What the actual science says about "brain rot"

In 2022, a lab in Munich did something that I've been wanting to see. They gave

60 people a cognitive test, then sent them away for a 10-minute break, and then tested them again. Now, the difference was the break. Some people

just sat there, some scrolled on Twitter, some watched a normal YouTube video, and some went on TikTok. So, whose brain changed during that time? This is one of the few experiments that I've been able to dig up that has

time? This is one of the few experiments that I've been able to dig up that has actually tested the idea of brain rot. But the science is starting to catch up to the fact that short form video feeds are everywhere. And almost all of the

commentary says that they're making us dumber. >> I cannot physically bring myself to study.

>> I'm addicted, too. We're all addicted to this. >> Oh, no. It's >> horrible for you.

>> Oh, and we're giving kids just the attention span of a walnut. This is

awkward because we make shorts and it has introduced us to a bunch of new viewers. If Brain Rod is real, then we might be part of the problem.

viewers. If Brain Rod is real, then we might be part of the problem.

>> I do have a lot of skepticism whenever there's a claim that like some new thing is fundamentally changing the way that humans operate. >> Yeah. Apparently, Socrates thought that writing was going to ruin our minds and you know, people worried about novels

being addictive and the telegraph and all of that. Like on Howtown, we don't just take the conventional wisdom. >> We're not running on vibes over here.

We're trying to see if there's anything behind the vibes. >> So, I went hunting for evidence. We've

heard about shrinking attention spans since the start of the smartphone era, but how can we measure those? And what are the studies saying about the video feeds specifically? After 10 minutes of swiping through shorts, do people really think any worse?

feeds specifically? After 10 minutes of swiping through shorts, do people really think any worse?

First, I wanted to know what makes this new format different from the hours of television that people watch every day. And you can hear it in how the companies talk about their own product. See, last year, a bunch of private conversations

between Tik Tok employees came to light after 14 US states investigated and sued the company.

>> This is multiple lawsuits coming from individual states attorney general, and the action alleges that Tik Tok exploits and harms young users. The state

attorneys had agreed to black out the confidential materials, and I found the breadth of these redactions odd. That's a local reporter named Sylvia Goodman.

She discovered that the redactions in the Kentucky complaint had not been done correctly. I copy and pasted it all out into a fresh document, and I could read

correctly. I copy and pasted it all out into a fresh document, and I could read all of those redactions. I'll be honest, my jaw was on the floor reading some of this. The document showed Tik Tok employees openly grappling with the

this. The document showed Tik Tok employees openly grappling with the potential harm of the bold glamour filter. bold glamour filter. This is without the filter.

>> They admitted that those screen time reminders were a good talking point, but not altogether effective. One sentence that really stood out to me came from an

altogether effective. One sentence that really stood out to me came from an internal document titled digital well-being. >> Tik Tok's success can largely be attributed to strong out-of-the-box personalization and automation, which limits user agency.

>> We hear a lot about that personalization. That's the famous algorithm that decides what to show you based on what you watch and what people with similar watch behavior watch. But I want to zero in on that last part about

how the interface limits user agency. They're saying that Tik Tok wins by making fewer things feel like your decision. And I think that's the key to understanding what short form video feeds might be doing to our minds. And

since we use that word feed, let's roll with the food analogy.

The restaurants we know have a menu. You browse, you pick something, you eat it.

Streaming television is that kind of restaurant. YouTube is too, or it was.

Their big innovation is that the menus are personalized based on what you've eaten there in the past. Now, imagine a restaurant without menus where you sit down, open your mouth, and a device places a morsel of something

onto your tongue. You don't get another bite until you eat it or spit it out. By

measuring your chew time, the restaurant can adjust the lineup of bites to feature more of the flavors that you tend to swallow. But they don't just hit you with the same flavor time after time. They can also test out some unexpected morsels

because even if it's not your favorite, it's just a bite. And there's another one waiting that might be amazing. Without a menu, you lose the experience

of choosing, but you gain the experience of being surprised over and over and over again.

Plus, a lot more people can make morsels than can make a whole menu. So, this

restaurant can recruit way more cooks trying way more tricks to make their morsels tasty.

