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To Pay Attention, the Brain Uses Filters, Not a Spotlight (quantamagazine.org)
285 points by theafh 29 days ago | hide | past | web | favorite | 92 comments

"If the doors of perception were cleansed every thing would appear to man as it is: Infinite. For man has closed himself up, till he sees all things thro' narrow chinks of his cavern."

Aldous Huxley had a similar intuition in his essay, The Doors of Perception: the body perceives everything, and environment (including culture, traditions etc.) teaches the man to close some doors lest he be overwhelmed. Mescaline and other entheogens are a way to open most of the doors. Artists (such as Van Gogh) are people with a different set of doors open/closed.

If we're posting relevant quotes, Lovecraft is a favourite: “The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far."

The sciences, each straining in its own direction, have hitherto harmed us little; but some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the deadly light into the peace and safety of a new dark age.

^^ this part is what piques me because we are finally combining our knowledge from disparate fields and the indicators are truly that it's much more insidious than anyone can possibly imagine so the red pill blue pill moment is upon us as a humanity

> combining our knowledge from disparate fields and the indicators are truly that it's much more insidious than anyone can possibly imagine

What are you specifically referring to here? QM?

The Internet and the www?

It's given humanity somewhat of a global consciousness, but not everything that comes out of that is benign or benevolent.

It's turning into the abyss that gazes back at us --

In general! We're applying all sorts of ideas across various fields. Genetic algorithms, artificial intelligence. Mathematical approximations of processes -- applications to societal control. - everywhere you look knowledge is accelerating and it's either going to lead to new enlightenment or a new dark age

I like to think it's especially applicable to the modern age. The industrial age spelled doom of the environment and climate, and the (dis)information age executed it through the power of greed.

We pieced together all the disassociated information required for our own destruction... and the best part? It was totally and insidiously inevitable.

The man died knowing nothing about the impact his work would have on the collective consciousness http://www.hplovecraft.com/writings/texts/fiction/cc.aspx

I learned of a theory that sacred geometry—often seen after ingesting psychedelics—is simply the ‘signal noise’ within our own brain.

The removal of filters allows us to see this noise and would explain why these patterns are so commonly seen during psychedelic trips.

Scott Alexander has been thinking about this sort of thing recently:



Both are very interesting reads about perception, hallucination, and mental illness.

I strongly recommend reading that essay, it is wonderful

For what (little) it is worth, for a layman such as me it sounds like it make a lot of sense in hindsight.

As the common saying "Tuning out the noise" indicates, focusing on something feels more like dropping irrelevant info in the background than about magnifying the interesting bits.

Also, it seems to make sense to expect important functions for survival to be found in the "ancient" parts of the brain. And the attention capacity seems like a rather important function for survival.

On another topic, I wonder how this finding could serve as an inspiration in regard to the current trend of attention mechanisms in Artificial Neural Networks. The analogy with transformers is obvious, but the part about "blinking spotlights" made me wonder if Nature isn't hiding a nifty trick here.

Which is why some psychedelic drugs are too much for people because it disables the filters for a period of time. You weren't aware of the pressure of your socks on your feet until reading sentence.

Especially psilocybin. "Hero" or "ego-death" doses are fascinating. Filters/barriers break down. Each room in my house had a special vibration/energy based on how I spent my time there. Artwork had deep meanings not previously noticed. Projected families and friends onto chairs in my empty dining room and had conversations with them (with cussing & sobbing). Started to think about my ancestors and had "past life" schizophrenic experiences based on memories and impressions of history. Felt powerful daemonic energy, radiating from body out of my hands, and felt amazed by the incredible ability humans have to create & destroy.

THC/cannabis is too much of a recreational drug... though it's useful for taking the edge off at the end of a psilocybin trip.

Not to take anything away from your experience, but I've noticed that in reading reports from various people taking larger trips, I get this impression that a big part of the experience is indistinguishable from schizophrenia. What I mean is nobody can properly define their terms in any commonly shared way, people believe and see things they can't possibly share in a relatable way. Not everything of course, but your feeling of your hands strikes me as something you certainly felt, but likely wasn't anything more than an emotional experience that your brain and consciousness imagined, rather than deduced from logic. But since it felt so real, it felt so 'true' but likely wasn't. I could be wrong though.

