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Brain cells that track location in space appear to also count beats in time (quantamagazine.org)
212 points by jacobwg on May 7, 2018 | hide | past | favorite | 85 comments



If you take enough acid, it can become incredibly difficult to perceive the passage of time with eyes closed. On one of my higher doses, I was in such an uncomfortable state of mental agitation, fetal position under my covers, that I tried killing time by playing a game of pretending hours were passing when I closed my eyes, and I could briefly believe it until an external sound clued me back in.

Changes in spatial perception might also explain some mental visions, like truly massive scale structures that are hard to imagine when sober, but those incidents aren't as profound on acid in my experience, and you don't see them visually. They're more high-definition thoughts.


This all makes so much sense, because I (having never done drugs) have a constellation of perceptual issues which all relate to this. I believe I have a congenital mutation in these kinds of beat-tracking and spatial orienting cells (it runs in my family). My mother (who grew up in the 60s) always says, of the few times she tried these substances, "Why would you take something to feel this way? I can experience these things normally, I wish I could take something to not be like this."

My main thing is with time; in the absence of other people / external factors forcing me to be synchronized, my subjective sense of time is "wibbly wobbly timey wimey stuff". That is, I might subjectively experience a few minutes as if it is a very long time (like the subconscious dimension in Inception) or conversely I might be doing a task and think only a minute passed and it was an hour.

Sometimes when I close my eyes I experience a sense being an ant in a tiny room versus being the size of Galactus in a solar system sized room, and then warping back and forth like looking backwards through a telescope. That is, the relative scaled distances remain the same but the subjective sense of absolute scale starts to oscillate.

I have amazing visualization skills for reasoning about spaces and machines that I'm not inside of, it's like a CAD program in my mind, but I'm fundamentally unable to track my own location in space. If I walk through a building and take two quarter turns, my ability to reason about where I came from and what's what direction folds over itself in on itself like the collapse of that 4D hypercube house in the Heinlein short story.

The connection to tracking beats was already apparent to me from experience: although I enjoy music, I subjectively experience lengthening and shortening in the time signature even on the scale of between beats in an 8 count. I actually had not understood that music had a beat until I went to a Zumba class for a few weeks and said, "OK I have just one question: how does everyone know WHEN to move?" I had to have someone tap my shoulder on every beat, and the multi-sensory experience like that allowed me to understand what the beat in music was and it was like not knowing there was another sense. (Prior to that I had assumed "the beat" meant "every percussion no matter how rapid" and couldn't figure out how people picked certain ones.

Interestingly, through years of various dance practice since then, I have now got to the point where I can keep a beat, most of the time. But, I still don't "hear" the beat. Instead, I experience it as like that half-breath-taking jolt of acceleration you get stepping onto a moving walkway or if you can imagine grabbing a door on an open train. When I catch the beat I feel it that way, and if I get off beat while dancing and need to catch the 1 or 5 I have to stop for a second with an imaginary hand out to catch that train car and be pulled along again.

While learning dance I felt like there was a varying random time delay between my different senses of hearing the music, seeing people move, moving myself, and my own kinestetic sense that I had moved (I have trouble with sensory fusion in general). It was frustrating to the point of literal tears because I wanted to do it but I couldn't get the circuits in my brain "forward the packets through the network" with a non-random latency. However over time it improved & I think it probably improved my other perceptual issues.


This was such a wonderful and interesting read!


It makes me wish HN had a "super-upvote," or something like Reddit gold that flags a post as being more significant or notable than would be expected.


> Sometimes when I close my eyes I experience a sense being an ant in a tiny room versus being the size of Galactus in a solar system sized room, and then warping back and forth like looking backwards through a telescope. That is, the relative scaled distances remain the same but the subjective sense of absolute scale starts to oscillate.

I have long had a feeling like this, like being tiny by simultaneously huge, but never have heard of anyone else who had experienced it, probably for lack of a good description of the phenomenon. Great description.


I've experienced something similar! But for me, it only happens when I'm sick. I can at times almost use it as a precursor that I'm about to be sick. I think it might be called "Alice in Wonderland syndrome".


> “In older language, distances were typically given by time — the days it takes to go from one valley to another — since it was not distance but the number of sunsets that was easy to calculate.”