This restaurant is Tik Tok and reals and YouTube shorts and all of the other imitators. and it is probably the most engaging media interface that I've ever

imitators. and it is probably the most engaging media interface that I've ever seen. Just in terms of sheer entertainment by watch time. There's a

seen. Just in terms of sheer entertainment by watch time. There's a

catch, though. This sequential feeding system wouldn't work if the dishes were big or complicated. It only works with morsels. If you take away the user's agency, you arrive at short form. We've seen this happen before with Tinder.

Instead of a dating app based on a menu, they showed one profile at a time, forcing feedback from the swiper. And what happened? The profiles became short form. Just photos, a couple of words, and an algorithm that encodes our

form. Just photos, a couple of words, and an algorithm that encodes our subconscious responses more than our reflective intentions. Maybe you noticed that all the dating apps became Tinder. So, is all of media becoming Tik Tok?

I've been trying to figure out just how much human attention has shifted into these feeds, but only the platforms know that and they don't release the data.

But they do these quarterly calls with investors. And if you go back through the past few years, you can kind of hear just how big of a response Meta and YouTube have made to the rise of Tik Tok. >> Reals already makes up more than 20% of

the time, 50% of the time that people spend on Instagram. >> Over 15 billion views each day. 30

billion billion plus 70 billion. >> We now average over 200 billion daily views on YouTube shorts.

>> Social media has gone through two eras so far. First was when all content was from friends, family, and accounts that you followed directly. The second was when we added all of the creator content. Now, as AI makes it easier to

create and remix content, we're going to add yet another huge corpus of content on top of those.

It's really easy for me to think of this as the bowl of potato chips that someone sticks on the table that you didn't order, but it's there, so you snack on it.

>> No one can eat just one. >> And it makes me wonder if How town shorts are kind of like, do you know those like pe-shaped potato chips?

>> Uh-huh. Right. Right. Right. I know what you're talking about. >> It's like a green Cheeto.

>> There's a version of this that's like, but our chips are made of vegetables. I

suppose it's no surprise that a bottomless personalized mystery snack dispenser could take over our media diets, but there is such thing as a healthy snack, right? So, I'm going to tell you about all the research that

I've read about this and then maybe we can decide how we feel about it.

>> Yeah. Great. Yeah. It's interesting. As you've been researching all this, I have been feeling especially scatterbrained. I'm like distracted by the news. I've

been moving between two different continents. So, it's a happy coincidence that the sponsor for this week's episode is Headspace, the mental health platform.

>> Did you try it? >> Yeah. Yeah. They sent me a free subscription and I've been taking their finding focus course, which is basically 10-minute sessions of guided meditation, and it's been really nice, honestly, to have that break in my day. A couple days

ago, I actually just did one while I was waiting for the bus. You know, I've done a fair amount of reporting on mindfulness meditation over the years, and there's a real growing body of evidence from some pretty robust studies that it can improve your working memory. It can improve your ability to sustain

attention. In one study, people who meditated with headsp space for a month

attention. In one study, people who meditated with headsp space for a month were less distractable than a control group who did these standard brain training exercises, things like puzzles and memory tasks. So, if you, dear viewer, want to help your brain to focus, you want to learn to meditate,

maybe you just want to have these calm moments built into your day, you can start Headspace for free by following the link in our description box or scanning this QR code that's on screen. Usually, it's just a twoe trial, but

with this link, you get a full 60 days completely free. Before we get to Tik Tok, there's a bigger question to answer. Have our attention spans really shrunk? According to a 2015 post by Time magazine, yes, they're now shorter than

shrunk? According to a 2015 post by Time magazine, yes, they're now shorter than a goldfish. But this is one of those myths that won't die. >> Here's a fun fact.

a goldfish. But this is one of those myths that won't die. >> Here's a fun fact.

>> Some researchers have concluded that our attention span is now shorter.

>> Shorter than a goldfish. >> That's a scientific fact. >> The claim came from a report published by Microsoft which had this graphic showing our attention span declining from 12 seconds to 8 seconds. But they were citing something called statistic

brain which in turn cited these sources. And when journalists tried to track down those sources, they didn't exist. The numbers were entirely made up for both the humans and the goldfish. So what would it really take to measure

attention spans? Well, I talked to one of the few people who have tried. My

attention spans? Well, I talked to one of the few people who have tried. My

name is Gloria Mark. She's written a book called Attention Span. And way back in 2003, she convinced an investment management company to let her peek over the shoulders of 14 of their employees as they worked. >> And we would just observe them and with

stopwatches, every time they changed to do something else, we would click on the the stopwatch and it was very, very tiring. Those employees spent about 2 and 1/2 minutes working on their computers before they switched to

checking email or doing something else. Fast forward to 2012. She convinces

another workplace to let her install software that tracks how often their employees click from one window to another and finds that they switch every 75 seconds on average. Now it's closer to 40. >> So yes, empirically we can say that on

screens attention spans have shortened. >> It's a little tricky because obviously we have this method switch like without that dot at 2004 the trend doesn't look as dramatic, right? It's sort of funny to me to think about the adjudicators or

the watchers in that first test were also having their attentions tested.

