This Present Moment: Philosophy & Neuroscience

We're going to keep doing this, probably accidentally several time and now all the time, but physicists in general would probably say that there is no such thing as now from a universal point of view, that relativity shows us that there isn't simultaneity across the universe, and there's no external objective way to to sort synchronize events into and now in the timeline of the universe right and and similarly, you can't say I'm gonna do x uh eight now's

from right now. It just doesn't work. Yeah, there's no apparent unit of now in in physical time keeping either. But physics aside, we still do have this profound sense of the present. I mean there's a reason these concepts appear in our language. Why do we have a word for now? Why do we have a word for the present if there isn't something relevant going on there? So this time we wanted to explore the philosophy of the present, the philosophy of now, and the psychology and neuroscience of now.

What's going on in our minds when we perceive a present moment, when we think about what's happening right now? You know, I know I've mentioned New age and spiritual author Eckart Tootle on the show before and how I found some of his ideas concerning mindfulness rather helpful. Uh, And what his central thesis is that the present is is all we have and this too, being part of time is an illusion. Oh great, so we've got nothing, Well, you've got, but there's a lot to be had and nothing.

Here's here's a quote from totally. He says, quote time isn't precious at all because it is an illusion. What you perceive as precious is not time. But the one point that is out of time the now. And I really like that the idea that maybe we shouldn't think of now as a point within time, but a point outside of time. Yeah, I kind of like that too. I think it might be easy for, you know, some kind of hard science minded people to think of that as like, oh, that's just new age nonsense, that doesn't

mean anything. I think that kind of does mean something. I mean, think about your experience of time. What do you have the power to act on in your own experience? Like, what point of time do you have the power to do something about. You can't really do anything about the past past, because it's already happened. You can remember it, but you can't change it except in your memory by

distorting it. And don't underestimate the power of that. No, that can happen, but you can't actually change what happened in reality. You can change your memory, but the past is gone. You can't really change the future because it's

not here yet. You don't have access to it. Right, So it's you know, you don't have any power over things that are causally disconnected from you down the chain, And in a weird way, you almost don't really have the power to change the present either, because it's happening. That's right, it's happening right now, at least as you sense it. I mean, to whatever extent there is such a thing as the present in our experience, it's what you're experiencing, not really what you're doing. So where where

do you live? Where does action happen? Where does change take place? Yeah? Is it? To what extent? Is it? Is it a conscious thing? Is it is? It? Is? It's subconscious? Is it a series of subconscious processes that are going on? Are we all as as our friend, uh, Scott Baker who put it, Are we all just slaves to the darkness that comes before and therefore there's no

there's no real choice or or or agency at all. Well, I'd say that I think our Scott Baker and Eckhart total are on exactly the same page here that it's just a question of whether you make it sound positive or make it sound negative. I never thought of that before. Now, wouldn't you kind of agree? Yeah? Yeah, I think there's a valid point. Yeah, Uh, totally is just totally is selling a a more positive vision of what the world

can be, um and uh and Baker baman not. That's not to say that Baker doesn't have some optimistic ideas in mind, but he has a much darker vision of of of reality of course, and this we're already getting into the realm of philosophy, right, and there is a heck of a lot of philosophy of time out there. Oh yes, yes, yeah, I mean the nature of the present moment is it's tied up with our experience of reality.

So it is of course the domain of philosophy. It's one of the most argued about topics in all the philosophy. You have multiple different schools of thought that weigh in on the nature of now and time and the place of time, of now in time, and we could we could podcast until the end of time about just the various approaches to this. Yeah. I would say one reason that philosophy of time is so popular is because it's so closely related to the philosophy of the perception of

free will. Um. This came up actually just a minute ago, and what I was talking about comparing you know, our Scott Baker and Eckartley. In both cases, I think they might be add I don't want to speak too much for totally, but I think in both cases it sounds like they're advocating a universe in which we just kind of accept that we are not necessarily the causal agents ourselves that bring about change. That we have the experience, you know, sort of the sensation of being behind our

own actions. But you can't get behind the behind the actions. You know that that you as you are acting now or a product of things that came before, and though those consequences that came before, we'll have consequences that echo into the future. But you don't necessarily have free will in the classical sense under this understanding of time, because where would the free will take place? What would happen?