This makes sense evolutionarily. I imagine that for the primitive man, a concept like time did not make much sense -- position and motion were the important things to track. We were aware of change, but perhaps we did not conceptualize of change occurring within a stratum like time. Were there any reasons we would track the number of sunsets before the advent of agriculture?

I would really like to see some research on why time behaves so strangely on psychedelics. Our everyday consciousness is mostly stable and steady so it's quite natural to think of it as dependent on time, as if there is a constant metronome quietly ticking away in the background. Most people assume that 2018 will feel mostly the same and take about as long as 2017. Only when things start slowing down and we peer behind the curtains of our egos do we get the sense that things are much weirder than we'd like to think.

Personally, I think the illusion of time must involve a many different brain processes. Memory is certainly one of the keys, but I wonder if the overall state of connectivity or speed or processing of the brain doesn't have an effect. The ego also seems implicated somehow, as we experience time differently in states of flow and moments of awe and wonder.


Interestingly, where I'm from (BC, Canada), it's quite common to give distances between cities in terms of driving time.

"Oh, Kelowna is about 5 hours away."

Is this expression common anywhere else?


This is common both in the Southeast US (where I'm from; for example "about an hour up the road from here") and in LA (where I live; for example "like 20 minutes from downtown, 45 with traffic")


I'd say it's probably the most common encoding for casual communication. Nobody remembers distance (unless for specific trips were it was read). 500m ? 1000m ? well "2min that way" + some external location to help ballparking.


I suppose. I've noticed that I often answer questions ostensibly about distance with time units. For instance, I was recently asked by the boss how far do I live from $meeting_place, to which I answered "90 minutes or so". Because what he was really asking for is how difficult it would be for me to get there, for which time is a much better approximation than distance.

Usually people don't care about actual distance. It's not useful for much, unless you're drawing a map. Also, note how new transport options change the perception of the world. 200 years ago, my ancestor would probably not bother with a casual visit to a town 70+ km away. These days, I don't think much of running errands over that distance - it's a 1.5h bus ride away, so I can go there in the morning, do stuff, and come back before dinner (and thanks to the current tech, I can also clock in some work time during commute).


Yes, it's used in Polish (coś jest 2 godziny stąd = something is 2 hours away).

Btw, there's this joke about a soldier asking a sergeant "what is timespace", and the sergeant answers "get a shovel and dig from here till sunset".


Here in Ohio it is common to give distance in time. Especially south/east Ohio in the hills.

There are also congested areas in Col/Cle/Cin where it might take 20min to go three miles so distance is also time there.


I'm from eastern Canada. I'm not sure I've ever heard someone give distance colloquailly except by using time.

I'm sure it has happened occasionally, but I wouldn't know how to process the information. Especially since equal distances can take different times depending on speed limits, etc


Yes I would give the distance in time if I was telling someone which suburb I grew up in. Ex. 30 minutes from downtown or about 45 from the airport.

I would do the same referencing smaller cites or states/locations close by. 6 hours from the gulf or 2 hours from this college.


I've heard this is a Canadian thing -- I also measure pretty much all distances by time. (15 minutes away, 2 hours away, 12 hours away, etc).

This might have been the consequence of switching from imperial measurements to metric in the 70s.


A friend of mine was trekking through a small village in the Amazon rainforest and got chatting to one of the locals. When he said he was from London he was asked "How many days up-stream is that?"


My friend from Houston, TX says it's very common over there. My guess is that it's due to how chaotic the roads are in Houston, so a 5 minute drive versus a 10 minute drive makes a world of a difference.


Also from Houston. Giving distances is almost meaningless in this city 2.8 miles away could be 20 minutes or it could be 3 minutes, so time is really the only accurate measure.


Maybe its a Cascadia thing? I'm just south of you in eastern Washington, and I've always done the same thing.


I don't think we have any proof that time is steady. It may just appear as steady. Much like clock based games way back when. You could speed up or slow down the clock rate and the game would be run the same. Only a external observer out side of the system would be able to detect the change.

Edit. But I guess you were talking about our perception of time.


Oh man, that reminds me of the time I tried to get Operation: Weather Disaster (ah, nostalgia!) running on a "modern" computer (win98 or xp, vs the intended '95 I think). After much foolery with compatibility settings, I finally got it to work, and it played great... until the final boss fight. It ran so impossibly fast that I would have to be one of those reinforcement AIs to actually succeed. Must have been tied to clock speed.