That’s the thing with your brain: Everything is kinda like that! All the time.

Most of your brain literally cannot distinguish between fantasy, dream, stories, and actual experiences.

And the parts that do, will never be able to tell if it’s all just made up.

Philosophically, there is no ”reality“ but that what you perceive. Which, due to relativity, is, well, highly relative too. There is no absolute reality either. You can literally have conflicting facts about even simple things, that both are true, and scientifically verifiably so. (Like ”Who shot first?“. Or ”What particle came first?“.)

So be very wary whenever you are confident about such things. Because that is only possible with enough convenient ignorance.

Let's not confuse what's in our heads and what's outside of them.

Philosophy doesn't get us out of the gravity well, cure diseases, build computers, or feed the hungry. However, it does motivate people to prioritize those things.

>> Let's not confuse what's in our heads and what's outside of them.

Well, everything that is at the boundary of our knowledge is also on the boundary between our heads and outside of them.

Let's say you think your partner loves you. How well do you know that? Do you think you know them well? What's the difference between them realising that they should move on in life later on and having planned it all along (getting rid of you in a few years)?

Do you believe in marriage? Is it something enforced upon us by the culture or is it emergent from each one of us individually? What if I only speak about you yourself? Is happy marriage a 5, 10, 20 year long thing? If your partner dies, how long do you wait before your marry someone else?

I would even go as far as saying that "curing diseases, building computers and feeding the hungry" is something that people with a certain slave mentality tend to think about. They need a rational purpose to live because otherwise they would need to admit they are not rational players - but in the end it's them you lose in the game of life by blaming everybody else for being so _irrational_.


> Let's not confuse what's in our heads and what's outside of them.

You can try not to, but ultimately you will fail because your brain works against you.

Schizophrenia isn't some binary thing one either has or doesn't, it's much more of a scale.

A base level of it is even required for our punny brains to rationalize not just all kinds of basic sensory inputs [0], but tying all kind of abstract human-created constructs together in such a way that it sill ends up making "objective" sense to the individual.

[0] https://www.livescience.com/21275-color-red-blue-scientists....

What do you mean ”outside“?

How can you tell there actually is an outside? (And if you can never tell, why would it matter?)

You're venturing into solipsism and that's a well trod dead end. There's certainly an objective world out there. That's where all the fun stuff happens, you know, the stuff with other people, consensus reality.

According to Wikipedia's definition , psychosis is an abnormal condition of the mind that results in difficulties determining what is real and what is not. Speaking as someone who has taken a very large dose of LSD, the boundary between alerted consciousness(or consciousness at all) and psychosis is very blurry. All of human experience is merely an interpretation of our stimuli, and one person's perception of reality is likely to be quite different from other people.

A key difference between LSD-indused psychosis and schizophrenia is timespan. For most people, the psychosis fades and they just become normal people again. (some people do trigger schizophrenia that persists after their trips, though it's rare)

[1] https://en.wikipedia.org/wiki/Psychosis?wprov=sfla1

Personally I have always had amplified psychedelic experiences when pairing them with cannabis and since using psychedelics, I've been much more sensitive to thc. It's weird that people have so many different experiences from those chemicals.

For this reason, I am very selective about using THC. Unless I've also had some alcohol, it'll typically induce anxiety for me. Kudos to those who can enjoy it though.

I had the same experience during my high school and college years. THC consumption (with alcohol or without) consistently induced anxiety (sometimes so much as to induce mini panic-attacks).

Fast-forward five or so years, and I gave it another shot out of curiosity. Interestingly enough, my experience was starkly different. I guess you could say I experienced the traditional side-effects that I had missed my first time around. What's most notable is the subtle after-glow I would feel days after using THC.

I have since been using THC while practicing mindfulness and the benefits have been enumerable! It's quite interesting what role age, set, setting, etc. can have during these experiences.

If you're enjoying it with mindfulness it might also be good with cardio. A tiny bit before 45 minutes on a bike along with some music really makes the time fly.

I do this myself. Cycling is much more enjoyable this way. Even better with edibles and a long distance ride.

Very much so! The combination with an endorphin rush is pretty nice afterwards too.

