06,329 --> 00:02:08,990 bit more disorganized normally in the brain different parts of the brain have 116 00:02:08,990 --> 00:02:09,000 brain different parts of the brain have 117 00:02:09,000 --> 00:02:11,690 brain different parts of the brain have activity that correlates so we see all 118 00:02:11,690 --> 00:02:11,700 activity that correlates so we see all 119 00:02:11,700 --> 00:02:13,309 activity that correlates so we see all these networks in the brain would differ 120 00:02:13,309 --> 00:02:13,319 these networks in the brain would differ 121 00:02:13,319 --> 00:02:14,929 these networks in the brain would differ areas active at the same time and then 122 00:02:14,929 --> 00:02:14,939 areas active at the same time and then 123 00:02:14,939 --> 00:02:16,880 areas active at the same time and then they diminish their activity at the same 124 00:02:16,880 --> 00:02:16,890 they diminish their activity at the same 125 00:02:16,890 --> 00:02:19,699 they diminish their activity at the same time as well how visual hallucinations 126 00:02:19,699 --> 00:02:19,709 time as well how visual hallucinations 127 00:02:19,709 --> 00:02:21,860 time as well how visual hallucinations in the psychedelic state might come 128 00:02:21,860 --> 00:02:21,870 in the psychedelic state might come 129 00:02:21,870 --> 00:02:23,599 in the psychedelic state might come about it could be that in the 130 00:02:23,599 --> 00:02:23,609 about it could be that in the 131 00:02:23,609 --> 00:02:25,910 about it could be that in the psychedelic state what you perceive is 132 00:02:25,910 --> 00:02:25,920 psychedelic state what you perceive is 133 00:02:25,920 --> 00:02:28,520 psychedelic state what you perceive is dependent more on the brain than the 134 00:02:28,520 --> 00:02:28,530 dependent more on the brain than the 135 00:02:28,530 --> 00:02:30,440 dependent more on the brain than the sensory data that's coming in through 136 00:02:30,440 --> 00:02:30,450 sensory data that's coming in through 137 00:02:30,450 --> 00:02:32,929 sensory data that's coming in through the eyes and the ears and we have the 138 00:02:32,929 --> 00:02:32,939 the eyes and the ears and we have the 139 00:02:32,939 --> 00:02:35,679 the eyes and the ears and we have the opportunity now to try to characterize 140 00:02:35,679 --> 00:02:35,689 opportunity now to try to characterize 141 00:02:35,689 --> 00:02:38,539 opportunity now to try to characterize exactly how and why this happens but 142 00:02:38,539 --> 00:02:38,549 exactly how and why this happens but 143 00:02:38,549 --> 00:02:41,720 exactly how and why this happens but what we experience is being real is the 144 00:02:41,720 --> 00:02:41,730 what we experience is being real is the 145 00:02:41,730 --> 00:02:44,000 what we experience is being real is the construction of the brain so when I 146 00:02:44,000 --> 00:02:44,010 construction of the brain so when I 147 00:02:44,010 --> 00:02:45,879 construction of the brain so when I experience a particular color that 148 00:02:45,879 --> 00:02:45,889 experience a particular color that 149 00:02:45,889 --> 00:02:48,740 experience a particular color that doesn't mean that color exists out there 150 00:02:48,740 --> 00:02:48,750 doesn't mean that color exists out there 151 00:02:48,750 --> 00:02:50,599 doesn't mean that color exists out there in the universe that a red mug is 152 00:02:50,599 --> 00:02:50,609 in the universe that a red mug is 153 00:02:50,609 --> 00:02:53,000 in the universe that a red mug is actually painted some color that that 154 00:02:53,000 --> 00:02:53,010 actually painted some color that that 155 00:02:53,010 --> 00:02:55,159 actually painted some color that that exists independently of my mind and 156 00:02:55,159 --> 00:02:55,169 exists independently of my mind and 157 00:02:55,169 --> 00:02:57,039 exists independently of my mind and brain now red is something that my brain 158 00:02:57,039 --> 00:02:57,049 brain now red is something that my brain 159 00:02:57,049 --> 00:03:00,020 brain now red is something that my brain construct in order to interpret visual 160 00:03:00,020 --> 00:03:00,030 construct in order to interpret visual 161 00:03:00,030 --> 00:03:02,059 construct in order to interpret visual information this Lisa the question is 162 00:03:02,059 --> 00:03:02,069 information this Lisa the question is 163 00:03:02,069 --> 00:03:17,790 information this Lisa the question is anything real is anything really there 164 00:03:17,790 --> 00:03:17,800 165 00:03:17,800 --> 00:03:19,860 you