Something You Should Know - What Algorithms Really Know About You & The Awesome Power of Doing Nothing

Episode Date: August 14, 2025

What if starting your meal with a mediocre appetizer could actually make the main course taste better? In this surprising opening segment, we dive into the psychology of taste and explore clever, science-backed tricks to make your food taste better — using your brain, not just your palate. https://www.dailymail.co.uk/sciencetech/article-3139067/ We’re all being influenced by algorithms every day — from what we watch and buy to what we believe. But what exactly is an algorithm, how does it work, and can you fight back against its invisible influence? Math professor and author Noah Giansiracusa breaks it all down and shares practical ways to take back control from the algorithms quietly shaping your life. Noah is an associate professor of mathematics at Bentley University whose work has appeared in Scientific American, Time, Wired, Slate, and the Washington Post. He is author of the book Robin Hood Math: Take Control of the Algorithms That Run Your Life (https://amzn.to/3U66fnt). Hard work gets all the glory — but rest may be just as essential. Neuroscientist Joseph Jebelli reveals how letting your brain idle can improve creativity, memory, and emotional health. Joseph is the author of the book The Brain at Rest (https://amzn.to/458OlWb). This conversation might just convince you that doing nothing is actually one of the healthiest things you can do. Think you lose most of your body heat through your head? Believe urine is sterile? Think again. In this quick and eye-opening segment, we bust some of the most common — and most stubborn — myths about your body that many people still believe. https://www.menshealth.com/health/a19547125/lies-about-your-body/?cid=isynd_PV_0615 Learn more about your ad choices. Visit megaphone.fm/adchoices

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That's code happy me at happy mammoth.com for 15% off your entire first order. Today on something you should know, how to season your food with sound, so it tastes even better. Then we know companies use algorithms to collect data about you, but how does it work? Because it sure can feel creepy. Well, I was, you know, saying something on the phone and then went on TikTok and I saw a video that was about the exact same topic. Does that mean TikTok is listening to my phone? And all I can answer is, I don't know. Technologically, that is absolutely possible, but we don't know which companies do it when.

Also, some interesting myths about the human body and hard work. You need it to succeed, but doing nothing and resting is also important. When we rest, we now know that our brain activates a network. And that network has been shown now to improve your intelligence, creativity, memory, problem-solving abilities, and so much more. All this today on Something You Should Know. Hi, I'm Adam Gidwitz, host of Grimm, Grimmer, Grimmist. On every episode, we tell a grim fairy tale. Not the cute, sweet versions of the fairy tales that your children have heard so many times.

No, we tell the real grim fairy tales. They're funny. They're weird. Sometimes they're a little bit scary. But don't worry. We rate every episode, Grim, Grimmer, or Grimmist. So you, your child, your family can choose the episode that's the right level of scary for you. Tune in to Grim, Grimmer, Grimmist, and our new season, available now. Something You Should Know. Fascinating Intel. The world's top experts. And practical advice you can use in your life.

Today, Something You Should Know with Mike Carruthers. So there's actually ways that you could make your food taste better or worse that has nothing to do with the food. Hi and welcome to something you should know. Some interesting research suggests that your appetizer can impact how much people like the entree. A study of diners conducted by Drexel University found that when people start their meal, with a really good appetizer, they enjoy the main course less. But when people have a lousy appetizer, they enjoy the main course more. It appears that our experience of food is done in context.

We compare one dish to the next. Another study done at Oxford showed that you can sonically season your food. In other words, the type of music you listen to while you're eating has an effect on how it tastes. Specifically, listening to music from the same country as your food enhances the flavor. The findings also suggest that slow music played while eating causes flavor sensations to last longer, but up-tempo tunes cause flavors to diminish faster on the palate. And that is something you should know. If you've ever thought to yourself,

I wish something you should know had an ad-free version, like some other podcasts. Well, now we do. People have asked and we're responding. You can now listen to all of the episodes without ads. Plus, you get exclusive premium content as well for just $3.99 a month, even less with an annual subscription. So check out the details at sysk Premium.com. The link is also in the show notes. That's SYSK Premium for ad-free listening and exclusive content. It seems like every day you hear about how you're being targeted by algorithms, that companies are using algorithms to do any number of things, to get you to buy something, to get you to vote for someone, to get you to scroll on your phone longer,

to somehow manipulate your behavior to do something you might not otherwise do. But how does it work? What exactly is an algorithm? Where does it live? What does it look like? How does it function? And does knowing all this help protect you from its influence? As much as we hear about algorithms, I sense a lot of us don't really understand the inner workings of them, which is what we're about to discuss with Noah John Syracusa. He's an associate professor of mathematics at Bentley University and a visiting scholar at Harvard.