What changes in the now? Alright, So so let's just roll through some of the broad categories of philosophy of time and the now, uh, and and again again. Each of these is a topic that we could easily do an entire podcast episode on and and maybe very well returned to in the future. So first up, we have to touch on fatalism. My favorite. This is the notion to him that the future is unavoidable. With enough data, or perhaps a robust enough simulation, you could accurately predict

all future events. What's more, you wouldn't be able to avoid those events. The future is not open, but rit closed in inexorable, and this entails a good bit more

than the present, but we'll see how it all ties in. Shortly, I would say that this point of view and my experience is more popular with physicist than it is with philosophers, because a lot of philosophers, I think, are are caught up in the idea of explaining agency, like they're really trying to find free will and agency and our actions. But you know, physicists just say, well, look at what

the math says. It looks. You know, every indication from our mathematical model of the universe is that past and present and future they're all just part of the same block. And that's a block of the universe that exists. So what how how could you change it? In what sense would you be altering the future? Up next, we have a reductionism with respect to time. So the idea here is that time does not exist independently of the events that occur in time. When we talk about time, we're

talking about temporal relations among things and events. And this was an argument of Aristotle and many others. So where do you think this would fit into our idea of modern physics? It seems like modern physics except for the people who don't believe in time like you know, Julian Barber and all those. Most modern physicists would probably not agree with this, would you say, because spacetime is spacetime? Yeah, yeah,

I would think so. Up next, we have platonism, as in Plato with respect to time, Plato, Newton, and others. They counter reductionism with respect to time. The general ideas there with the idea that time is the independent container in which all else is stored. Okay, so this sounds a little bit more like the spacetime idea, like spacetime could exist without the objects in it. Maybe. Yeah. Now this next one is a doozy and it takes us all the way up to Uh. This is mc taggart's argument,

which he made in his work The Unreality of Time. J. N. E. McTaggart argued that there is no such thing as time. He argued that there are two ways to order time, A series in which we measure everything by its relation to the present, and B series, in which we measure things by the relationship between two moments in time. Each one comes with it share of complications and Nictaggart believes that time containing both A and B series is not real, but other thinkers have come along to accept either A

or B rather than reject time itself. So this is sort of asking the question of whether time actually flows, like, is there such a thing as the present? Is there happening in the universe? And if things really do happen,

that would seem to be the A series, Right. If if there's a present moment moving along through the history of the universe, that that's the A series, and the B series would be that time is just a It's just a measurement between change events, right, So that the subset here people who latch onto A or B A theory is that is that A series is all there is and anything that looks like B is really A. In other words, time passes yet a past a present in the future. This is also referred to as the

tensed view of time. And you have B theory, which this say is B is all there is, anything that looks like A is actually be and time time does not pass the tense less theory of right. You know, we talked about this, and I think maybe we should come back in the future outside of this discussion of the present moment and now to do a whole episode on the idea that time doesn't exist, because I think this is not a majority viewpoint among physicists. You know,

the majority physicists might say nothing actually happens. There is no present moment in the universe, but there is a time in the universe. Right. It's it's such a mind blowing topic that we we do need more time to consider it, and we will come back to it at a future point in time. Right, that's when we'll discuss that there's no such thing as time. Of course, it's all an illusion. But yeah, so hopefully then we can talk about Julian Barber and McTaggart and the others who

agree with them. Alright, So moving along with the sort of broad schools of the philosophy of time, we have a present is um. This is an a theorist approach that states that only the present exists. Things outside of the present. So the claw source of roads, Genghis Khan, or the next Fast and Furious movie does not exist. They just literally are not real until they are currently existing. Right. If it's not currently existing, it's not a thing, be it Genghis Khan or or or a movie that is

inevitable but not yet made. So the only thing that exists is the present moment, and the past and the

future are not real and do not exist. Uh yeah, that seems like it would be hard to make sense of for me, It would be hard to make sense of that picture of the universe given um, given like the lack of simultaneity you know, across the universe and the fact that things can appear out of order to different observers based on the speed of light and all that, right exactly, so, we have another another argument that might

work better with all that, and that is eternalism. This is one of several non presidentism approaches, and it argues that objects from the past and future exist. We can call these non present objects. They exist just as much as present objects. So the Clossus of Roads and Genghis Khan exist just as much as you and I, even if they are no longer present. And here's the other thing, the inevitable next the Fast and the Furious movie is much the same. It's as real as anything that's around

right now or existed in the past. But that's only because it's actually going to happen. It's not like hypothetical future things that never actually happen exist right now. Well, that's the thing, it's ultimately hypothetical because something could occur, or a series of things that could occur that would obviously prevent the next Fast and Furious movie from happening. But in that case it never would have existed to

begin with. Yeah, I mean, I mean, I would say under this model, only the future that actually happens to come to exist exists right now. But of course we never got another Interspace movie, we know when we never got to explore future um miniaturized adventures inside of Martin

short stomach. Oh but we will because Hollywood will continue to be out of ideas for new things, and they will just revisit old franchises until they're plowing into like Police Academy reboots and stuff, and they've got to get to Interspace two before they do the Police Academy reboot. All right, well, I look forward to Interspace too, even if I'm ultimately disappointed at how overwhelming the c g I is. Alright, Beyond this, we have the growing Block