Well, okay, but we can map different cause-and-effect relationships to other ones. Like for example, I can say that so many trillions of energy state transitions in a caesium atom will occur in the time in takes me to walk to the park down the street, or drive across the state I live in, and anyone with a caesium atom can, in principle, replicate that measurement. And you can replace the caesium atom with, for example, a spring and some gears, or literally any other periodic event generator. (I mean, we can get into what "periodic" means, as well, but I'll table it for the sake of brevity, for now.)

And, somewhere in our brain, we probably have just such a periodic event generator, although it's probably a bit flawed in the implementation like most things generated by evolution typically are, but it does the job well enough for us to arrive at a sense of time that very roughly agrees with more rigorously-derived measurement devices.

Ultimately time is a shorthand for cause and effect, and the fact that causes propagate to their effects at roughly the same speed (relative to a reference cause and effect) everywhere we measure them (relativistic effects notwithstanding). If you have evidence this is not the case, I would love to see it, because it implies some new physics. You would win a Nobel prize for this, easily, if you could prove it.


If there is an outside observer with their own sense of time, how would we know which time is real? Are they both? It would seem that, even if not steady to the outside observer, our time is still steady. In a world where physics depends upon time, is it even possible for time to not be steady?


When I was typing that I was thinking the hypothetical observer. I don't think there can actually be one with respect to actual time. But to be able to think about how maybe it does work you have to think as though there was a an ability to observe the universe in such a way.

But you are right, if there was a outside observer the same stands, just for that observers observer -- hypothetically.

> In a world where physics depends upon time, is it even possible for time to not be steady?

I think so. Physics is a construct that we have to describe how our universe works.

Lets think about things in "ticks" where a "tick" is just one particle or I should say interaction happening in our universe. Or better think of our universe as a big state machine. Between each new state there are many ticks arranging the matter and getting ready for the next observed state. And by observed state I mean observed by the universe -- or realized. Now we have two time domains to think about. One, tick time. How long is a tick? Would it matter if some ticks took "longer" than others. Then you have the notion of time outside of a tick, that gives ticks its "tick time" or what makes some ticks "longer" than others. If this is anywhere near the case then time outside of the umbrella of each realized universe state does not matter.

I may not be doing a good job of getting the notion out of my head. But try to think of it if you were in a video game. Lets take it back to maybe the "Max Payne" days given it is a game that has some dealings with time. If you were playing the game on a laptop and closed the lid and the computer suspended would Max be able to detect or care even that the time between rendering one frame the other went from something like 60FPS (well back then 12FPS) to 2 hours our observed time to render the next frame? We would be the hypothetical observer. Max would not have a clue.

Anyways thinking about how time works is always fun. About all we can do is learn how time works from our observable position.


I think the interactions between "ticks" not being "observed" or "realized" by the universe is what gp means when they assert our [physical] world depends on time. If these between-tick interactions are not impacting our physical measurements then I am not sure it's possible for time to not be "steady" from a single frame of reference.

I can of course imagine a scenario where different entities, even in the same universe, experience the passage of time differently. For instance, a positronic robot whose consciousness is only switched on for one minute of every hour. To this being, events could appear to happen willy-nilly, without causation, due to activity between ticks, but the robot would have no way of knowing why the world works like this without talking to another being without the limitations who has been making observations in "real time". So perhaps something like this is happening to us and could explain some weird quantum phenomena, but I'm having trouble thinking of any way we could test it.


I can see that point now. Yes, maybe how our observed physics and universe depends on constant time illusion.

Yes, the problem of how to test such things. That is why it is so fun to think about it.

For all we know between the seconds a trillion trillion tiny life forms that resemble ants slip out between the cracks of space time and take a untold amount of time (to their reference) to nudge each particle just so according to a small tattoo on their forearms. When they are all done they slip away just as mysteriously as they came. And each time they come back to arrange our universe it is done so by ancestors of many generations removed of the last workers who came to enforce our its will on our universe.

This also brings me back to Lawrence Krauss? with the notion of there is not really nothing in nothing and we can't truly ever have a "vacuum" void of all. I think it was in his book Something out of Nothing.


This idea involves mapping one time line to another. Why would you suspect a timeline in which our timeline is embedded? That seems like a more interesting question than the shape of the mapping.