His writings have appeared in Scientific American, Time, Wired, Scyracuse. Slate and the Washington Post. He's author of a book called Robin Hood Math, Take Control of the Algorithms that Run Your Life. Hi, Noah, welcome to something you should know. Thanks for having me. So everyone's heard what I just said, which is that companies use algorithms to target us and influence our behavior. But can you explain it better than that? Because, you know, we all have a general sense of what that might mean, but take it further. Yeah. I think it's easy to think, oh, when I go on Google, there's an algorithm there. When I go on Instagram or TikTok, there's an algorithm there because we hear about those algorithms. But I mean everything. When you go to apply for a bank loan, when you apply for college, when you look at college rankings in these magazines like US News, there's just algorithms everywhere. And that's because an algorithm isn't inherently a computer thing. It's really a mathy thing. An algorithm is just a process for kind of combining numbers in a certain way that ends up being for people. And can you explain what that means? Because when somebody says there's an algorithm,

I wouldn't know an algorithm if it hit me in the face. What does it look like? What is it, how does it function? Can you, in the simple way, explain that or is it too complicated? No, not too complicated at all. And that's because that's kind of a point I want to make is we think algorithms are too complicated to, not just to describe, but even to just think about what they are, but they can be anything and they can be everything. So when you get in your car, and you want to drive to your local grocery store. You probably have an algorithm in mind. Oh, if it's not rush hour, then I'll go this route.

But if there's a lot of traffic, it's better to go this other route. That's an algorithm right there. It's just kind of a little flow chart or a recipe that you're playing through in your head. The mechanics of driving, knowing that when I make a right turn, I'm going to lift my right arm up and turn the turn signal. Knowing when I can turn, I'm going to wait and look and see if there's cars coming. Your head is actually playing all these algorithms all the time. you're just not conscious of it.

But those algorithms are very similar in a way to what computers are doing. On computers, we just had to have people sit down and codify all those steps that we as humans do more naturally and intuitively. Well, we do it naturally, but not completely naturally. We do it based on prior experience.

We don't know how to turn a car until we do it and learn it and then remember it. That's right. And that's where we are in the history of computing. We use data and prior information or, to put it simply, we learn, exactly as you're saying, Mike, we're not born knowing how to drive a car, we learn how to do it, someone teaches us, we practice it, maybe we'll watch others drive a car, and we eventually are able to do it ourselves. And that's where computers are.

If you go back 15 years ago, 20 years ago, everything was written one line at a time in computer code to get computers to do what we want. But now we're moving into this era of AI, which is a lot more like humans and that AI systems learn as well. well through data through experience through interactions so when people talk about how corporations are using algorithms to track you and to know what you do and what you buy there's also there's a there's a sinister tone often in that that that that's is somehow this is evil is it evil i would say it's it's neutral with the potential for both good and evil but you're you're moving us in the direction i really want to go which is these algorithms

tend to be more than evil or good or bad or anything, they tend to be powerful. So why is that? Why are algorithms so powerful? If we're doing them in our head all the time, if computers have been doing them and they're still doing them, what makes them so powerful? Well, one thing is there's so much data available that they can find patterns and harness this data at a scale that no human could and no computer could 20 years ago. So there's a lot to work with in that learning process. So if you're thinking of targeting ads, for instance, that you mentioned earlier, the algorithms that we encounter when we go on the internet have just an unbelievable amount of data that they can use to try to target us.

And if you think of the directions we're heading, things like chatbots, all these long personal conversations that we're all having with these chatbots, just imagine how helpful that would be to an algorithm that wants to target us with ads. It doesn't have to just use our likes on Facebook anymore or our searches in Google. It can really use our intimate conversations. So that's one reason. These algorithms have a lot of data to access. They have a lot more computational power than they used to.

But a lot of times, it's just really how they're deployed. If you think of these tech companies, a lot of the social media platforms and search algorithms and things, search companies like Google, they might have a billion or two billion users. That's just an unbelievable scale. So when you're applying one single algorithm to one or two billion users, it doesn't really matter if that algorithm's good or evil. it's just powerful.

And that's where we get into some of the sinister that you're mentioning. Just the slightest tweak to some of these algorithms can really shift the balance of whether they're having a net positive or negative impact, who they're impacting positively negatively negatively. So I would say it's really the power that's important rather than the good or evilness of them. You mentioned a moment ago that some of us are having long conversations with chatbots. And not everybody's familiar with the term chatbot. and that not everybody uses them.

