Overstimulation Makes You Dumber

00:00:00.200 | Is overstimulation ruining your life last spring of my podcast?

00:00:05.760 | I looked at some data that implied this might be happening.

00:00:08.640 | So today I want to show you a clip from that popular episode where I, I make the

00:00:13.840 | argument that overstimulation is a problem that it's making humans dumber, but that

00:00:19.760 | there's a way that you as an individual can avoid this fate that you can stop

00:00:24.760 | overstimulation from making your own life worse.

00:00:27.760 | I think you're going to enjoy this clip, check it out.

00:00:30.280 | So several people recently sent me the same article.

00:00:33.120 | It was from the financial time.

00:00:34.680 | So it was written by John Byrne Murdoch and it had a provocative headline, have

00:00:38.680 | humans past peak brain power.

00:00:41.520 | So I'm going to take a closer look at this claim.

00:00:44.400 | I have two goals in mind.

00:00:45.600 | First, I want to develop a better understanding of why the data seems to

00:00:50.040 | show that we are getting dumber, but two, I want to use that understanding.

00:00:53.560 | It's my second goal.

00:00:54.280 | Use that understanding to help find practical ways that you as an

00:00:57.560 | individual can push back on that trend and not only not get dumber, but make

00:01:02.400 | sure that you continue to get smarter.

00:01:04.680 | So this article that I was just citing was inspired by some recent analysis that

00:01:10.240 | was released by the organization for economic cooperation development.

00:01:13.320 | They do this regular test called the PISA, which benchmarks teenagers around the

00:01:19.280 | world and their knowledge of math, reading and science.

00:01:22.240 | So we have sort of trends over time.

00:01:23.960 | It's a useful test to kind of understand what's going on.

00:01:26.200 | Um, so they looked at, there's a recent analysis of this.

00:01:29.360 | The article looked at that recent analysis, plus some other tests that have been given worldwide

00:01:33.360 | recently.

00:01:33.920 | And the author of the article made the following conclusion.

00:01:37.760 | I'm quoting here, "Across a range of tests, the average person's ability to reason and solve novel problems

00:01:44.240 | appears to have peaked in the early 2010s and have been declining ever since."

00:01:50.480 | So I have a graph to show here, Jesse, bring up this graph for those who are watching instead

00:01:55.400 | of just listening.

00:01:56.120 | So here's one of the key graphs that indicates this point.

00:01:59.200 | Uh, it shows performance and reasoning and problem solving tests over time.

00:02:03.600 | On the left-hand graph, what you see is a line for science, reading and math, and you can attest,

00:02:09.840 | Jesse, that right around 2012, all those lines go downward.

00:02:14.800 | Uh, that's from the PISA test.

00:02:16.480 | We have a test from an adult on the right.

00:02:18.240 | Literacy, uh, takes a big spill right around 2012 and goes down dramatically ever since.

00:02:25.040 | All right.

00:02:25.200 | So we can bring that graph down.

00:02:26.240 | So that indicates the thesis of the article that, hey, starting the early 2010s, at least

00:02:32.240 | according to test, we're doing worse, worse us being humans.

00:02:36.400 | So why, why are we doing worse?

00:02:40.400 | Well, the article points to an obvious culprit based just on the forensic evidence of the timing.

00:02:44.880 | These trends seem to occur right around that 2012 to 2014 period is where we see these downward

00:02:51.440 | shifts.

00:02:52.800 | That date should sound familiar.

00:02:54.880 | There have been other things that worry us that got more prominently worrisome starting

00:02:58.640 | around that time.

00:02:59.280 | For example, teenage mental health deterioration is another one.

00:03:03.040 | What happened around that 2012 period?

00:03:05.200 | Smartphones became ubiquitous.

00:03:07.680 | This is when we got worldwide ubiquity of smartphones became a reality.

00:03:12.240 | So the article points out correctly.

00:03:14.880 | We seem to be seeing a negative turn on these tests of various reasoning and intelligence

00:03:19.920 | abilities around the time smartphones come and it's been getting worse ever since.

00:03:24.480 | But I don't think it's useful to just leave it there.

00:03:26.880 | So if we just say, yes, smartphones seem to have led to us getting dumber.

00:03:32.160 | It's unclear how we should respond.

00:03:35.040 | We're probably not going to get rid of phones.

00:03:37.840 | Most people need various aspects of the phone and app ecosystem to operate.

00:03:42.640 | So it sort of leaves us without much to do, except for to shrug our shoulders and say,

00:03:46.080 | well, I guess phones may as dumber, but what are we going to do?

00:03:48.160 | It's sort of like cars came along and traffic deaths got higher.