It's Time Turtles all the way down.


Time was always with us and we have organs that regulate with circadian rhythms for example and brain is one of them. There are also processes regulated by daylight, so its fair to say it always mattered even if we didn’t have a reason to measure it


The greatest masters in the history of the human world such as Gautama Buddha never taught or used the term "ego". That ought to tell humans something.


I've developed an intuitive understanding of what people mean by this term after experiencing its absence and subsequent return. It's the judge, the classifier, the model-maker; it filters incoming information and tries to make sense of it, usually distorting it in the process. Without it, the outside world is strange and magical but also chaotic and overwhelming. But that's just a description, the feeling of its presence is something else. I can pinpoint exactly when it starts to work overtime after e.g. a personal attack as it tries to maintain an undisturbed worldview. What would be the closest analog to such a concept/process in Buddhism?


It's not a matter of what it is in Buddhism, the term doesn't refer to an existent thing as it is, THAT is the problem. It's used only by those who don't perceive. Let me give you an example. Think of a mathematician who knows their shit. Now think of that mathematician using an ambiguous term that lacks rigor and therefore introduces inaccuracies in a range of cases. A lay person who doesn't understand the term may use it easily but the mathematician in the other hand finds it very hard to use such a term. The reason is merely that they can realize it's not true.


I don't understand, is the "ego" just an illusion?

Not the one who downvoted you btw. I did read somewhere that Buddhism doesn't have the concept of ego, which genuinely confuses me as there seems to be a very real process occurring in our brains that labels and categorizes information, which introduces distortion and the "ignorance" that leads to delusion and suffering (in the Buddhist view).


Illusion? It depends on the exact range of your definition of the term.

What exists itself is the truth. Who can see it as it is? No one can speak of something they haven't seen as it is.

Every living thing suffers.


No offense, but this wasn't helpful to me. I feel like you're speaking in riddles now. Do you have any sources I could read up on?


I think it means ego is just a label for a thing in the world.

  What exist itself is the truth.
Not the label.

The call for a try to define ego as a precise as possible ("as a mathematician") and in the sibling post from user blueprint probably shall make you attemt just this, but fail at it. I think the "ego" dies when you see what you are looking for in what it is. Not in words not in labels not in labels. Just become aware that your model-maker is trying to model the world that really is there. You are what you are beyond the modeling process.

  What exist itself is the truth
How could you describe it? How could you speak of it? Doing so requires modeling it and therefore it is not the real thing anymore. Therefore you can not really speak about "it" without just referring to a experienced experience.

  No one can speak of something they haven't seen as it is.
Trying to thinking about the "real" world behind and trying to grasp and feel and see it all at once as it is gives me funny tingly feeling in my stomach. But thats is probably not what the they mean.

One fun thing to consider: When there are no models no labels no boundaries no judgements, where does something start and where does it end? Does that even make sense? Objectively the real world is just what it is, one. No things at all. These are just models. The underlying world is still what it is. One.


May I mention to you that I differ from your interpretation?

> Objectively the real world is just what it is, one. No things at all. These are just models. The underlying world is still what it is. One.

What is the answer of 1+1?


Depends, lets say 2.

Math.

Is it access to a real realm of reality or just a bunch of tools to help us make it in the world?

Yea thats a good question. Looks like a question where my answer is probably "both".


I used mathematics as an example to give you a sense of what things in reality (truth) are like. People don't perceive what is in the world of the truth just by learning what exists there from someone who can see and say it. Nevertheless, if you learn and use the truth, such as in your work, you can get what you want. You just won't be able to confirm how much of the whole thing you can see, lacking enlightenment.

By the way, everyone is in reality. So how can you say "access" to a real "realm" of reality?

When you decide you have something to you want to know, ask me again.


I had a short time to reply and wanted to tell you the information you needed. It takes time to confirm. Every living thing suffers means to stop suffering then you have to die forever. Really think Buddha taught that? People don't need a rare master's help to do that lol


> I had a short time to reply and wanted to tell you the information you needed.

I understand, thanks for taking the time to reply in the first place. I apologize if I was curt, but I found your posts here hard to understand. Reading your past comments helped elucidate what you mean.