So explain what you mean by conversations with chatbots. Okay, so I also don't use these much, but a lot of people do. So I read about people who do, and my wife has gotten kind of sucked into these things. And people are treating these chatbots like Open AIs and Googles and Anthropics. They're using them for many, many things to help them code, to help them come up with shopping lists, to help them organize their life, organize their email. but there's also a lot of use as a kind of companion where you can really almost befriend the AI chatbot

and really talk to it and engage. But what's interesting is those are not very distinct uses. They're kind of blurred because of what we hit on earlier this amount of data. So if I want, for instance, a chat pot to help me write my emails, the more it knows about me, the better it can simulate my voice and write authentic sounding emails. Well, how's it going to get to know me?

You know, if I was a famous author, I could just say, read my books, but even that's not really me, you know, those are the books. But if I just talk to these chatbots a lot, as a lot of people are doing, then the chatbot really learns how the person thinks and interacts and behaves, and it can kind of harness that and put it into its emails. So this distinction between a companion and a sort of workplace assistant, there's a blurry boundary there. And because of the need for data, I understand why there's that blurry boundary. but it's just making a lot of opportunity for the kinds of surveillance and things that you mentioned. So when I use AI, I use either OpenAI or Chat, GPT. Sometimes I'll say I'm doing an episode of the podcast and I can't think of a really good title. So I'll ask and I usually, I'll say, give me 10 alternate titles.

Here's what the show's about. And I usually get 10 pretty good titles in one of which I probably will use. So that information, that conversation, is being put somewhere that it could potentially be used for something else. Yeah, I think he hit the right word was potentially. I don't want to go on the air and publicly claim that, you know, Open AI saves all this and uses it for advertising and Anthropic doesn't or Google does or does. All these things could happen. And that's kind of where we were with social media for many years. we just slowly over the 2000s started to realize this stuff is really cool, really powerful,

but it's a little bit creepy. And we started to recognize a lot of the sinister aspects you were mentioning. And it got to be a point where we just don't know and a lot of what these things could do and how they're used. And that's because there's a lot of lack of transparency. So one of the most common questions I get when I talk about social media algorithms is do they listen to you? So I talk about how these algorithms are using our likes and our comments and our shares and all these things. But people in the audience will always have this example.

Well, I was saying something on the phone and then I went on TikTok and I saw a video that was about the exact same topic. Does that mean TikTok is listening to my phone? And all I can answer is I don't know. Technologically, that is absolutely possible. So to put it in your words, Mike, these things are very much, there's a potential for this to happen, but we don't know which companies do it, when, because they're very opaque. We're trying to get a better understanding of algorithms and how they affect us. My guest is Noah John Syracusa, author of the book Robin Hood Math, take control of the algorithms that run your life.

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So, Noah, I'm sure that Mark Zuckerberg or Elon Musk or, you know, people at Google, they must be asked like, what's going on here? What are you doing? How is this data being used? What do they say? I think for the most part they deny. Sometimes they hedge and kind of, you know, answer a different question than it was asked. I don't know any instances where they admit it directly, but there's broadly just kind of

these companies give as little transparency as possible. There's like minimal legally required. Like in Europe, there's a bit more transparency required, so they'll do that in some states. But they kind of tell us as little as they need to in many respects. So what do we do with this information? What do we mere mortals? What do we do? So let me just give you a couple examples.

I think, you know, help our listeners to just be really concrete. So one is these social media algorithms, these mysterious things that have these sort of godlike powers to understand what we've been doing and what we're interested in, what we want to see, take something like TikTok. So how does TikTok's algorithm work? By that, I mean, TikTok uses some computer process based on data and all this stuff, some, you know, some algorithm, whatever that means, to give me a feed of videos. So when I go on TikTok, I'll see a video, and then I swipe, I see another one, another one, another one. And if you went on TikTok, you'd see a sequence of videos, and they'd be different than mine.

So how is TikTok deciding which videos I should see and which videos you should see? I thought this is some very complicated thing that we have no chance of grasping until it turns out in 2021, the New York Times got a hold of this document that was used primarily to train employees within TikTok who were more like the sales and other teams, so not on the engineering team, but it was written by the engineers. that was just trying to explain so everyone in the company had a general sense of how the algorithm works. They explained a bit about the algorithm. And it's frustrating because this was an internal document.