00:03:52.160 | Here's a source of 20,000 new deaths a year that didn't exist before cars, but we kind of need cars.

00:03:57.520 | And it was like, this is just something we're going to have to live with.

00:03:59.600 | It feels that way sometimes when we're dealing with these cognitive impacts of smartphones.

00:04:05.200 | But I think we can do better and I want to do better today.

00:04:08.800 | So I'm going to look closer and I'm going to try to develop a hypothesis that explains at least

00:04:13.600 | partially, specifically why, what mechanisms of smartphones are making us perform worse on

00:04:18.160 | these tests, making us dumber.

00:04:19.520 | Because if we know more specifically what about these things is making us dumber,

00:04:24.080 | then maybe we have a chance of reversing that even without having to get rid of our phones.

00:04:27.920 | So to look closer, what I'm going to do is pull up another graph.

00:04:32.400 | Jesse, bring this up on the screen here.

00:04:33.520 | Here's another graph from this article that gets at what specifically is changing in the smartphone era.

00:04:40.320 | So we see here on the left, a graph over time, measuring percentage of respondents

00:04:45.840 | that are saying they have difficulty thinking or concentrating.

00:04:49.680 | This comes from another survey called Monitoring the Future, which John Byrne Murdoch sort of pulled up.

00:04:53.920 | What you notice here is it's relatively stable difficulty thinking or concentrating

00:04:59.920 | until that same inflection point of around 2012, and then it shoots up.

00:05:03.520 | And we see a aggressive upward trend.

00:05:07.920 | On the right, we have another graph, percentage of people saying they have trouble learning new things.

00:05:11.920 | It's relatively flat starting in 1990.

00:05:14.560 | Again, right around 2012, shoots up.

00:05:17.120 | Same time that difficulty thinking or concentrating shoots up.

00:05:20.320 | So of course, right at the smartphone inflection point, we see mechanistically that people suddenly

00:05:26.640 | reported at much higher rates having difficulty thinking or concentrating and having trouble learning

00:05:31.680 | new things.

00:05:32.160 | All right, we can bring this down, Jesse.

00:05:33.360 | That is where I think we're seeing the effect of smartphones.

00:05:39.040 | And if we look at a little bit closer, why is smartphones now causing us to have difficulty

00:05:43.760 | thinking or concentrating or trouble learning new things?

00:05:46.320 | Keep zooming in.

00:05:47.200 | I believe we can identify what I think of as a cognitive death spiral here.

00:05:51.840 | And here's how I think this works.

00:05:54.400 | So you now have a smartphone.

00:05:56.320 | The phone itself is not the problem, of course.

00:05:58.080 | It's the ecosystem of attention economy that arose around the smartphone.

00:06:02.000 | Pre-smartphone, if you were building a sort of information platform, your Facebook pre-smartphone,

00:06:07.440 | you were building a product that was trying to be maximally useful to users.

00:06:12.240 | I want to make Facebook so useful that people will think to log in and want to be a member of it.

00:06:18.480 | So like all your friends are on here.

00:06:20.480 | That's a marker of this being useful.

00:06:22.720 | You can find out what your friends are up to.

00:06:24.640 | That is a really useful thing.

00:06:26.560 | Post smartphone, we had a shift towards an attention paradigm where the idea now is not being useful,

00:06:31.360 | but capturing as much attention as possible.

00:06:33.440 | They realized users were, you wanted a large user count if you were trying to raise money.

00:06:38.240 | But once you had a company running, you wanted to monetize those users.

00:06:42.640 | And that's a different game.

00:06:44.000 | And this is when the goal of platforms changed to not being as useful as possible,

00:06:47.520 | but being as addictive as possible.

00:06:49.280 | So we get ubiquitous smartphone use pickup around this time.

00:06:52.160 | Why does that cause a cognitive death spiral?

00:06:54.400 | Well, think about what happens.

00:06:55.440 | You have this rhythm in your life of constantly being distracted because

00:06:59.760 | the apps on your phone are designed to grab your attention.

00:07:03.600 | It has faster, more desirable stimuli than other things in your life.

00:07:07.840 | So now you're rewiring these circuits in your brain so that the reward circuits are very much

00:07:13.360 | tuned towards if a phone is nearby, let's focus on that.

00:07:17.200 | Let's have our dopamine cascade focus on the action of looking at that phone,

00:07:22.400 | because that we have learned these circuits have ingrained.

00:07:24.640 | That's going to give us a quicker hit to whatever else we are doing.

00:07:27.440 | And because the phone is ubiquitous, we constantly have those reward circuits firing

00:07:32.240 | because the phone is always there.