I'm going to sleep now and I'm finding HN frustrating (I couldn't reply to you when I first saw your post) -- how can I contact you? I'm curious how you came to know what you know and if you had a teacher (your past comments hint that you did). I would like to find a good teacher, but I've been dismayed by my contacts with spiritual people and truth seekers. They are nice people, but they all seemed delusional and I had a bad gut reaction to them. You also seem delusional to some extent: you engage in pedantry and over-rationalization (I also do the latter so I recognize it easily). I do find certain delusions to be useful and engage in them consciously for my and others' benefit. Anyway, I want a teacher because my search has been haphazard and I basically stumbled onto my current elevated awareness (in comparison to my previous self) by sheer luck.

Thanks for posting on HN, even if people don't always want to hear you!


You need to ask lots of questions and we need to keep checking you understand in every detail. That can take a long time. The best situation would be for you to meet an enlightened being and observe what they say and do but unfortunately there are none alive. You would notice that they advise you not to say what you have not confirmed and can help you confirm the difference between your thought that you are aware, and things in reality. This is a very difficult process for 95% of people to undergo and accept. So, if you don't mind, could you tell me first of all what you really want to know? Lots of people said they want teaching but after they get something they want they usually leave and don't come back.

As for delusion when you say that to someone please provide something they can confirm.


The same could be said of the term graphene, transistor, computer, genetics, probability distribution, bayesian, nueron, electricity, and millions of other words. We can't learn much from the lack of their use, because the lack of their use says little about their validity.

https://en.wikipedia.org/wiki/Anachronism

https://en.wikipedia.org/wiki/Presentism_(literary_and_histo...


Are you suggesting categorical equivalence between an unconfirmed concept in psychology (which people use without being able to give its definition) and a confirmed physical effect used in material technology?

Your fallacy is.....


Yes, I'm suggesting an equivalence.

The reason that fallacies exist is because there is underlying structure to arguments. For some arguments, its possible for every statement within the argument to be true, but for the conclusion to be false. The argument which you gave for skepticism toward the concept of ego is one such argument that exhibits structure level weakness. The fallacy label is argument from authority. Often this argument form is used despite it being fallacious, because authorities tend to be authorities for a reason. So using conclusions they derived, despite not sharing the logical backing which led them to their conclusion, can end up providing correct answers. In this case though, in addition to the flaws in argument form, some of the premises the argument is built upon are also untrue. Experts in the past aren't necessarily authorities on their subject matter thousands of years in the future and what someone teaches about doesn't reflect the full sum of their knowledge on a topic.

Seeing this lack of integrity in structure, I set out to provide counterexample which demonstrated the lack of integrity in the argument structure. In that sense, as inputs to the fallacious argument structure, both ego and the terms I gave are alike.

Both the terms I gave and the term ego were inputs to the argument structure, they can be categorized as inputs used in such a way, and they share that category with each other.


Wasn't it Freud only 100 years ago who popularized the modern usage of the word 'ego' as everyone uses it today?


Yes, however, people a long long time ago have used variations of the term. Why do you think deteriorated forms of Buddhism nowadays have attached themselves to the term ego? The term has got a certain characteristic which those who propagate deteriorated truth need to use. They talk about losing your ego for a reason. So, I wonder if you've done this exercise before... have you ever tried to come up with as concrete and rigorous a statement of the definition of the term ego as you can? It doesn't have to be so profound nor complicated. When people lose their ego and don't gain a true ego in replacement it means in real life they lose themselves and die forever. (Buddha taught people to save their own self, remain themselves, and live forever.) Therefore people's usage of the term must be understood to be imprecise and subtextually cover too wide a range. You never hear of a mathematician being fairly called egotistical for insisting it's incorrect to state 1+1 = 1 or 3. Buildings and bridges made by those who believe it can be so will collapse. Then why do we accept this lack of rigor in subjects so important as our mental and spiritual health? Only because we've been compromised by something already. However, many influential people still aren't willing to admit this.


I'm finding your posts intriguing despite disagreeing with you. Do you have any sources for further reading?

> Why do you think deteriorated forms of Buddhism nowadays have attached themselves to the term ego?

Is it deterioration or just accepting new ideas? I don't think that 2000-year-old Buddhism had all the answers, or would even be useful to a Westerner (I do feel that we are mostly exposed to "deteriorated" forms of Buddhism, but maybe it's for the better).