Why couldn't they explain to all of society what was in there, how the broad structure of how the algorithm works? Well, luckily, it was leaked by the New York Times, and I was able to take a look at passages of it. And here's the basic idea. I go online, I log into TikTok, and there's all these billions of videos that could potentially be shown. TikTok uses some really fancy AI, and that's the part we don't know about, but we don't really need to know about, to estimate the probability that I will like a given video, and the probability that I will comment on that video.

And the number of seconds, it's expected or it's believed that I will watch this video. So just a few of these estimates, and each of these are all kinds of engagements. So liking, commenting, watch time, these are all forms of engagement. And what the algorithm does is it assigns a weight to each of these forms of engagement. So maybe a like is worth one point and a comment is worth 20 points. I'm just making it of those numbers because they didn't tell us, but something like that. And then there's a single formula that just takes the value of a like times the probability of a like, plus the value of a comment times the probability of a comment, plus the value of a second watched

times the expected number of seconds watched. So it just multiplies those things, adds a moment. up together and it gives you a score. And all the videos are scored this way and whatever videos get the highest score will rise to the top of your feed. To put it another way, their algorithm is just trying to find which video you're most likely to engage with, but there's multiple kinds of engagement. There's not just one engagement. There's liking and commenting and all these different things. On Facebook and Instagram, there's a whole bunch more. Well, okay, but that tells me how they do it, but so now what do I do with that? Yeah, so I think we don't have the power

to change the weights, how much a comment is worth or alike. But I think it just gives us a clear picture of how we can behave online to shape the platform or usage of the platform in a way that benefits us. So for instance, I might see some conspiracy theory video and I might be really annoyed and tempted to write a comment saying, this is bogus, don't fall for this. But if I think of the formula, I remember,

wait a minute, a comment of any kind, even trying to debunk the video, video, it's going to count as engagement. It's going to give that video more score. So I'm going to see more like it. And others are going to see more like it. So it's kind of being aware of that formula has helped me remember to be a little more careful with where I place comments and other things like that. If there's a video, I don't know, I've seen some videos on TikTok that things like say things like, you won't believe what that guy does at the end or you know, watch till the end. There's a big surprise. And I watched to the end and nothing really happens. And I used to think,

maybe I missed it. So I watched it a second time. Still don't see anything. Watch it a third time. Still don't see anything. But now I realize, no, those are just really blatant tricks to get me to watch the video two or three times. Because let's say it's a 10 second video. If they can kind of trick me into watching it three times, that's 30 seconds of watch time, which gets counted in this formula. So it's just made me be a little more cautious. I don't fall for clickbait as readily. I'm a little bit more careful with with how I spend my engagement, let's say. I don't just waste it on clickbait and bad stuff because it's very clear to me that doing that is just going to give me more of that

and it's going to make it more popular for others. So what I find in, so here, so I have a lot of questions about this, but here, the one thing that baffles me, the one thing that they can't seem to figure out, like you know when you're shopping for a sweater and you buy the sweater and you pay for it and you go back to what you were doing,

you get a million ads for that sweater. Well, why can't they figure out, I just bought it, stop trying to sell it to me, I already bought it. Yeah, I mean, so that's a great question. I'd be careful, there's not necessarily a they, you know, there's different companies. I would say TikTok has done a very good job of dealing with this issue in a different setting.

and YouTube even to some extent. So let me start with videos, then we'll circle back to shopping. If I watch one fishing video and the algorithm's trying to figure out what videos I'm interested in watching, the obvious thing is, oh, more fishing, right? I mean, you just watched one.

But the problem is, after you watch one fishing video, maybe you watch a second fishing video, you might be tired of it. You want something very different. So they can't just keep sending you the most similar videos, but if they send you to something completely different,

you may not be interested in it. So they've actually worked on coming up with algorithms that have a longer-term strategy. Like maybe they'll send you a shorter video that's on a slightly different topic that might bridge you over to a longer video that you end up watching. So there is a lot of kind of strategy involved in squeezing out more watchtime and views from users. One of the things I notice, and I don't spend all that much time looking, but like I'll look at, I'll be looking at videos online and I'll see like a comedian that I like, Nate Bargatz.

I enjoy him and there's lots of little clips on Facebook and TikTok of him. And so the more I watch him, the more of those I get. But then one day they just disappear. They're gone. Entirely. And then they may come back later, you know, like a week later or something. I'll start seeing them again. But I always wonder, like, well, why did they decide enough?