Kinda sounds to me you used sativa at first, then switched to indica and that's pretty much exactly how that usually works. They have significantly different "highs" and sativa can feel antsy and uncomfortable for already anxious people.

Not necessarily: I always had anxiety issues with cannabis until I tried a pure sativa strain. The problem is that indica gives we weird bodily sensations which trigger my anxiety, whereas sativa only affects my mind.

I think the important thing is that people can experiment in a controlled way. It wasn't until cannabis became legal that I could compare strains and figure out what exactly was causing my anxiety.

An alternative explanation is "No man ever steps in the same river twice, for it's not the same river and he's not the same man."

Certainly holds true for me: the experience, it turns out, depends more on where I am in that stage of life than the substance in question. Cannabis is radically different for me now (at 30-something and after several intense psychedelic experiences) than at 19 or 20 when I first tried it.

And...I'm not assuming you're a man :)

Anecdotally, I find it fascinating that many people find cannabis induces anxiety, while many others use cannabis as a treatment or coping mechanism for anxiety. I'm sure the strain, strength, and exact blend of cannabinoids are relevant factors (and perhaps a bit of placebo/psychosoma based on past experiences), but I suspect if one controlled for all those variables, we'd still see wildly different effects w/r/t anxiety, based on individual brain differences alone.

There are definitely a lot of variables to consider. Method of consumption - I prefer not to smoke things, so I would use edibles.

Strain, strength, psychosoma, as you mention. Psychosoma can be affected by location, time of day (light out or dark out), the company you are in, legality, or potential work-related ramifications, etc.

I _do not recommend_ this at all, but if you want to have an anxious episode, consuming a 10MG THC edible on an empty stomach, while alone, will likely do it. You may find yourself repeatedly Googling "Am I going to die?!", and then forgetting the answer 10 seconds later, for about 90 minutes.

That said, there have been times where I've enjoyed it. Being in a familiar environment, with people I trust, having eaten food, and maybe a drink or two, tends to nullify the anxiety and allow for a relaxing experience. I find similar benefits from meditation though, so I have little reason to use THC these days.

i find it hard to believe that 10mg would do that to me, but that's mostly because I've taken a ~50mg edible (about 1/3 of a 150mg brownie) on an empty stomach and didn't particularly feel super anxious. i certainly was effected, but all in all i ended up finishing that whole brownie and just felt really nice. but i had a fairly strong tolerance at the time and i am a fairly overweight person with a slow metabolism so those things probably contributed. ill have to try again at some point in the future when I'm in better shape and have little-to-no tolerance because that genuinely sounds like a fun time to me.

kinda weird but i find experiencing anxiogenic effects and then calming my mind and letting them go to be an extremely enjoyable experience with mind altering substances. huge part of why i used to abuse diphenhydramine regularly, other than seeing my friends the shadow people!

I consistently have a similar response to the parent. I used to consume a lot in college, but since slowed down to very infrequent usage, primarily because I found I started having anxiety when using it. It started with a vague sort of "is that the cops" kind of thing, but quickly evolved into panic about my health, and overpowering existential dread.

I can still enjoy a very small dose, preferably in the company of others, like at a party or something.

You might find the website leafly.com interesting. I found it while developing a website for a company. They list different types of cannabis & their effects based on what it contains.

I always had the feeling it would raise my heart rate, which usually leads to anxiety for me.

But I have a really low heart rate. It's around 30 when I wake up in the morning and usually 50-60 during the day. So I guess pretty much everything could raise my heart rate, haha.

There was some research done on psychedelic hallucinations which revealed that there is actually less sensory input and that so filters are not disabled - they just have less work as there is less input.

With less input the brain hallucinates to fill in the gaps. It may feel like the doors are being opened to allow the outside in but hallucinogens close the outside off. Your heightened perception of external things when on psychedelics are hallucinations occurring in your brain and not some objective information being transmitted from outside

What socks? :D

Try heart beat, breathing, blood flowing through you, your intestines working, air going through hairs and across your snin, saliva being squeezed out of your mouth's glands, your teeth and tongue touching everything in there, any speck of dust under your finger and toe nails, … did I miss anything?

As somebody who is way more aware of these things way too often: Not fun!

i have horrible adhd (diagnosed, both as a child and as an adult) and i think i already don't have very many filters... And I liked the small amount of shrooms i've had... but I do worry if i try it more then i'll end up without any filters!