Like were they able to catch like they're also having to focus? The other

big question I would have is like is this measuring our ability to focus or just how much distracting stuff there is in our lives. What I'm worried about is that I'm no longer able to read a book for 6 hours like I did when I was 12.

>> Has something changed about your brain? >> Yeah. Has has something changed about the ability of my brain? It's obvious to me that something has changed about the way that computers work. Like, yeah, I've just got notifications. There's

literal sounds that are telling me you should be distracted by this other thing right now. And so, I still have I'm still curious about like if there's

right now. And so, I still have I'm still curious about like if there's actual damage being done to our mental systems. I guess >> the advantage of Gloria Mark's approach is that it captures real life. It's not just bringing people into a laboratory,

having them sit for an hour in front of a computer, but we actually observed what people did over the day in the course of their actual work. The

limitation is that it can't distinguish between these three different influences on our ability to focus. There's our attentional capacity. That's what we generally think of when we say attention span. Then there's our motivation, how

much we need or care about focusing on this task. And there's competition. How

much is our environment distracting us? Now, in a lab, they can get closer to controlling for motivation and competition. But the tasks that they give people don't look anything like real life. Let me show you. This is a

classic attention test. They tell you to memorize this image. And then you go through these rows, crossing out the items that match the one that you memorized. You get 20 seconds per row. There's 14 rows. They look at how many

memorized. You get 20 seconds per row. There's 14 rows. They look at how many errors you make, how fast you work, whether you get worse over time. And on

this test, performance in adults has actually been increasing. That's

according to a study that compiled scores from three decades and 32 countries. In children, overall performance hasn't changed, but their test taking style has. They've become

faster, making more errors, but also completing more items. Now, researchers who run lab tests like these don't claim to be measuring attention span. I think

we often in daily life, and I even do this myself, we just talk about attention, and it feels obvious, like we know what it means to pay attention, but actually if we give people different tasks, we can see that there's distinct components of attention that aren't necessarily related to each other.

>> Monica Rosenberg studies patterns of brain activity during attention tests. the same.

>> When I'm watching a really engaging movie, like my lab collected data as people watched a Hitchcock film and YouTube videos about cooking, is this the same kind of attention or is there something fundamentally different about

right being engaged in a narrative that I'm motivated to follow versus forcing myself to do this boring task? Um, and it, you know, it turns out there's some similarities, but there's also some differences. And so I think how well I

do on one task with pictures is not indicative of how well I pay attention all the time in all contexts. It's certainly related, but it's not a perfect measure. So let's set aside the concept of attention spans. It's a

perfect measure. So let's set aside the concept of attention spans. It's a

really fuzzy term. It's hard to measure. The sharper question to ask is if you binge short form video, what exactly gets worse? Is it your memory? Your

reasoning? That's what the next few studies are trying to pin down.

If you ask, do people who say they're addicted to short form video also have trouble focusing? So far, the answer to that seems to be yes. A recent review of

trouble focusing? So far, the answer to that seems to be yes. A recent review of 14 studies found that increased SFV use, that's short form video, was associated with poorer cognition, including attention and inhibitory control. But

whenever you see that term was associated with that scientist code for we're not saying this causes the problem, >> right? It's sort of our social media and teen health all over again where it's are depressed teens becoming depressed

because they are on social media or are they seeking it out?

>> Yeah, I think this is the question with basically all of the harmful effects that people are attributing to these new technologies is almost all the research can't distinguish correlation from causation. But there are a few experimental studies that I wanted to highlight. There are at least two

different cognitive tests where people perform worse after scrolling a shorts feed. One is a kind of trick question quiz and the other is about whether you

feed. One is a kind of trick question quiz and the other is about whether you can remember to do something that you plan to do. So first there's a measure based on these three questions. >> A bat and a ball cost $110 in total. The

bat cost $1 more than the ball. How much does the ball cost? This is supposed to capture analytical thinking. To get these questions right, you have to switch out of autopilot like

thinking. To get these questions right, you have to switch out of autopilot like your gut is screaming >> 10 cents and you need to override that.