> I don't think that 2000-year-old Buddhism had all the answers

Buddha while alive only gave answers to the level of the questions people at that time were able to bring to him.

No one from modern times asked Buddha about gravity, or electromagnetism, or calculus, or about Bernoulli's principle, nor is he alive in modern times to inform us of what we ourselves can't recognize right in front of ourselves.

However, if, hypothetically, someone were to bring questions about black holes or dark matter to Gautama Buddha, then I feel very confident based on my understanding of philosophy that his reply would be to the effect or meaning of "if you can tell me or point out exactly what X from your question is, concretely, then I will be able to tell you whether it exists or not in reality, by placing that matter upon the formula that operates the world, and checking the result".

> would even be useful to a Westerner (I do feel that we are mostly exposed to "deteriorated" forms of Buddhism, but maybe it's for the better)

What is left is not helpful to us ordinary people for discerning or learning Buddha's teaching. We lost his truth through the process of it being handed down. His teaching is not meditation, four noble truths, eightfold path, nor precepts. It's not that you go to sleep, abandon yourself, stop suffering, and die forever. He taught people what exists, and how it exists, because he knew that was the way to enlighten people. Nevertheless he didn't explain about the steps to achieving enlightenment. First, falsehood must disappear (you must be free of lies). That means you have to open your eyes to the truth. Secondly, you have to be able to see 'what is'. You have to know where right and wrong exist: facts. Third, you need conscience and courage. You wouldn't go to people and teach them through terrible treatment without conscience and courage. Fourth, there must be endless love in yourself to go teach people 'what is' repeatedly. Through the process, you burn up the karma in your consciousness. Anyone who teaches enlightenment can be achieved without agony and love is telling a lie.


"Ego" is a European word so why would Buddha use it? Please try to stay on topic.


I'll be sure to tell all the Buddhists I meet who use the term that you said so.


Buddha lived literally over 2000 years ago. Please go read a book.


In short, time awareness and spatial awareness are linked. Does that mean if you increase your spatial reasoning skills, you could increase the accuracy of your perception of time? I ask because my spatial reasoning skills suck and so does my sense of time. The possibility of increasing both of these skills at the same time instead of just the one changes the cost/benefit equation for me.


Go to a reasonably safe area and practice the following: Stand still, look around, select a target, close your eyes, turn/walk to the target and reach out to touch it. Then open your eyes to see how close you are. To do this well you need to envision your location and movement in your head. I don't know if practicing this or a variant of it will help because you eliminate the visual feedback and rely on the brains "projection" based on dead reckoning. It does not surprise me that doing this well requires an accurate internal tracking of time as well as position because speed determines the rate of change in position.

You may also want to try remote controlled toys - cars, planes, drones. Controlling them well requires that you be able to transform your position into the vehicle. Beginners tend to turn the wrong way when the vehicle is coming toward them.

Now that I think of it, don't walk around at first. Just face away from a door, look around, then shut your eyes and try to turn around and reach for the doorknob. If by chance you make a real experiment of this or find a way to get better at it, please write about it!


I think the question that has to be asked is what is the specific deficiency? What if navigation skill is like a 3 legged stool that needs all 3 legs to work? Different people could be missing a different leg.

For instance in my case I'm actually better at steering an RC car or similar than I am at figuring out which way I should turn myself. To the point that sometimes when I'm lost, trying to relate a map on the wall to hallways in a building, my best strategy is to step outside myself and say, "OK if there were a mouse in a maze which way would the mouse have to turn here?" Often, the answer I get from doing that is different from what my brain tells me I myself should do; always, it is my first-person reasoning which has it wrong and the 3rd-person reasoning which is right.


That has to be one of the most interesting things I've read. I'm going to pay attention to my own navigation skills now as there are some gaps may be similarly odd seeming. There seems to be a distinction between the map/real-world and just navigating the real world without feedback.


I have horrible spatial awareness but I can easily keep a beat and I've been a drummer when I was younger. As with all these correlations they are probably too simplistic.


I'm also a drummer. Rhythm is not the same as the awareness of the passage of time. How are you with the passage of time throughout a day? Do you know when it's morning or afternoon without having to look at a clock? Do you know what day of the month it is without having to look at a calendar? How about month of the year?