00:07:33.520 | The reward is always there.

00:07:36.640 | Look, if you put a donut in front of me, I'm going to build up a reward.

00:07:39.680 | You know, every day at four, you put out donuts at the office.

00:07:41.920 | I will build up a reward circuit where like, I'm really looking forward to that donut.

00:07:45.600 | If you now follow me everywhere I go with a cart of donuts, there's going to be a problem.

00:07:49.520 | Right?

00:07:49.680 | So that's what started happening with the phone.

00:07:50.960 | So now our mind gets rewired to craving this more faster pace of stimuli.

00:07:57.840 | That can directly impact our ability to concentrate because that's distracting us.

00:08:03.600 | We're trying to take a P as a test.

00:08:04.720 | We're going to do worse on it.

00:08:05.680 | It's harder to sort of apply our existing intelligence.

00:08:09.120 | But the reason why I think it creates a cognitive death spiral is that it also means we spend less

00:08:14.400 | time on the type of activities that could make us smarter.

00:08:19.120 | So if two things going on at the same time as our mind gets rewired for faster stimuli,

00:08:24.320 | we have a harder time applying our existing intelligence,

00:08:26.800 | but we also have a harder time engaging in activities that would make us smarter.

00:08:32.880 | Now this is also captured in this article.

00:08:35.520 | Jesse, bring up one more chart here.

00:08:36.960 | What we have on the screen here is a chart showing the decline of reading.

00:08:41.920 | There's two plots on here.

00:08:44.160 | So this is a percentage of U.S. teenagers who read in their leisure time.

00:08:48.880 | One of these plots on here shows who says they hardly ever read.

00:08:53.440 | And the other plot shows who reads almost every day.

00:08:57.440 | So we see the almost every day.

00:08:59.840 | It's like moving mildly down through the 80s and 90s.

00:09:04.720 | Right around 2012, that goes down real sharply.

00:09:08.400 | And the people reporting that they hardly ever read goes up real sharply.

00:09:12.400 | All right, so we can bring that graph down.

00:09:13.600 | So what's this saying?

00:09:15.280 | This is an example of an activity.

00:09:16.640 | Reading is an example of an activity that makes you smarter.

00:09:19.120 | The brain circuits involved in reading makes you smarter.

00:09:23.520 | You can better understand other people.

00:09:25.760 | You can better sustain your attention on abstract targets.

00:09:28.000 | You can better manipulate information and build and construct worlds in your mind.

00:09:31.200 | Reading is calisthenics for your mind.

00:09:33.760 | It is a straight-up exercise for your mind.

00:09:35.440 | It's why it's been at the core of sort of every academic curriculum since the invention of the codex.

00:09:39.840 | So it's one among other activities that we do less of because it requires sustained attention.

00:09:45.360 | And when we rewire our mind for faster stimuli, we're less likely to actually, as we see in that graph, we're less likely to actually spend time doing that.

00:09:52.240 | So we get this double whammy.

00:09:53.440 | We have a hard time applying whatever intelligence we have and we slow down or completely stop the increase of our intelligence that should be happening over time as we do activities that would naturally get us there.

00:10:03.520 | The result, we're dumber and we see it.

00:10:06.720 | Our performance on those tests plummet.

00:10:08.880 | So we're not getting smarter and we're having a harder time applying the intelligence we have.

00:10:13.360 | Okay, so really now what we're talking about, our issue is not with smartphones so much as it is with the specific effect of having a brain rewired for faster stimuli.

00:10:26.720 | And because of this spending less time with activities that foster intelligence.

00:10:31.760 | So if we're looking for a response here, we can actually come up with actions that don't involve us having to go back in time.

00:10:40.960 | Now, before I talk about what that could particularly be, here's the analogy that came to my mind from 60 years ago, right?

00:10:46.560 | We had this issue 60, 70 years ago where in the US, for example, the economy shifted from being primarily industrial agricultural to having this very strong sort of office centric knowledge work sector.

00:10:58.160 | And we noticed in the 1950s and in particular, the 1960s, this issue of we are having health problems at a higher rate than they existed before.

00:11:07.360 | Because before you were probably working on a farm and you were exercising all day long, you were on your feet, you were moving, you were lifting things.

00:11:14.320 | It's very physical.

00:11:15.040 | And now suddenly you're sedentary because you're in an office.

00:11:17.600 | You're not getting that exercise.

00:11:18.800 | This caught us off guard.

00:11:20.160 | Like, oh, that was important.

00:11:22.640 | And we're not getting that anymore.

00:11:23.920 | You know, in the era before bypass surgery, people would just drop dead in their 60s.