That's enough. That's enough Nate Bargatz for you. Now we're going to give you something else. Yeah, you know, I don't have the answer. I think it's a great question. My guess is that it's very much in the direction that you mentioned with sweaters, that they figured out if you watch one of his videos, you're probably going to watch more.

But after a certain number or a certain number of days, you might be kind of saturating and losing interest. so they might have kind of rigged the algorithm so that you're not going to keep watching it won't keep showing you as many but this goes back to the general principles you have really good questions about shopping algorithms about

these video algorithms about all these things why don't they just tell us more about the damn algorithms so we know what they're doing we all have these questions why don't we have the answers I find that frustrating I think math is a step in the right direction or can be but I'm with you This is a frustrating situation to be in, to have such an imbalance where they know everything about us and we know so little about them.

Well, the other thing, too, is that I've always wondered about is, so when I watch these videos, I can see, okay, well, I've looked online for this, or I've watched this video, or this kind of video before, you know, a cat video or a dog video, so now I'm getting more of them. But then they'll be something totally, seemingly totally random. And so they must like just throw stuff in every once in a while just to see, I wonder if he likes this. The two things. So one is they use a lot of information of what other users are watching. So what might seem random to you could be that a lot of users watch a Nate Bargatz video and then suddenly watch a cat video. And if they did that, then it has a reasonable guess that you're going. going to be interested in that.

So sometimes, yeah, you just, the data is out there, and it's not just restricted to you and your data. It's really using what other people have done and kind of projecting those pathways through this world of entertainment onto you. Well, you've certainly explained a lot about algorithms. Seems like there's a lot we still don't know that nobody seems to know and would be nice to know, but I understand it better. I've been talking with Noah John Syracusa, who is an associate professor of mathematics at Bentley University,

and he's author of a book called Robin Hood Math, Take Control of Algorithms that Run Your Life. And there's a link to that book in the show notes. Noah, thank you for explaining this. Thanks for having me. It's been fun. Do you love Disney? Then you are going to love our hit podcast, Disney Countdown. I'm Megan the Magical Millennial. And I'm the dapper Danielle. On every episode of our fun and family-friendly show, we count down our top 10 lists of all things Disney.

There is nothing we don't cover. We are famous for rabbit holes, Disney theme games, and fun facts you didn't know you needed, but you definitely need in your life. So if you're looking for a healthy dose of Disney Magic, check out Disney Countdown wherever you get your podcasts. When you're awake, you should be doing something. You should not be doing nothing. After all, idle hands are the devil's workshop. Being busy is important. It is valuable.

It is necessary. Doing nothing, that's a waste of time. It shows you're lazy. You're just wasting your life. Well, hold on a minute. Maybe not. Doing nothing may just be the perfect thing to do. Joseph Gavelli is a neuroscientist and author of the book, The Brain at Rest.

how the art and science of doing nothing can improve your life. And he is here to explain why always being busy is overrated and why doing nothing may be a better choice, at least some of the time. Hey Joseph, welcome to something you should know. Hi, Mike. Good to be with you. So briefly, make the case for doing nothing because that idea certainly doesn't ring right for many of us. How can doing nothing be a good idea when there's so much to do?

So basically, when it feels like you're doing nothing, your brain is actually doing a lot of something. And so our understanding of work and rest from a neuroscience perspective and indeed from other perspectives is completely upside down. Basically, when we rest, we now know that our brain activates a network that we call the default network. And that network has been shown now to improve your intelligence, creativity, memory, problem-solving abilities, and so much more. And so actually, the case I'm making is that we've all been working far too hard using our working brain, which uses what we call the executive network. And when we do that, we actually ignore the default network, the resting network, but that's the network that brings you so many

cognitive benefits. That's the network that leads to long-term productivity. And so really what this neuroscience is teaching us is that people often succeed in life, not despite their in activity, but because of it. And that's the message I want to try and get across to people. But of course, you can't do nothing forever. If you don't do something, your nothing doesn't do you any good. Yeah, exactly. So, but the interesting thing is that a mountain new research now shows that whether you're a doctor, a train driver, a student, whatever task you're performing, you'll perform better on that task if you rest beforehand precisely because you're activating your brain's default network. So they've done so many studies now where they take

like sort of two groups of people and this can be two groups of people trying to solve a really complex problem like groups of students or it can be two groups of like doctors and nurses and, you know, they ask one group to, like, sit down and work really hard and try and solve the problem or perform the task, and then they tell the other group just to go and chill out and relax and, you know, seemingly do nothing. And it's always the rest group that performs better on the task because they've got that resting brain activity, that default network busily churning over the problem, busily ramping up their creativity, which then allows them to be much better at the work they then need to do. And so that's, I'm not anti-ambition, I'm not anti-productivity, quite the