72 college students at Ping University in Beijing took this test after either spending 30 minutes scrolling Tik Tok or the Chinese version of Tik Tok or 30 minutes reading. And the Tik Tok group did worse. The researchers wanted to

minutes reading. And the Tik Tok group did worse. The researchers wanted to know does what you watch matter? So, they ran a second study, but this time people watched either a cute animals playlist or a science experiments

playlist. They also changed how people watch. Some could swipe through the

playlist. They also changed how people watch. Some could swipe through the videos like a normal feed. Others had to sit and watch the same clips stitched together into one long video. And here's what they found. It didn't matter whether you watched

animals or science, but the swiping groups consistently did worse on the cognitive reflection test. They got 38 fewer questions right out of the three

questions total. That's 12% of the scale after 30 minutes from just swiping alone.

questions total. That's 12% of the scale after 30 minutes from just swiping alone.

>> Okay. Interesting. So, if you're you're subjected to essentially just a montage of videos that you don't have control over, you are not degrading your analytical thinking as much as if you're swiping through and getting to just skip

whenever you are bored. It's sort of interesting because you you think of that decision is interacting with the interface, right? That decision is cognitively more intense than just sitting back and letting something happen to you, right?

>> Yeah. Unless boredom is cognitively intense in a way that we don't recognize.

>> Okay. So, that's one test that short form video makes you worse at. The other

is a test of prospective memory, which is when you remember to do something that you intended to do, like picking up the dry cleaning or joining a Zoom meeting or taking a medication that you're supposed to take. Researchers at

the University of Munich wanted to know how short form video feeds affect that ability >> because it was coming from a general observation that like if you scroll a bit, you feel like don't want to say that you feel like new, but like you kind of

>> dissociate. Yeah. Yeah. Dissociated a bit. So it was something like we said

>> dissociate. Yeah. Yeah. Dissociated a bit. So it was something like we said okay is this actually really happening like and we felt that. So we said okay let's figure out uh how we can you know make this uh solid user study and

investigate what can be a cognitive um function that be associated.

>> So how would you test perspective memory? >> Boy oh boy. Well it feels like yeah we're getting tested all the time. If you tell me to do something and then you wait 30 minutes and see if I did it. Is that long enough to be considered

perspective memory or does it have to be like I know I have a meeting on Wednesday at 1 and do you show up at the meeting? Is that is there a time scale involved in what is considered perspective memory? >> Yeah. Well, I mean the way that the way

that psychologists define it for their purposes is is even much shorter than that because >> they need a way to measure it in the lab >> with subjects that they don't have access to for very long. So, the way they try to capture perspective memory,

which is this idea of remembering a previous goal or intention, is they embed a task within a task. So, you're going to try this out.

>> No. Great. I should have slept more last night. >> Fly sheet.

>> The subjects were told to press N on their keyboard if the word on the screen is a real word.

>> My heart is racing. >> And M if it's a fake word. >> No. But if they saw the words blue, purple, or green, they were supposed to press Q, W, or E, respectively.

>> Purple is that's the perspective memory task. >> Nope, I did it wrong.

I got it wrong already. I already know. Houseman joust green. I love green. They had

people do this task and then take a 10-minute break in which they either just rested, scrolled Twitter, watched a YouTube video, or scrolled Tik Tok, and then they took the test again. When they compared the scores from before the

break and after the break, the performance on the real word, fake word task was the same. But for the blue, purple, green task, where they needed to remember that second intention, one group saw a big drop in their scores. It

was the group that scrolled Tik Tok during the break. >> What this is basically getting at is if you should be keeping something in mind, you lose that with the scrolling behavior, >> but not just scrolling because Twitter is a scroll behavior as well,

>> right? That's true. It's short form video specifically.

>> right? That's true. It's short form video specifically.