Universe theory of time. This is an anti presidentism approach in which the universe is continually getting bigger because of all this stuff we keep adding. So we're you know, we're front loading time with new time, new stuff, new space time. So every second that exists, we're essentially adding a room onto the house because there's more for the universe to contain since it contains past and present. Okay, and then just a one added note on time travel

that I thought was interesting. So time travel cannot happen in an eighth theory theorist president is um because the present is all their is, so you can't travel into the future of the past. Uh. And of course you know, in addition to all the backward this is an addition to all the backward causation is impossible talk, which is all fruit for another discussion. Yeah, well, I think backward time travel is also impossible under b theory, right. Yeah, well, I mean I would say that that that is my

understanding as well. But we're really overdue too for a proper time travel discussion on this show. Yeah, well, I think we should take a quick break and when we come back, we will start to look at the psychology and neuroscience of our experience of now, what what happens to the mind on the present moment? Thank alright, we're back. So in our previous episode, we talked a little bit about mental time travel uh in memory and how these

are core to our experience of time as flowing. We remember what has come before, we anticipate and use mental time travel or chronasthesia to understand what is going to happen.

And then we have to wonder what what what would it be like to be un shackled from these I mean that's kind of cord to a lot of meditative exercises or even the flow states that we get into with our our work or our hobbies, like what what can we do to cut off the default mode network and no longer worry about the past and the future

and live in the quote unquote present. Well, some answers to this question can be found in an individual known to psychologists as Patient K. This is a Toronto resident who suffered severe brain damage during a motorcycle accident, and he lost his episodic memory. So it's important to note here he can still do all the things he learned

to do prior to the accident thanks to his procedural memory. Right, so, if you lose your ability to make memories, you still probably remember how to tie your shoes, right, you can't remember what you had for breakfast? Right. So this guy can speak, he can play games that he learned previously, He can navigate his his neighborhood without becoming lost. But he cannot remember what he did yesterday, and he cannot acculate on what he's going to do tomorrow. He has

no autobiographical memory at all. Now, that second thing you said is fascinating. So his ability to make memories is compromised. And it's not just that now he can't remember what he had for breakfast, can't remember, you know, what he did yesterday. He also can't imagine what tomorrow will be like. That's fascinating to me because it means, in some sense, our ability to remember the past is necessary for our ability to imagine the future. That forward and backward time

travel are inextricably linked. Yeah, and now something's pointed out about this patient by Dan Falk and his book In Search of Time, The History, Physics and Philosophy of Time. He says that patient Casey is quote completely rooted in the present, with no ability to move backwards for forward

cognitively in time. And here's the thing too, He's completely unaware of his condition because he has no no memory, he cannot form new memories of explanations of what's going on here, and uh Daniel Shackter, who who wrote the silent to seven Sins of Memory, which we've referenced on the show before he had He has said that the patient Casey is quote, a shell of a person, a fragment, but also notes that Casey rates his own personal happiness at a level of four out of five, so he's

he's he's quite happy, He's not in a state of misery. And you have to, you know, ask to what to what degree is he happy because he's unshackled from worrying about the future and contemplating the future or remembering anything in the past. Yeah, I mean that it's sort of like asking like, would you like to be like that?

I mean, I think most people probably wouldn't, because you would still feel that many opportunities for things that you deeply care about in life are would be closed off to you if you had this condition, even though the having the condition might not be all that unpleasant in the moment. Yeah, I mean, it comes down to that description of a shell of a person. Would you like to be a shell of a person who's tremendously happy

all the time? Four out of five, tremendously happy. I mean, well, I don't know what would you rate yourself, Robert, Uh, you know what out of well? It vary, you know, it varies from moment to moment. I guess I would say four out of five because I wouldn't want to say five out of five. That's that doesn't leave me any room for improvement. You could always be happier. Yeah, But I you know, I I hesitated to give myself

a three. It's a complex question, you know. I hate to answer well being questions in relation to coffee because it's such a cliche. But I know mine is in relation to coffee. It's like when I when I have had a little bit of coffee, I'm a four. But when I've had, you know, two cups of coffee, I'm a two. Oh, because you get you get too jittery, and I get that, I get the fear. Yeah, it's bad. I have I have noticed that with my own caffeine consumption,

that the rate is a little different now. In his book book, Falk also references another individual, a San Diego resident named ep and he has nearly a nearly identical condition to patient Casey and Likewise, he has described as being quote happy all the time, I'm quote and devoid of a stream of consciousness. He is trapped into present without the ability to traverse either recorded memory or simulated future.

So this seems to show the same thing that he his inability to think about events in the past also prevents him from mentally exploring future events. Um, and I know I've seen at some point there was a case where one of these patients was being asked, uh, what will you do tomorrow? And his answer was whatever is most beneficial. That's that's that's revealing, like in a way, he's he's more honest about the He's more honest in

his answer because he's he cannot engage in mental time travel. Right. Well, if I ask you what you're gonna do tomorrow, you're gonna kind of bluff a little bit, right, You're gonna say, well, I'm gonna I think what I'm gonna do is I'm gonna get up and do my normal stuff, do yoga, have breakfast, whatever. You're kind of bluffing. You can't really know that's what you're gonna do. You just think that's probably what you're gonna do. Right, It's it's ultimately my answer.