opposite. But, you know, we, we need to radically redress how we think about work and rest, because it's rest that's the driving force behind all the things that you want to achieve in your work. Well, it makes a lot of sense. And maybe that's why, at least for me, I find, that I do my best work. I'm a little more insightful. I'm a little better in the morning because I've rested all night than I am in the evening. It's interesting that the first thing in the morning, there's a phase when you just come between sleep and wakefulness that we call the hypnipompic phase. And, you know, you also have, people might be more familiar with the hypnagogic phase, which is the phase just between being alert and then going to sleep. And those phases, the hypnagogic and the hypnogic and the

at times a very strong default network activity. So that's another prime opportunity to not sit there scrolling on your phone, but just to let your mind wander, you know, just stare into space, just allow your brain true rest. And that's when ideas will start to flourish. So here's what I want to understand better, though, is, okay, so I have a big project to do. So I should rest, you're making the case,

that I should, there should be a period of rest before I solve this big problem I'm about to solve. How much? Do I go away for a month and rest? Or do I take a nap for 10 minutes and rest? Or is it somewhere in between? So, yeah, that's a really good question. So this is really interesting, like the temporal dynamics of rest and what effect that has on the brain. So initially, most of the studies suggested that basically 10 to 30 minutes of rest before you perform a task is going to have a really positive impact on your ability to perform that task. But then they did a very large meta-analysis looking at the entire field of problem solving. And they found that actually longer periods of rest between sort of four to eight hours and even longer can also have

a really beneficial impact on your ability to perform a task. So as a general rule, than the more time you can spend doing nothing, resting, the better it is for your brain. I mean, for a specific temporal dynamic, you can think of sleep, you can think of naps, for instance. Some really interesting research from University College London in the last couple of years showed that people who have a 30-minute nap have larger brains than people who don't.

And the difference was really significant. We're talking 15 cubic centimetres, which is, to put in context, that's the volume of a small plum. And so, you know, I want people to think about you know, the huge number of nerve cells and synapses and connections and cognitive abilities that's contained in the volume of a small plum. I mean, it's staggering. And that's just from a 30-minute nap every day. So, yeah, so small windows of rest, very beneficial. Longer ones also very beneficial. There was a really interesting study just to briefly mention as well,

where they took a group of businessmen from Tokyo, people that overworked, and they went camping for three days. And because of that rest for their brain, and because of their exposure to nature as well, and we know that nature and green spaces are really, really good for the resting brain, they had a huge impact on their immune system, which lasted for a month after they left the forest. And so, you know, again, as I say, as a general rule, the more time you can rest, the better, especially with our overworking culture that we have today. But even just short pockets of time, if you've got, you know, every hour,

try and have, you know, five, ten minutes rest where you're not on your phone, where you're just mind wandering, staring out the window, going for a walk in the park. Just even those little pockets of time will be really good for your resting brain. There must be a point of diminishing return. So you can't just rest and rest and rest. And at some point, you've got to go do something. And I find that if I'm resting or if I'm not doing the thing I'm preparing to do, I start to get antsy. I want to get to work. And I understand that. I mean, I'm a hard worker myself. You know, I of course understand this. So it's, I'm not saying that we, you know, shouldn't engage in work and meaningful work. And the point I'm making is that we need a lot more rest for our brains in our day to day life in order to achieve that work in a far more efficient and more productive way. I mean, so, you know, if you take, you could take like the, take the four day work week, which they try, which they did a huge try. of an Iceland as like one example, they found that productivity at worst, it stayed the same, but it actually also went up to quite a significant degree. So, you know, and that's a day of the

week, gone, but productivity went up for so many people. So the point I'm making is that, you know, even if you do feel sort of, you know, as you say, like antsy, like that's fine. Again, like, you know, I'm not saying don't work, but I'm just saying that we, we are, dramatically underestimating like how much of a driving force rest is for our ability to do our work really well. So maybe it's individual, but can you give me a sense of what the day looks like for somebody who does this really well? Is it all about if you get a good night sleep, you're good to go, you should have a nap twice a day, what does it look like? I just want people to, first of all, have far more breaks throughout the day. So every hour, don't just carry on