I see a lot of child comments using "spatial" to refer to multiple distinct concepts: 1) coordination and movement in space, 2) visuospatial skills (i.e. intuition for 2D and 3D geometry), and 3) navigation. While many tasks make use of multiple of these capabilities simultaneously, there are clear behavioral and neuroanatomical dissociations between them (thought slightly less so between 1 and 2).

Coordination of movement in space (for example something like grasping an object) is more dependent on parietal cortex & the dorsal visual stream (the so-called "where" pathway), and the cerebellum.

"Visuospatial skill", as typified by tasks like mental object rotation, is more ascribable to temporal cortex & the ventral visual stream (the so-called "what" pathway, responsible for object recognition). However, it often requires both ventral and dorsal visual cortex.

Navigation is hippocampus-dependent. However, the hippocampus is not a "GPS". I cannot emphasize this strongly enough. It is a hub for integrating and associating disparate information from across the brain in order to form representations of and the relationships between behaviorally-relevant states. This explains why the hippocampus is also involved in "navigating" abstract state spaces, for example turn-based game states [0] or auditory frequency [1], when they're behaviorally relevant. It gets analogized as a GPS because 1) most of the research involves spatial tasks, so space is the behaviorally-relevant dimension, 2) a certain Nobel Prize winner does not feel the need to update his theory, and 3) "Hippocampus = GPS" is too sexy and intuitive of an analogy, especially for the lay press.

The idea of the hippocampus as an "associative engine" also helps unify its seemingly disparate roles in "navigation" and memory when you consider that a memory is just information from disparate brain areas that's been associated via temporal correlation because of its behavioral relevance. It also explains why researchers observe "place cells" and "time cells" and "head direction cels" and "eye position cells": because these variables are behaviorally relevant (i.e. important for maximizing reward) in the task the animal is performing.

[0] https://onlinelibrary.wiley.com/doi/pdf/10.1002/hipo.22523

[1] https://www.ncbi.nlm.nih.gov/pubmed/28358077


Interesting, have you ever had depression? Depression has been linked to low hippocampus size[0]. Would be interesting to see how the drug mentioned by the article affects spatial reasoning and sense of time.

[0]: https://gizmodo.com/5874433/the-pill-that-could-cure-depress... (I once read about a differently-named drug which increases hippocampus size and treats depression but I'm unable to find it now)


The only time I've ever been "depressed" was when I was also addicted to high reward behaviors. I know these high reward behaviors are linked to both depression and a lack of short and long term memory. It sounds like high reward behaviors (ie: addictions), small hippocampus size, spatial awareness and time awareness could all be interconnected. Or maybe they're separate causes for the same phenomena. I don't know, but it's worth taking a closer look.

I wonder how much it costs to get my brain scanned.


> It sounds like high reward behaviors (ie: addictions), small hippocampus size, spatial awareness and time awareness could all be interconnected. Or maybe they're separate causes for the same phenomena.

Yeah, I suspect these are all deeply related. Fascinating.

> I wonder how much it costs to get my brain scanned.

Sounds like something that could bankrupt you stateside. If you want to get it done cheaply and by qualified people, there's always Eastern Europe :)


I have problems with time and with space. I got into dance and it was hard because "random packet latency" in my senses messed with my ability to learn and keep a beat. However through the help of dance partners tapping out the beat on my shoulder, and years of practice, I was able to reduce that "sensory latency jitter". I can't say for sure if it helped my spatial sense, but now that I look back, it probably did. I have always understood that, for me, the problems were linked, because you cannot do dead reckoning without an accurate clock.


I play drums, the sensitivity increase by detailed perception of time translates very well to kinetic sensitivity (I can almost sense momentum derivative). Not large scale space though. I do think that most of our senses are first tuned for near future and thus local interactions, not architecture-size understanding?


It makes sense that our sense of time and space would be linked - how else does one perceive the discrete passage of time but by sensing discrete spatial differences in our surroundings? The hands of a clock, the position of the sun, the water level of a draining pool, etc..


It's all just pattern matching. I would posit that the same neurons that imagine the future, also assist in imagining areas outside of ones' immediacy. Qualia are related to information sources that are orthogonal/uncorrelated.

Try this experiment and see how you fare. When you're in the shower, imagine that the feeling of the water (preferably cold), is like being in the middle of a fire. Imagine being bathed in the flames. Try to associate "wet" with smoke, dancing flames, no pain in any way. It's surprisingly hard but possible. It almost puts me in a meditative state when I try this unintuitive association excercise.