It's gonna be just as inevitable as the next Fast and Furious movie, you know. Um, But obviously many different things could occur to to drive both of these trains off the track. I guess the true answer would be I'm gonna do whatever I do. Yeah. Uh, you know I mentioned uh Eckartola already. I'm gonna come back to him one last time in this episode because there's a wonderful children's book that he put out with Mutt's cartoonist

Patrick McDonald, titled Guardians of Being. And it looks at our pets, cats and dogs in particular, and it looks at them as windows into the formless, into the timeless, the idea that that creatures are bound by neither past nor present. And this enables us to better center ourselves

in the present. Uh and and and and you actually reference this a little bit, uh in the first episode talking about when you when you see the excitement that your dog has for a walk, right, Well, yeah, yeah, I mean there's there's like nothing happier in the entire universe than Charlie about to go outside into the grass. And uh, and you get the sense I mean probably probably this is projection, but at least you get the feeling that this is because it's all there is to

him right now. The only thing in the universe to him is the thing he's excited about doing, and it's he's seen all the signals it's about to happen. Like, he's not worried about anything else. There's nothing else beyond that thing. There's nothing really behind him. Is just all about what's about to happen. Yeah, he is. He is devoid or free from the very human concerns of time. And indeed this has been a long a long time understanding of animals that they neither remember the past nor

contemplate the future in a truly meaningful human fashion. Now, I think that that's a little bit complicated by some observations of people like, for example, friends of All who we talk to on the show before um who you know. He's a primatologist. He studies apes primarily, but he talks a lot about the intelligence of animals and signs that he thinks he sees elements of rudimentary time travel in in some of the great apes and in some birds

and stuff. Right, well, yeah, it does get complimental time travel. Yeah, I think not actual time. The morlocks did try and and steal the machine, as I recall. But yeah, if Falk gets into this a bit in his book, he he makes a point that that no ape has ever communicated with sign language anything to suggest he was remembering a past event. Of course, these sign language by apes as a way of develving into their mind is also

a complicated situation. Uh. And and there have been studies with various animals and some birds, uh, mainly primates and birds that have that have allowed scientists to argue in favor of mental time travel. But the the argument against that is, well, to what extent are the do these anticipations fail to go beyond the context of the present? So like are they are they is using a tool

to get a meal out of a log? Are you actually engaging in in mental time travel or are you just applying a certain uh you know, certain cleverness to the the situation or is there any difference between the two. I don't know. I mean, I would say in the case of apes, I think there are some examples. I hope I'm not remembering this wrong, but I think I remember some examples of apes, for example, saving tools for later that they don't need for a task right now,

but they know can be useful in the future. Or for example, I think it was Jay's right, Jay's remembering where items had been placed in a room even though they couldn't immediately access them. Yeah, these are scrub jays, I believe, right. Yeah, those those come up in experiments a lot. So this remains kind of an open question. There are some some fascinating arguments to be made on

both sides. Uh. As far as humans go, however, human infants do seem to live in an eternal presence up until around eight months of age or so, and then key abilities begin to come online more between three and five and a six year old child is is just light years ahead of the smartest chimp or or j that has ever lived. And uh and this is this is a fascinating two. Between eight and ten years old, that's where begin when we begin to see time as

an abstraction. Uh. And another great fact that I ran across in false book is that most ten year olds think they age an hour when the clock turns ahead for daylight savings, but most fifteen year old realize that that's not the case. I'm kind of surprised about that with ten year olds. I would think generally ten year olds would know that, like, the clocks don't determine how

old you are. Well, I wonder how much of the two is just they're not thinking about that kind of thing, and if you just spring it on them, they might say, Oh, well, I guess I am the clocks. The clock when ahead an hour or so, I'm an hour ahead to Yeah.

But but I found I found that in righted this idea that we don't have it now, we don't have a presence, and then our understanding of time just kind of begins to grow and swell until we can truly begin to understand the abstraction and just mind rending complexity of time. All right, well, I think it's time to turn to some psychology and neuroscience experiments to try to understand a little bit more about what's going on in

the brain. We've established that physics probably doesn't really allow for a now, or at least doesn't allow for any kind of universal simultaneity. There's no externally objective now whether or not things actually happen, or whether or not time actually flows in the universe. That's maybe up for debate, but there's not a universal now, and we still have

this experience of now. So what's going on in the brain when we have a feeling of the present, when we say something is happening now, how does the brain decide what now is? I want to look at a series of experiments and thoughts associated with the neuroscientist David Eagleman and many researchers working with Eagleman in his lab. They've done some really cool stuff with the perception of simultaneity in the brain. And the first case I want

to look at is the idea of the flash lag experiments. Now, Robert, have you ever seen these demonstrated or had you know? Just let this work on your mind a little bit. I don't think I've actually observed footage of one of these experiments now, I've only read about them. They're more They sound very simple when you describe them, but when you actually notice it happening to you, it's a little bit troubling. So there are a lot of video demonstrations online.