grinding out on like a focused task. Allow your brain that, you know, just like even just five minutes, just time to decompress. Just allow yourself to stare out, stare out to the window and mind wonder. And you know, we catch ourselves doing this and we stop because we think, well, that's daydreaming. That's the thing I was taught as a kid to basically not do. And as a result of that, we still think of mind wondering as, you know, sort of, you know, you know, indulgent and even irresponsible and something taking us away from our work. But do that, you know, take more breaks throughout the day to allow yourself time to mind wander. Crucially, get that brain enlarging 30 minute nap in every day, if you can. Find micro moments of play throughout the day. Do things like exercise

as well. Like exercise is a form of rest. It's known as active rest. Lots of the people I spoke to for the book said, you know, I feel really rested after I've gone for a 30-minute jog. And, you know, that's not surprising. When you exercise your brain, you know, it starts churning out molecules like brain-derived neurotrophic factor or BDNF, which is like fertilizer for your brain, really good for your brain cells. And, you know, a huge study recently showed that even gentle exercise, like 25 minutes a week, which is like four minutes a day, even that's enough to grow a beefier, chunkier brain and a chunkier default network. But then things like silence as well. It's quite important, it's more important than people realize, to find peace and quiet

in their working environment. Again, we know that peace and quiet is really good for the brain by stimulating BDNF and a whole host of other growth factors that are really good for your brain, and at the same time, persistent noise is really bad for the brain. But also, I mentioned it briefly, but green spaces and nature, a huge study recently looking at 20,000 people, showed that basically 20 minutes a day in a green space. It doesn't need to be a forest. You know, it can be, it can just be a park, you know, a small garden, something nearby. 20 minutes a day is what you really need to have a significant impact on your neurological and psychological health. And we know that because when you go into a green space, your brain waves actually shift from very busy and anxious beta waves

into much more calming, reflective and creative alpha waves. And it does that, we think. Because basically nature abounds with what psychologists call soft fascinations. And these are things that basically hold your attention in a very effortless way. So, you know, when you go to a beach and you look at the lapping of the oceans or you go to a forest and you listen to the rustling of the leaves, there's a reason that that holds your attention effortlessly. And it's very, very good for your brain. So you've mentioned a couple of times a phrase, and I don't know what it means, micro moments of play. An example of that would be what? It can be like a, Lighthearted play, sort of on the spot antics, just anything that you find playful, you know, like I so I spend time sort of like messing around my cats, you know, I mean, anything that you find playful basically is going to be, it's going to be good for the brain. We know that play has a really profound effect on learning and memory in particular by stimulating neuroplasticity. But now we also now know that it's particularly good at activating the default network and leading to increases in creativity and memory and all sorts of other things. And I

I say micro moments, again, I suppose, to try and create that philosophy of incorporating more rest into our day in a much more intentional way, I suppose is the word I'm looking for. It's about not feeling the productivity guilt that we all carry, where we, you know, we equate our value and our worth as human beings with our output. We are living in a culture that it's just working far too hard and we're not activating our resting brain by doing that. So, you know, micro moments of play but then micro moments of other forms of rest as well

just to sort of incorporate it more into your day to stay life. There are things people do, though, that seem like play, seem like rest, that maybe aren't. Things like, you know, scrolling through your phone. You know, take a break from work and go sit down and scroll through your phone and look at people's cat videos. So scrolling on the phone doesn't count.

Binge watching your favorite series on Netflix, I'm afraid, doesn't count. Anything that you feel you have to sort of lean into in a cognitive way that feels mentally tiring. Like that's your executive network. That's your working brain. And that's why it leads to cognitive fatigue. So it's things that feel like strenuous. You know, the things that feel relaxing and effortless. and the things that you know sometimes as I say you feel a bit guilty about doing like spending more time

you know staring staring into space that that's the time when you're when you're activating your default network so it seems from what you're saying the general advice is to just rest more and play more and perhaps work less but you'll get more done and maybe get it done better instead of doing what I used to do what many people still do which is sort of this very old-fashioned mentality of grinding it out, you know, 10, 12-hour days, you know, the harder I work, the more I'll achieve, the faster I run, you know, the quicker I'll get to where I want to go. That mentality is just not how our brains operate. You know, you will get more done. You will feel better. You'll notice that your memory is better. You'll notice that your creativity is better

and your ability to solve complex problems is better if you just allow yourself more time to rest. So you've talked about the cognitive price we pay for overwork and not resting enough. Talk about the psychological impact of all this. It starts off as a feeling of dissatisfaction, like you're not happy with your work, but it's a manageable feeling, so you just ignore it. That then moves to cynicism, where you basically no longer really care about your work, it's just your job, you've just got to do it. That moves on to dehumanization, which is a complete emotional hardening and a kind of detachment from your colleagues. And that's what then leads on to symptoms of anxiety and depression. And the really interesting thing about the