William James wrote, “The art of being wise is the art of knowing what to overlook.”

He was also a proponent (later in his career anyway) of the idea that brains act as filters on an expanded field of consciousness. I don’t recall if this specific detail comes more from him or from Myers, but the gist is that consciousness exists independently from bodies, and brains evolved to filter out all but the most useful perceptions that contribute to bodily survival. The last half of that agrees nicely with this article.

James did a lot of work on the nature of embodied experience and was rigorous—foundational to the field of psychology, in fact—when studying how cognition and sensation interact. And a hundred years later, we still don’t have conclusive evidence that brains produce consciousness; we assume it to be the case because physicalist interpretations have worked really well everywhere else in the sciences.

I'm more than a little surprised that this article makes no mention of ADHD. There is an entire group of people with a medical condition that causes problems with attention regulation and it is not used to test the various models for attention explained in here?

(Also speaking as someone with an ADD diagnosis myself)

It does:

>Halassa is particularly intrigued by what the connection between attention and the basal ganglia might reveal about conditions like attention deficit hyperactivity disorder and autism, which often manifest as hypersensitivity to certain kinds of inputs.

Ah, I did a quick CTRL+F for "ADHD" and found nothing. Thank you

This makes sense to me and maybe I'm reading this wrong, but it explains why I can't find my keys when they're in my hand.

I would love some kind of cure or treatment for misophonia. I've suspected my problem was not being able to filter sounds properly, but I can't think of any solution other than physically filtering sounds externally.

I've recently had a misophonia experience while waiting for my wife and kid. The sound was coming from a street party and while I was quite far from it, the sub-woofer bass gave me great discomfort and anxiety, there was no way for me to get away from it as the sound was everywhere. I tried covering my ears but that was not much help. I had to sit down and forcefully relax. When my wife showed up, it was hard to communicate, but she didn't seem as bothered as I was. I usually don't have anxiety or I've learn to control it quite well but this episode was quite concerning to me. Do you get bothered by hi or low frequencies or both?

It doesn't seem to be a property of the sound itself. It is more about me knowing that it is being caused by a person who has the power to stop, but doesn't. If you had the same sound being caused by nature and I knew for an absolute fact that it was outside of anyone's control it wouldn't bother me.

Bass sounds from down the hall or across the street definitely falls under the category of sounds that greatly irritate me. I would inevitably call the cops if I couldn't get them to stop even though I want them to be able to play their music as it makes me irrationally upset.

The kinds of sounds that annoy me on a daily basis are people eating loudly or talking too much. I bought some pretty nice sound canceling headphones so that I can avoid such sounds when I can. I would not be capable of working in an office otherwise.

That's very interesting but I want to know more. The work described in the article only traces a likely attention circuit in the brain (... of mice, but OK). I want to know how this circuit works. How is it that we know what needs to be attended to and what to filter out? What turns the knobs of attention?

When I'm looking for my keys, I know what I'm looking for so I can see how my attention may know what to focus on and what to ignore. Perhaps, when I'm driving down the road and an animal darts across it, I know to focus on it because I have a propensity to pay attention to sudden movements. I can see how that would be very useful to have indeed.

But when there is nothing guiding my attention, like an object of interest or a motion- it's still on and it can still focus. And it can still surprise me.

Last year I had two examples of this. I was on a boat with some friends and I suddendly noticed a cruise liner far off in the distance. It was blending with its surroundings (particularly the mountaints behind it) and so even when I pointed it out to my friends they could not see it for a minute or so, until it moved closer. Another time, I noticed a military helicopter flying across a hilltop. I pointed it out to my mother and again she couldn't see it. My eyes picked both objects out and I was just gazing towards them semi-distracted not expecting anything to be there... how? And why? And how about all the other times I've missed similar information right before my eyes?

How is it that we know what to pay attention to and what to ignore? How do we know what is relevant?

This study seems way too low-level for the type of knowledge that you're trying to extract. My intuition is that you're going to learn more (about your subjective experience which you're trying to do) from AI neural networks with attention mechanisms (there is a lot of info about it like https://www.youtube.com/watch?v=W2rWgXJBZhU) than from this.