If you want to see it for yourself, you can go look up a video of a flash lag experiment. But I think I can describe it pretty simply here's one version. Imagine there's a room and in the middle of the room there's a big vertical hoop, and there is also a little light that flat that can flash somewhere in the room. And you see somebody standing at one end of the room throwing a ball through the air.

And while the ball is in the air, there's a flash in the video and video of this room, and you watch it over and over again, Throw flash, throw flash. And what it looks like to you is that every time the flash happens uh somewhere in the air after the ball is about a foot or so past the hoop. But when the video gets slowed down frame by frame, you can see clearly that the flash happens at the exact same time the ball passes through the hoop. And

your brain is getting it wrong. Your brain is lagging behind events in registering when it sees the flash. So you might not think this is all that weird, but it's weirder than it sounds. You're probably thinking, Okay, yeah, Well, it takes the brain a fraction of a second to see things like there's a delay between external reality. Um, and the light has to hit my eyes, my mind has to process it. But it's weirder than that because it's not just that you're seeing the entire world or

the whole video at a delay. You're seeing one part of the video at a delay relative to a different part of the same video. You're you're perceiving events out of order, so the flash is lagged relative to the motion of the ball. It's not just that we don't see things exactly when they happen. We don't necessarily see things in the order they happen. And again, this is this is seeing and perceiving, not remembering, right, Yeah, this is seeing and perceiving right there in the moment um.

So this effect, and you can show this with all kinds of different things. Like another version of this would be you've got a square moving around on a screen, and when it passes a certain point on the screen, another square flashes up on the screen for a second, and you'll be asked to judge the relative positions of the squares, and you might say, well, the square that flashes up is I don't know, you know, three or four grid squares behind the moving square, But in fact

they're exactly in the same place. Like the square that flashes up flashes up when the other. When the moving square is exactly in line with it, but you see it flashing up behind the moving square. Why is this? Why would your brain be lagging one type of perspective perception with with relation to the other. This effect has been known about for at least sixty years. There were experiments with it in the nineteen fifties and there have

been a bunch of experiments on it since. And before Eagleman's team first had this paper about this in the year two thousand, there were two major explanations that have been hypothesized. One was known as the latent se difference, and this proposes that the brain processes moving objects faster than it processes flashed objects. And this assumes quote online model of visual perception, which essentially means that you are conscious of perceiving something as soon as the brain can

get the data ready for you. It's all just coming in as fast as you can see it, and if it takes longer to get one kind of data ready, then you just perceive that thing later. You can think of this sort of like a TV camera that's supplying a live feed or a live stream, but the feed is a little bit glitchy, and some types of things show up on the screen and get pixelated out. It's

basically live, but sometimes things get messed up. The other main explanation before their paper was motion extrapolation, and this basically says that perception is predictive. When your brain perceives a moving object, it compensates for a processing latency by making you see the object ahead of where it actually is in its trajectory. So under this model, when you like see an eagle diving after a rabbit, your brain actively moves the eagle ahead and its dive to make

up for the processing lag. So it's really about ten feet from the ground, but your brain says, well, it's moving pretty fast. Let's make it look like it's seven feet from the ground to compensate. And then this is the basic prince of bowl of of of hunting. Right, you think you're going to aim for where the prey

will be as opposed to where the prey is. Yeah, but notice in hunting you actually have to aim ahead of where you see, so your brain isn't fully aiming ahead for you, like you have to use your hands and stuff to do that. You can't just aim at exactly where you see, because that's not actually ahead of the animal enough to to hit it with the arrow

or whatever. So this version would be kind of like a live feed, but updated with predictive models of things that haven't yet taken place in front of the camera. It would be a predictive, anticipatory camera that says, Okay, you know this person is moving towards stage left. We'll just put them a few frames ahead to make up

for the fact that the camera is a little slow. Wow, I mean it's it sounds like a system that is in place for a brain that is not not employing a lot of like conscious thought about the position of the target. Yeah, yeah, exactly. And I think that's a really interesting idea. But you can, in iediately see some reasons for doubting this, and I'll bring up a big one in a minute. All right, we're gonna take a quick break, and when we come back, we'll have more

on the science of now and we're back. So in their two thousand paper, Eagleman and said Snowski proposed an alternative explanation. It's not either of those. They call their explanation postdiction quote. Visual awareness is neither predictive nor online, but instead postdictive. And this means that when you perceive the flash, happening is retroactively determined by stuff that happens in a period of time after you see it. I'll explain why in a second, but they come up with