stages of overwork is that there are these really interesting longitudinal studies done in Sweden that showed that once overwork and burnout sets in with this mentality that you just described with, you know, someone saying, well, I'm not going to take 20 minutes to rest. I'm just going to power through. Once it sets in, it takes up to three years to recover. It takes up to three years for your brain to return to the baseline of its ability to to solve problems and for your memory to come back to the baseline. And so we don't even realize it. But because we're because we're working so hard, because we have this old fashioned mentality. When people do this, do they then come back to you and go, God, Joseph, this is incredible? Or do they, is it much more? Like, how do you

know it's working, how are you supposed to feel differently? Is it real, real obvious? Or is it more subtle than that? Well, it takes time. So when I moved from overworking to being much more intentional about rest, it, you know, it did take a period of time before I started to really feel the effects. So for me, I think it was a few months before I was starting to think, oh, actually, I'm a lot less anxious and I'm sleeping better and my memory is a bit better actually and you know I'm certainly able to to write and communicate much more fluidly than I was before I think you know because I had so much anxiety to do with to do with overworking but that you know that did take a few months which again isn't surprising just to bring it back to that you know the Swedish studies showing

that it takes up to three years to recover and so you know that will also be a large part of the reason that you might not be noticing the effects if you're someone who overworks. But, you know, if you did incorporate more rest into your life after a few months, your brain will be coming more back to baseline. And I suspect, obviously, we would need to test you, but I suspect you would then start to perform much better on cognitive tests of problem solving and memory and creativity and a whole bunch of other things. Okay, but are the results only discernible in cognitive tests, or do people say, wow, this is great? It's definitely also anecdotal as well. I've had loads of people say to me, I take work-life balance far more seriously than I used to. People

have said to me, like, I do feel better, and I do feel better able to do my work, and I feel sharper, and my memories improved. Lots of people said that to me, which is not that many people, because most people I speak to say they're overworked, which is, you know, again, not. surprising when you look at all the statistics. But absolutely. As soon as people who start to take their work-life balance much more seriously and start to incorporate intentional rest into their life in a much more meaningful way do feel the benefits. Great. Well, we've just done a segment about nothing. Who knew nothing could be so important? I've been speaking with Joseph Jabelli. He is a neuroscientist and he's author of the book The Brain at Rest, how the art and science of doing

nothing can improve your life. And there's a link to that book at Amazon in the show notes. Joseph, I appreciate you coming by. Oh, thank you so much, Mike. There are some things about the human body that I know you've heard, you may possibly believe,

but these things are absolutely not true. First of all, that you lose most of your body heat through your head. Actually, the more exposed skin, the quicker you cool down. Heat exits all areas of the body equally when it's uncovered. It's all about the amount of exposed surface area, not body parts.

It's bad to wake up a sleepwalker. There's no evidence of that. There's no record that anyone has had a stroke or a heart attack or any other negative outcome from being awakened while sleepwalking. In fact, since sleepwalkers aren't aware of their actions, sometimes waking them up can prevent them from falling or otherwise hurting themselves. You only use 10% of your brain. This probably first came out of the mouth of a motivational speaker, but it is nonsense.

Brain scans reveal that nearly all of your brain is working almost all of the time. And you've probably heard that human urine is sterile. But human urine has at least 85 different bacteria in it. And that is something you should know. Our incredible crew includes Jennifer Brennan and Jeff Havison. They are our producers, our executive producers, Ken Williams. I'm Mike Rothers. Thanks for listening today to Something You Should Know.

Hey, it's Hillary Frank from The Longest Shortest Time, an award-winning podcast about parenthood and reproductive health. There is so much going on right now in the world of reproductive health, and we're covering it all. Birth control, pregnancy, gender, bodily autonomy, menopause, consent, sperm. So many stories about sperm. And, of course, the joys and absurdities of raising kids of all ages. If you're new to the show, check out an episode called The Staircase.

It's a personal story of mine about trying to get my kids school to teach sex ed. Spoiler, I get it to happen, but not at all in the way that I wanted. We also talk to plenty of non-parents, so you don't have to be a parent to listen. If you like surprising, funny, poignant stories about human relationships and, you know, periods, the longest shortest time is for you. Find us in any podcast app or at longest shortest time.com.