This is exactly why we all need to be incredibly judicious in what we expose ourselves to -- the people we surround ourselves with with family, work, and social life, the content we read, watch or listen to, and the emotions we absorb from the communities around us.

Sometimes our filters can handle it all, a lot of times it can't. And a lot of modernity, with always-connected internet devices, outrage porn "news", and sky-is-falling political hacks everywhere, can be overwhelming and frankly exhausting.

I always recommend disconnecting, taking a breather, and enjoying the serenity of quiet. Not working in toxic environments with crummy colleagues, and certainly not being dragged into the daily grind of content farm media companies. It's a huge benefit to one's mental health and emotional stability.

You might be interested in this paper (of mine) which predicted most of the results of the paper in the thread title.


Another article reinforcing my belief that framing AGI research as a quest for "human-level" AI is misguided. The type of intelligence we are looking for is actually animal intelligence. The higher level human abilities are mainly just higher levels of characteristics that most animals have.

The idea is to make artificual human intelligence so that it can help with tasks that humans can do. If we make rabbit AI, it's not particularly useful, and while I am sure it can be a stepping stone (but we already have plenty of those, starting a model of a neuron), the goal is a human AI (and beyond). The human AI is one of the most important steps and points on the jorney, much more so than a rabbit AI. So not misguided at all.

Point is that animal AI is the stepping stone because it has almost all of the human abilities. Where as aiming for higher level human abilities is the wrong starting point.

Filtering is in some sense deconvolution. It makes sense it would be deconvolution.

This is innate knowledge that is finally being verified by science -- eliminating distractions is as much about removing the need to filter as it is about creating the circumstances for increasing concentration

For precisely this reason I am such a stickler for proper professional dress: I find printed T's and athleisure utterly annoying and the cost of filtering out my colleagues fashion choices over the long term leads to a huge cognitive load whereas if we could all work within the established paradigm we'd all attain a way better state of flow

Guess we'll have to wait another century for the science to prove what everyone already knew since antiquity before anyone in the tech industry deigns to wear adult clothes - apologies for the dig but I have points to burn and a desire to be validated as counterculture

Why stop at professional dress? Every citizen should dress in the exact same attire with a toned down color like grey, so not only lesser distractions to productivity, but cheaper and more efficient manufacturing processes. Same goes for buildings, cars and all other products. Let us just grey everywhere and focused efficiency and productivity.

That's the whole point! Tshirt culture effectively leads to that dystopia where everyone wears a jumper -- it's ironic but professional adult dress done right preserves the individuality. I challenge you to see the wisdom inherent in this unpopular opinion

Hey! Can you not tell when someone is on your side? I said grey collared shirts and ironed trousers for everyone. Grey all things. Good citizens must be allowed to focus on productivity.

I'm telling you I want colors, and more of them, but there's a difference between living in a world that children made and being a true adult -- most of us in this industry are crashing and burning in our 30's and 40's and it's not pretty

I'm on your side too orange8, but we went to different universities and had different childhood experiences and now our shared vision is getting cloudy with all this corporate hoopla imposed on us by the man

I am sorry you've had bad experiences within the industry and maybe even childhood. Stay strong and seek those around you for help, even if its just a chat.

And that's another reason I wear a danged tie, so people can recognize that I'm a little different from the hoi polloi eager to please their managers with feature after feature and ticket after ticket -- believe it or not I'm an extreme programmer in the strictest sense, perhaps not a 10x but definitely a 1% mind body and spirit is geared towards computer science believe me, another reason I wear silk, as a nod to the engineers who came before me and worked on the enigma or the Apollo space mission

I've had terrible experiences in this industry too -- look at TechLead, his wife left him! but we're being forged into something stronger than steel -- that's why I wear a silk tie, not because I'm trying to be some kind of corporate drone.. as Simon Sinek says, 'Start with why' -- nothing matters per se, but for the meaning behind it

Also, if it's coerced, it won't work either, but at this point tshirt culture is coerced just nobody has really tried going against it -- try wearing a proper shirt and tie as an engineer, people won't even ask if you're going to an interview any more like they used to

The whole premise of Zuckerberg and his contemporaries wearing the same tshirt every day is precisely to be good worker robots like you describe whereas dressing up ironically gives the finger to the technology industrial complex and frees one to express their own preference

Before you 'yea but...' however understand that the trade-off is that we must agree to some form of standardization and effectively it's formal business dress

If everyone else seems to be doing fine and only you have the problem maybe you should look a little closer to home to find a resolution.