a period of about eighty milliseconds following the flash. So in other words, then now you perceive is not a predictive model of the future like the motion extrapolation hypothesis, And it's not a slightly glitchy live feed like the latency difference hypothesis. It's more like a movie. It's more like a pre taped, edited film home patched together by your brain, and it happens really fast. It was a film that was only filmed about eighty milliseconds ago. But

it's not a live feed. It's an edited product. It kind of it kind of plays into, you know, ideas of our of our brain, or at least our perception as being like the pilot in a cockpit, you know, and uh, and we're given the information we need to know about what the crew is doing. We're not actually piloting the starship, but we're just kind of the the

head observer. Yeah, I mean there's a lot in neuroscience that can kind of create that impression, though that also gives a rise to the homunculous fallacy inside the brain. Um But I want to mention a couple of experiments that they used to back up this hypothesis of postdiction. So the first experiment tested the motion extrapolation theory and

they found it to be wrong. So the way this works is you've got a ring going counterclockwise around a screen, and once it hits a certain spot on the screen, the screen flashes up an image of a white disk, and then the ring does one of three things. It either stops right when the white disc appears, or it continues along its original path, or it reverses direction and

heads back to the top of the screen. And they said, to quote what participants report to have seen at the time of the flash depends on the events after the flash. So if the ring stops moving right at the time of the flash, there's no flash lag effect at all. If our brains were predicting the motion of the ring, we would probably see a flash lag effect even though the ring stops moving when the when the disc flashes up.

And then they did another experiment experiment to which further tested the motion extrapolation theory by having the moving ring start with the flash, so that the white disk flashes up as soon as the ring starts moving. The flash lag effect still showed up even though there was no original trajector read to predict from. So this seems to, in my view, pretty much bust the motion prediction theory. If there's no original trajectory, how could you be predicting right?

So instead, what this seems to indicate is that AFT is something that happens after we see a flash of something determines how we integrate the information of the flash. And this is consistent with other findings in psychology and neuroscience, for example, that this is really weird one the color fi effect. Robert, have you ever witnessed this one personally? I don't think I have. Okay, so very simple set up.

In fact, it's it's so simple it'll sound like it couldn't be disturbing to you yet again, but it probably should be. So there's a screen that flashes two dots, that's all. Dot one appears, then disappears, then Dot two appears, then disappears. Weirdly enough, under the right conditions, like if it's happening fast enough, instead of seeing what really happens, Dot one appears, then disappears, Dot two appears, then disappears. In said, we perceive a dot moving back and forth

between the positions of the two dots. This is the plane fi effect. It's the tendency of the brain to interpret a series of still images as continuous motion. And

of course we we know that this is crucial in film, right. Yeah, well, I mean this really makes sense when you when you think about it, right, because we have evolved to perceive the movement of generally physical objects like a mouse running across the ground, and then the mouse is not going to teleport, and therefore, when you have a dot of light seem to teleport from one spot to another, our brain is interpreting that as movement from one spot to another.

I think that's a very good explanation. I mean, yeah, there's no reason to expect we'd see teleportation in nature, and if we see something that looks like teleportation, it would make the most sense for the brain to adapt

to that as if it were an error. This This reminds me too that there have been experiments with very young children that demonstrate uh that they know that teleportation has not possible if they see something like teleportation presented to them, that they know that it's b S. That's cool. Here's where it gets even weirder. So that's just the five effects. That's pretty normal, and we can see the normal explanation for that. It gets weirder when you add

colors to the dots. So it's exact same setup. Dot one appears than disappears, Dot two appears than disappears, but make the dots different colors. Dot one is red, dot two is blue. What people claim to perceive usually in this experiment is not only a single dot moving between the two positions, but changing colors halfway along. So dot one is red, dot two is blue, and you see it moving to the dot to position and becoming blue

about halfway there. Now, it would seem like this would only be possible if the brain were retroactively changing the contents of your present time perception, because if your if your brain is being pre addictive, if it's thinking ahead, there would be no way for the brain to predict the color of the second dot right because you haven't seen it yet. So the only way you could have. This illusion is if your brain is retroactively telling you

what you're seeing right now. There you go. There, there's your now. So the now isn't is starting to look not so much like a now, The now is starting to look like a then. So earlier we mentioned that all this happens to within an eighty millisecond window after an event. What's the deal with the eighty milliseconds? Well, in the next couple of experiments, Eagleman and said Snowski

tried to test the latency difference hypothesis. So they put a came up with a setup similar to the previous experiments. A ring goes around a screen, A white disk flashes in the rings path, and then verily, very shortly after that, the direction of the ring reverses. And essentially they wanted to see how long the ring had to keep going in the same direction as it's a original trajectory to produce the same flash lag effect from the earlier experiments.