>> That study took place in Germany, but I was able to give this test to Adam in English because researchers in the UK replicated it in their own sample of 45 students. And this time they tested different ways of watching short form

students. And this time they tested different ways of watching short form video. One group was limited to 10 swipes. The other group was allowed to

video. One group was limited to 10 swipes. The other group was allowed to swipe as much as they wanted. And there was a control group that just sat quietly. The group that watched shorts but was limited to 10 swipes didn't see

quietly. The group that watched shorts but was limited to 10 swipes didn't see a drop in their performance. The unlimited swiping group did. So again, it's like

something about just being able to do this mindlessly is is the problem. So, if

you're watching this in a clipped short, don't swipe away.

>> Actually, what you should do is download all the Howtown shorts, but watch them in one big stream. >> There you go. >> Um, so that's basically where we're at with this with the research. There's a few of these experimental studies.

They're using a few different types of cognitive tests, none of which really map on to our popular conception of attention span, but are related

cognitive skills. and they're raising a few red flags, but obviously the the

cognitive skills. and they're raising a few red flags, but obviously the the caveats of small samples um and tasks that are very different from our

everyday lives. Now, I want to know if I'm scrolling TikTok every night before

everyday lives. Now, I want to know if I'm scrolling TikTok every night before bed for 2 hours, am I just generally having a worst perspective memory in my

life, or is that confined to just right after I use it? long-term studies would actually really inform uh and maybe guide better ethics and policy in designing the interface. I think this is actually something that could really

impact the quality of life of people probably and provide evidence that maybe something has to change. >> In 1890, the pioneering American psychologist William James wrote, "My

experience is what I agree to attend to. My experience is what I agree to attend to. And there's more. He said, "Only those items which I notice shape my

to. And there's more. He said, "Only those items which I notice shape my mind. Without selective interest, the consciousness of every creature would be

mind. Without selective interest, the consciousness of every creature would be a gray chaotic indiscriminatic indiscriminately,

my relationship to mangoes will never be the fame. And yet, I keep coming back to this question of user agency or what James called selective interest. Agency

is at the heart of both analytical thinking and perspective memory. Those

weird little tests are basically asking if your brain is on autopilot or if you can slow down, make a turn, remember where you intended to go. It's not just your intentions that get lost. Feeds that nudge the customers into autopilot

tend to nudge the cooks into autopilot, too. >> Scientists just created Here's what would happen.

>> Scientist Here's what happened. Scientist, >> but not everyone. Last time I checked, Smarter Everyday, you guys had not posted anything into the shorts feed. Is that still the case?

>> That's the case. I have elected not to do that because I don't think it's good for people. I don't think the infinite scroll is healthy for our minds. It's

for people. I don't think the infinite scroll is healthy for our minds. It's

easy for me to say this because Smarter Everyday has been around for a while and there's a lot of really awesome people that support the channel, but I think saying no to shorts is powerful. Um, and I think it ultimately increases trust in

the creator. Um, I could be wrong about that, but I don't know. That's where I'm at.

the creator. Um, I could be wrong about that, but I don't know. That's where I'm at.

>> Dustin's such a good guy. Um, yeah. I mean, I think, you know, obviously we want to be acting with integrity and sort of like living our values in all parts of our life, including the way we make this channel, but like having bite-sized information, you know, when I was at NPR, we would make 3minut radio

pieces all the time, right? That was like a pretty typical length. And I

didn't feel like those were bad for the world just because it was a compressed amount of information about a complex subject. I thought like, oh, this is good. Like someone is learning something that they wouldn't otherwise know. The

good. Like someone is learning something that they wouldn't otherwise know. The

question is, do we want to participate in this in these endless scrolls?

>> I don't know if you see these comments sometimes on our shorts. This one says like, "Your contents are the most anti-brain rot content out there. Actually, genuine and very high quality." And then someone responded, "No such thing as anti-brain rot content

quality." And then someone responded, "No such thing as anti-brain rot content when it's short form." >> So, that's basically kind of the question that we need to answer.

>> Yeah. Yeah, that's right. Is there such thing as a good short uh as an anti-brain rot short?

>> What do you think? Is this research strong enough that we should be making a change? Let us know in the comments. You can also find more of my conversation

change? Let us know in the comments. You can also find more of my conversation with Destin and hear Adam and I processing all of this over on our Patreon. And if you're interested in meditation, which is arguably the

Patreon. And if you're interested in meditation, which is arguably the opposite of binging a shorts feed, click the link in our description to try

Headspace free for 60 days. That deal doesn't last. So try it now. See how

your mind responds. Thanks for watching.