And by the way, I'm not the only one suffering, check out this poor guy who permanently deleted his Facebook account by taking a dive off the fourth floor --


None of us an island -- it's called interdependence

Everyone's struggling without knowing it, look at society as a whole and the planet earth, it was the best of times and the worst of times

That line of reasoning doesn't work on a 10x programmer like myself, I'm above the mere mortals. Save it for the likes of Adam Neumann

This is exactly the reason why our industry suffers from gross diversity problems -- everyone who 'fits in' telling everyone else it's their fault for not fitting in -- oh sweet irony of ironies bring on the downvotes

You are literally taking a recent publication about attentional mechanisms in the brain and hijacking them to explain why you're annoyed with t-shirts, then turning it into a commentary on society.

I think you could use some perspective. This research is not so concrete that the application even makes sense.

Confirmation Bias! Tell me you never make the evidence fit the facts and not the other way around?

i do that sometimes, but i do my best to acknowledge that im going to be doing so before doing it, rather than after :)

My theory is that we've thrown out a large part of our humanity along with the bath water and technology of today is akin to the fire granted us by the mythical Prometheus. We're so busy dancing amongst the flames in our rags we don't notice that it's our humanity burning

i am not entirely disinclined to agree with that statement, at least as far as the uneducated masses go. but there are certainly those that know how to properly wield the fire and work towards the progression of humanity and i think it's somewhat silly to entirely discount them as they are the ones who have gotten us this far.

Yea, they're the ones wearing the puffy vests -> https://www.businessoffashion.com/articles/intelligence/monc...

Distractions are in the eye of the beholder ironically. Have you considered that /you/ are more of a distraction to them with your obsession with "being adult" to your own expectations - from childhood no less?

Just because imposing your prejudices on others makes you have to think less doesn't mean it is a good idea universally.

Yes, I think about it a lot, that's what makes me modest. I have people who's faces I can't remember but their asinine t-shirts are burned into my retinas. Managers who wore the same damned 'Reading Rainbow' tshirt days on end. Fuck you Paul!

I actually agree. The lack of seriousness in their dress betrays their lack of respect towards their work, and towards themselves.

Yea pimpin'! and those damned fleece vests put my high school religion teachers to shame

It all started with some engineers at commodore trying to show how fun loving they were and quickly became a fool's fashion show of kitschy tired old rags

>> It all started with some engineers at commodore trying to show how fun loving they were and quickly became a fool's fashion show of kitschy tired old rags

This just goes on to show how badly you are familiar with fashion.

Fleece vests come from the 90s trading floors. The traders would use shirts, then management started to reduce the temperature on the floors to make the traders more efficient. Vest was a great way not to get cold or too hot on the floor. Thus fleece vests are now associated with finance people.

Funny enough I found an article on vests just this morning on digg -- do you ever experience these weird synchronicities?


I'm talking about the original nexus of homebrew computing and gaming that brought us tech fashion, but this is a very interesting tidbit of esoterica I will cherish

>Yea pimpin'

Masterful trolling, or epic unawareness.

Dude, I grew up listening to gangsta rap and punk rock -- I always believed we were out to overturn the machine, not become it through fragile sensibilities and asinine perpetual adolescence --

Or they see their work more as an extension of themselves when they can dress as themselves

In lab animals!

Not necessarily applicable 1:1 in humans.

This is also how God forgets it is the entire fucking universe so that it can have a human experience and come to know itself.

Edit: See the comments on psilocybin above and read them from a spiritual perspective, try it on. https://www.youtube.com/watch?v=jmBQRb5iuMg

Since this account seems to have gone single-agenda and you've ignored our request to stop posting these links, I've banned the account until we get some indication that you want to use HN as intended, i.e. for intellectual curiosity on an unpredictable range of topics. That's not to invalidate your spiritual path in any way, it's just that repetition is the mother of offtopicness on HN.

Thanks for handling this so well.

Is there a place I can suggest features? I could have avoided a ban if I had seen your first warning.

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