If it was just that flashes take a little bit longer to process than movement, allow the latency difference hypothesis. They figured that changing the direction of the ring more than you know, uh ten or twenty milliseconds after the flash shouldn't change the flash lag impression. Instead, they found that it did and it lessened it. So any reversal of the direction of the moving object and before twenty

six milliseconds completely canceled the illusory displacement. And they found that sixty seven to eighty milliseconds of movement in the same direction as the original movement are needed to cause the full flash lag effect. And so their conclusion is that the flash quote resets motion integration, and motion is newly calculated and postdicted to the time of the flash. So what they're saying there their experiments show here is that flashes get processed a little bit different ly in

the brain than motion does. And when we see a flashed object, the brain recalculates what we've just seen and presents it to us. So the first time we're seeing something, it has already been edited in post kind of a weird thing to imagine, Like, what does this mean for us? I would say that in some cases for visual processing, there is a lag window about eighty milliseconds in which our brains are still constructing the sense of now, now isn't happening? Now? Now is happening? At a delay, and

you're not even getting the full story. So from this, I wonder if it could reasonably said be said that the human now is not a moment in reality, but first of all, a perceptual impression. It's sort of a sketch edited together by the brain, not necessarily reflecting the order in which events occurred, as might be measured by a camera or a machine, reflecting an information gathering period of roughly eighty milliseconds, and with variable editing, editing a

facts depending on what happened during those eighty milliseconds. And this brings us, I mean, it just brings us back to the the idea of the cave. Right, we're just watching the silhouettes on the wall. But the way I put it is this, we already know that our memories are not perfect copies of events as they took place. Right. We've talked about this on the show lots of times. Our memories are very low resolution, very suggestible. We tend to change our memories without realizing it all the time.

You just memory is not that good for lots of kinds of things. But what this suggests is even the first time you see something, it is in a way already like a memory. It's as if there is no such thing as seeing in the real time. Even when you think you're seeing something right now, it is already a kind of a constructed memory. Yeah, so many analogies I'm tempted to like to run to to explain this. Uh, they all have to They all hinge on the idea that what we were seeing we're really see you know.

It's like the one that came to mind was, it's like if we're all going through life seeing through a periscope, you know, and so we're not really seeing out of our eyes, you know. Yeah, i'd have to be like a computerized periscope. It's like making some editing decisions about

what passes through and stuff like that. Um, I mean, this would I think cause us to to be a little more cautious about even like, even if you're aware that you should be conscious of the fallibility of your own memory, and you know, if you were going to testify in a court case, you shouldn't be like, you know, I'm absolutely sure that what happened here is you know, X, Y, and Z, because your memory is a little bit more

fallible than you think it is. Probably, But even your perception of events you just now saw just a second ago is maybe a little more accurate maybe, but still could have flaws in it. Even though you think you just saw something, it's not necessarily how it was, especially if it happened fast. Legal experts will have to chime in and let us know if if this has actually been used, because we know that the foulibility of memory

has come up in trial cases before. But but I wonder if anyone has just brought up, as has brought up, just how fallible even first impressions may be. I mean, I wonder by the time you get into a chord, it's always going to be a memory. But this might apply to like, say, uh, impressions from the moment, like if you immediately if you saw something and then immediately wrote down what you saw or told somebody else what you saw right then, Um, that that could maybe apply

to that. Yeah, there's a place where things get even weirder. In a two thousand six paper published in Neurons, Stetson, Qui, Montague, and Eagleman found that you could actually manipulate this effect, the flash lag effect, to cause people to question their own causal role in real time actions. Here's how it went down. So the team had research subjects press a key to make a light flash. Pretty pretty simple, right, you press the key, the light comes up, But the

light didn't flash immediately. There's a time lag between the key press and the flash. And because we're so adaptable and so crafty and and and such great little critters, our brains just started to say, Okay, we've noticed that there's a lag every time between when you press the key and the light comes up, so we're just going to start to ignore that. People started to perceive that the light was flashing as soon as the button was pressed.

Then the researchers did the really devious thing. They cut out the delay after this adaptation period had taken place. And what did the subjects perceive then, Well, because of their adapted perception, sort of updating the speed of the flash perception, some of them started to think the light

was flashing before they pressed the key. You know, I feel like I almost felt this effect when my work computer was updated most recently, because it got to where it was so slow, and it was there's a certain amount of lag time opening programs and sometimes even even typing, especially in a browser. And then everything was suddenly so fast. It was almost as if the words were appearing on

the screen before I tied them, almost but not quite. Yeah, well, I mean one has to wonder that what would you start to feel if you genuinely believed that it was possible that the words were appearing on the screen before you typed them. Well, actually, that's you know what, I guess. I tend not I'd tend not to think of it in these terms. But when one enters a like a real flow state of writing, it's it's almost like that.

And I can and certainly there have been writers before who claim a sort of uh, you know, muse inspiration or something, or the idea that something is writing through them. And I could see where where where it would where that situation would lend itself to such an interpretation. Right, You're probably never genuinely confused about what the words where the words are coming from. But if you work hape a bowl of being genuinely confused about that, that could

lead to really interesting states of mind. And so there's a good New Yorker piece from two thousand eleven about Eagleman actually, and it discusses his hypothesis at the time that this very phenomenon could be one of the causes of auditory hallucinations in people with schizophrenia. Uh So this came to light when Eagleman discovered that people with schizophrenia tended to be very inaccurate on these types of timing tests.