00:11:29.200 | That's just how it works.

00:11:29.840 | You just have a heart attack and die in your 60s.

00:11:31.440 | Like, whoa, what's going on here?

00:11:32.560 | How do we respond to that?

00:11:36.000 | Well, we didn't say we need to shut down the offices and go back to the farms.

00:11:40.000 | We said, what was the thing we're missing now from the farms now that we have this new knowledge sector?

00:11:45.200 | Oh, it's the exercise.

00:11:46.480 | Okay.

00:11:46.800 | I guess people need to exercise.

00:11:48.320 | You didn't have to think about that before.

00:11:49.920 | In 1920, you didn't have to think about exercising.

00:11:52.080 | You just got it.

00:11:53.200 | But in 1975, I got to go jogging.

00:11:56.000 | You know, I got to move some weights around because that is out of my life now.

00:12:00.800 | And it was actually pretty important.

00:12:02.160 | That is a good analogy for thinking about this smartphone

00:12:04.640 | induced dumbness issue.

00:12:06.800 | We don't necessarily have to go back to pre-2012 technology era.

00:12:11.600 | But we do now have to think explicitly about increasing our intelligence and maintaining

00:12:17.840 | our ability to hold attention in a way that we didn't have to in 2009.

00:12:21.120 | We just did this naturally.

00:12:23.440 | Now we have to think about it.

00:12:24.640 | That's the mindset shift.

00:12:26.800 | We have to exercise our minds in the same way we learned we have to exercise our bodies.

00:12:30.560 | So what might that mean?

00:12:32.720 | Well, we talk about this a lot on the show.

00:12:35.440 | But just to give you four ideas,

00:12:37.600 | you know, that gets your mind going about how one might have a cognitive exercise routine

00:12:41.840 | and push back on this dumbness trend, you could one, force yourself to read.

00:12:46.640 | Reading is pull-ups and push-ups for your brain.

00:12:49.600 | Read.

00:12:50.960 | Every week, read a book.

00:12:53.360 | Start with things you love, easy to read.

00:12:55.520 | You're excited to read, but force yourself to sit there and read.

00:12:59.280 | The best way to do this is to be outside of arm's reach of a phone.

00:13:04.720 | In fact, be in a completely different room from a phone.

00:13:06.560 | Even better, go for a walk and read on a bench without your phone

00:13:09.920 | so that you don't have to fight against a reward circuit that sees the phone and says,

00:13:14.000 | "It is right there.

00:13:14.640 | We could pick that up.

00:13:15.360 | Dopamine, dopamine, dopamine."

00:13:16.560 | So make your life easier.

00:13:17.440 | But reading is calisthenics for your brain.

00:13:20.320 | More generally, in the constant companion model of your phone,

00:13:22.880 | when you're at home, plug it in in the kitchen.

00:13:24.640 | Go there if you need to look something up.

00:13:27.120 | Go there if you need to check your text messages.

00:13:28.640 | Go there if you need to make a call,

00:13:30.160 | but don't have it with you when you're doing other things.

00:13:32.800 | Again, you want to sort of break out of this pattern of,

00:13:35.440 | "I can at any moment get faster stimuli."

00:13:37.840 | You certainly want to avoid, and I just learned this term.

00:13:41.600 | I don't know if you know this term, Jesse,

00:13:42.720 | but I just learned this term, stimuli stacking.

00:13:44.880 | I don't, no.

00:13:46.720 | I heard this from a younger person.

00:13:48.240 | Shout out to Nate.

00:13:49.600 | Stimuli stacking is where you're consuming multiple streams

00:13:54.320 | of stimulus at the same time.

00:13:55.520 | So you're watching something while checking something on your phone,

00:13:58.880 | and maybe you even have a different device on which you're following something else.

00:14:02.480 | And supposedly, some of the streamers, like Netflix,

00:14:06.880 | are actually redesigning their shows to be more compatible with stimuli stacking.

00:14:11.040 | So if it requires you to have to, if I missed what was said here,

00:14:14.320 | I don't know what's going on, that's a bad show,

00:14:16.000 | because you can't actually look at your phone at the same time and watch that show.

00:14:18.880 | So don't stimuli stack.

00:14:20.160 | We want your mind to be used to like doing one thing for a long piece of time.

00:14:24.960 | Reflection walks is another great one.

00:14:26.960 | Go for a walk with a particular problem you want to solve.

00:14:29.360 | It could be just a problem in your life.

00:14:30.880 | I want to work this through, and your mind is going to be everywhere.

00:14:33.680 | It's going to be squirrel, squirrel, squirrel.

00:14:35.840 | But you keep pulling it back, be in the sunshine, be in the woods.