Anyhow, there are learned separations between observations and qualia. I think the one between time and space is such -- learned, not so much due to actual specialization in the brain's anatomy.

https://en.wikipedia.org/wiki/Phaneron


That seems to follow. Subjectively, meds that boost my visio-spatial skills seem to also help my temporal perception/planning as well.


If they weren't linked, I don't think I'd ever be able to catch a ball thrown up in the air


A point in time is an (n-1)-dimensional slice through an n-dimensional space.


This is a really interesting concept. I'm able to take a look at the layout of a room, then turn off the light and navigate across the room easily without running into obstacles. It's not a perfect skill, but it seems like a very tangible ability to me since I consciously do it. I'm also able to wake myself up most mornings without an alarm within 15 minutes of my intended time despite not having a regular schedule, but since I do that while unconscious, I'm hesitant to believe that it's a real ability and not just good luck. The idea that my brain's ability to count beats in time could be related to my it's ability to track location in space makes me believe it could be a tangible ability after all.


I am not sure what to make of this. My spatial sense is immaculate - I can sense direction/orientation extremely well - I have near-perfect recall of "way to destination" - so much so that after having visited any previously unknown location once, I can navigate back to it years later without much effort.

Time, on the other hand, is a complete mystery to me - I can not tell if a few minutes have passed or hours. I am totally dependent on my clock and calendar to be a functional adult. Similarly, I have no sense of rhythm, beats etc. Nada, zilch, zero.


I can think of loads of reasons that both what the article says and your experience can be true. For instance, maybe your neurons are better at handling spatial information? Nowhere in their findings do they imply that the quality of the space and time tracking has to be the same.


Do your special skills work as well with your eyes closed? It may be that you’re very good at integrating external waypoints and references, and simply lack those for time.


Vision is an important part of my navigational ability, but I can (very rarely) sense location with eyes closed - eg. with eyes closed on a train/airplane being able to guess where I am on the journey (hard to explain, sorry).


That article prompted me to reread "Remembrance of Times East" [1]. That describes an Australian aboriginal tribe which only has absolute position terms, no relative ones. So they say for instance "the cup on the north-east side of the table", rather than left or right.

This even affects their concept of time, whose flow from past to future is described in terms of an absolute geographical orientation frame. Rather than me repeat it here, if you're interested, read the abstract of [1].

[1] http://journals.sagepub.com/doi/abs/10.1177/0956797610386621...


Time is a path “through” space. In other words, change over space IS TIME. That is why they found “timekeeping” in the space brain. In a sense, they didn’t discover anything. They reaffirmed that time is an aspect of space (or of any n-manifold).


Fascinating article. Time is a human construct, it's interesting to me how the fundamentals of the planet - sunrise and sunset, the two solstice moments as the planet tilts into the other direction to provide more of less sunlight - are overshadowed by human habit patterns. The 'Brain’s Space-Time Matrix' sounds like our true underpinnings, as opposed to our concepts of time by the clock and calendar year..


This is a half-formed thought, but if you are blind, how would you perceive space? You can feel against a wall, but you will only be correlating time with locomotion (how long it takes to move your hand against a wall at a certain force) to create space. Spatial reasoning becomes temporal reasoning. (Ignore for the moment you can directionally locate by hearing). It makes this result even more fascinating to me that they are biologically linked to the same part of the brain, rather than one part compensating for another.


Hearing directionality is also temporal, you only know which way a sound is because you know which ear heard it first.


Space is only noise that you can see.


Then sound is space that you can hear.

Both are interesting ways of framing space and the senses, but I'm not sure what you mean by "only". To reduce space to "only noise", in my understanding of your statement, is to imply that it is something extraneous, something to be ignored, or at least given less significance, instead of it being actual, existent, a fundamental aspect of reality that we can describe in useful ways. Either way is interesting imo.


It's a song by a guy named Nicolas Jaar. I didn't mean anything by it, I just thought it sounded cool.


Not only does it sound cool, but it is cool!

https://www.youtube.com/watch?v=m4krz1cTmmU


and thus the space time continuum was born

I find percussions to be highly abstract and mathematical, also probably related to our sense of balance




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