And so, to quote from the article quote, the voices in their heads he suspected were no different from anyone else's internal monologues. Their brains just processed them a little out of sequence so that the thoughts seemed to belong to someone else. And then a quote from Eagleman, all it takes is this tiny tweak in the brain, this tiny change in perception, and what you see as real isn't real to anyone else. So, yeah, I mean that's

a fascinating question. Could schizophrenia or any kind of hallucinatory condition possibly becaused not by uh, you know, not by all the normal mechanisms, but by malfunctions in our constructed sense of now? Is your is your feeling of now, your period of now causation with relationship to the rest of time and the universe, crucial for your sense of

agency and self. Yeah, and you can easily imagine too, like the the feeling of that you did something before you could consciously decide to do it, and what that would do to your you know, it doesn't take take much of a supernatural worldview lane over that to create you know, all matter of demons, and because we now know from Eagleman's experiments, if they are you know, if the interpretation of them is correct, that your sense of what's happening in the moment right now is that is postdicted,

is reconstructed over a very short period of the past, then you can very well see that happening like you do actually to decide to do something, but eighty milliseconds later you have of the impression that you did not decide to do it, that it just happened. On the plus side, if there's anything to this hypothesis, and I don't know how widely this would be taken seriously by you know, psychiatrists in the field, they might say, you know, there are a lot of reasons not to agree with that.

But if there's anything to the schizophrenia hypothesis, I think one positive takeaway could be that timing conditioning therapies could possibly have success in giving people with these kind of conditions relief from some of their symptoms. One last thing about the experience of now from Eagleman's research. Uh, there's that classic adage. You know that if you were spending a minute with your favorite friend or something, the time

passes so fast. But then when your hand, when your hand is caught in a hot wolf trap, time passes very slowly. Eagleman did not find evidence that the duration of perception actually changes in the moment, but he did find evidence that the duration of certain types of experiences did change upon recollection. So the length of now varies drastically when you're remembering events in your episodic memory. Uh. And he thinks this depends largely on the salient novelty

of events we experience. So, for example, a simple experiment, if you show somebody a flashing pattern on a screen, any initial change in the pattern gets remembered as lasting longer than the repeated iterations of a familiar pattern. So take that very simple example and apply that to your life. I think you might immediately see that, oh yeah, that

does kind of happen. Like even if all events last the same amount of time in the moment when they're measured objectively, instances that introduce novelty to your consciousness tend to get stretched out in your memory. Retrospectively, this would mean we could kind of extend our lives by filling them with change and novelty. Yeah, I mean, this is the reason one should travel, one should go on vacations. One should try new things, even even if you're not

actually try having to do them. You know, go go try mini golf if you've never tried mini golf, because it seems to stretch your your experience of life out out even further. Well, I mean I noticed this with um respect to like, uh, reading and watching movies and so just any kind of media. Like if I'm re experiencing something familiar, that experience kind of disappears in the

memory hole, you know. But when I'm experiencing something new in media, watching a new movie for the first time, reading a new book for the first time, I'm uh, that experience gets expanded in memory, like it fills up more time. It seems like my life was lasting longer in the moment. This is why one should also go out of their way to see experimental films that are both novel and boring, because the combined energy, like you'll

remember that experience for the rest of your life. It was only it was only a two hour him about a person setting in a room, but it felt so much longer. Yeah, so I like this. If so, here's one of the takeaways about the experience of the present and now. If you want, if if you're Roy Batty and you want to have more life, always try something new. Yeah. That was Roy's problem, is that all he did was saying, is that you know, he had to turn to violence.

He should have turned to art and travel. I guess he did turn to travel a little bit. He's seen that most of us, uh, you know, wouldn't believe, but you'd think that all those those sea beams glittering in the in the starlight or whatever, that would have He sure did talk about it a lot. Yeah, you know, so it made an impression. Yeah, you know, it reminds me of I came across this quote recently, um by Staring Carcer Guard that, uh he said life must be

lived forward, but can only be understood backward. And I think maybe that's the same way with the present, right, Like you can't really catch the present, you can't catch the present in in a backward looking way. You can only sort of open, have an openness to experiencing the present going forward. That's the only way to do it in the moment. But the only way you can really understand the significance of the moments, the little present now

is in your life is looking back on them with memory. Alright, Well, on that note, we're gonna wrap it up. But again, there there's so much that came up in this two part discussion of now and time. Uh, so much that we we can and should revisit in future episodes. So obviously let us know about any particular points of diversion that you would you would like us to return to in the meantime. Check out our homepage that's Stuff to Blow your Mind dot com. That's where we'll find all

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