00:14:39.680 | Get used to just being alone with your own thoughts and manipulating your thoughts.

00:14:43.200 | You will get better at this.

00:14:44.320 | This also pushes back on the negative trends that smartphones are inducing.

00:14:48.800 | And have hobbies that require concentration.

00:14:50.800 | Playing the guitar requires a lot of concentration to get better.

00:14:55.280 | Woodworking requires a lot of concentration to get better.

00:14:58.800 | A particular sport requires a lot of work and focus to actually get better at it.

00:15:03.040 | So have things that require sustained concentration and give you obvious rewards as you get better.

00:15:08.560 | So notable rewards so you feel that appreciation.

00:15:11.520 | All right.

00:15:12.080 | So anyways, I thought that was a cool article.

00:15:13.680 | That's what I think is going on.

00:15:15.040 | It's not just the phone itself makes us dumber.

00:15:20.480 | It's particularly the way that it's rewired our brain, which creates that death spiral.

00:15:25.520 | If we have a harder time applying our intelligence and we don't increase it, so we just push back.

00:15:28.640 | Look, man, when you're in the office building Mad Men in the 1960s, you got to start exercising.

00:15:34.880 | You didn't have to exercise when you're on the farm in the 1940s.

00:15:37.520 | You got to exercise now in the office building in the 1960s.

00:15:40.160 | Well, same thing.

00:15:41.280 | When I was in college in the early 2000s, I didn't have to worry about how do I keep my brain

00:15:46.400 | sharp?

00:15:47.920 | How do I keep getting smarter?

00:15:49.120 | Because we were just doing this all the time.

00:15:51.200 | We had to read books and we didn't have like constant distractions.

00:15:54.080 | And we were often bored and walking long distances in the interminable snow of Hanover, New Hampshire,

00:16:00.000 | going through the snow, like trying to find our car, but we couldn't because it was buried in snow.

00:16:04.880 | And there was nothing in our ear and there was nothing to look at.

00:16:07.120 | You would just have to think.

00:16:07.920 | You were just thinking thoughts and mainly just, I'm cold.

00:16:10.480 | And why didn't I go to school at Pepperdine?

00:16:13.040 | But you were thinking.

00:16:14.880 | And then you would go and you would trudge through this to a library and you're just

00:16:17.600 | stuck there with your book.

00:16:18.640 | And you would sit there and have to like read your books for a while.

00:16:21.040 | We didn't have to think about it.

00:16:21.920 | We were like the farmers in the 40s.

00:16:23.360 | Now, 2025, you got to exercise.

00:16:25.760 | So you got to like force yourself to read books.

00:16:27.520 | You got to go for reflection walks.

00:16:29.200 | So cool article, scary trend, but at least on the individual level, I think it's reversible.

00:16:36.560 | When you read articles on a desktop or like a laptop, what do you do if you get distracted?

00:16:43.200 | Just put stuff in the working memory?

00:16:44.640 | So you put like, what are you talking about?

00:16:47.680 | Like if a thought comes up that's unrelated to the article.

00:16:50.080 | Yeah.

00:16:50.400 | That's trying to distract me.

00:16:51.280 | So you're not on your phone, but you're on a laptop or a desktop.

00:16:54.960 | I guess I would put it in working memory.

00:16:56.560 | I don't know.

00:16:56.880 | I'm pretty used to now when I'm doing something, I lock in on that thing.

00:17:00.560 | And then when I'm done, like now, what do I want to think about?

00:17:02.720 | But do you ever just read articles on a desktop or a laptop?

00:17:06.400 | Yeah, sometimes.

00:17:07.600 | Like, so I'm trying to think, it's a good question.

00:17:09.200 | Like this morning, I read articles from both the New York Times and the New Yorker.

00:17:13.120 | And in both cases, I use the app.

00:17:15.600 | On what type of device?

00:17:17.600 | On my phone.

00:17:18.480 | On your phone.

00:17:19.200 | Yeah.

00:17:19.920 | I'll also read articles on the browser and I'll print articles.

00:17:24.400 | It's like another thing I like to do, but I'm not very distracted by the web.

00:17:28.880 | You know, like I don't really have places to go to distract me.

00:17:31.200 | Yeah.

00:17:31.680 | Like maybe MLB trade rumors, but that's only relevant for like a three month period each year.

00:17:36.080 | So it's easier for me to just read an article and then I'm done reading that article.

00:17:40.160 | Right.

00:17:40.400 | Yeah.

00:17:40.640 | Hey, if you like this video, I think you'll really like this one as well.

Overstimulation Makes You Dumber | Cal Newport

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