Freakonomics Radio - 439. Please Get Your Noise Out of My Ears

Episode Date: November 12, 2020

The modern world overwhelms us with sounds we didn’t ask for, like car alarms and cell-phone “halfalogues.” What does all this noise cost us in terms of productivity, health, and basic sanity?

Humans and animals have evolved in environments that have a lot of noise. We have noise from rain, we have noise from thunder, we have noise from other animals like birdsong, or crickets chirping. But human industrial activities also have introduced a lot of noise that are quite different from the sounds that we and other animals have evolved to live with. Peter Tyack, T-Y-A-C-K,

is a behavioral ecologist at the University of St. Andrews in Scotland. And I've studied the sounds of mainly marine mammals, and that's given me an entry point to understanding how sound travels in the ocean, which is quite different from what we're used to on land. Different how? We, as terrestrial mammals, are used to vision being the great distant sense. We can see things from very far away, much further than we can hear.

But if you've snorkeled in the ocean, you know you can only see about 10 meters, something like that. But you can hear much further away. So the key difference between life on land and life underwater is that for a mammal that wants to understand what's far away, they really need to rely on sound in the ocean. Sound in the ocean, therefore, exerts a lot of leverage. Sometimes, this is good news. Consider a recent experiment by scientists working at the Great Barrier Reef off of Australia. When a coral reef is healthy, it is quite noisy with the sound of marine activity,

and that noise attracts more activity. But a patch of coral reef that is dead or dying is quiet. So the scientists went to these quiet patches and placed speakers underwater to play the sounds of a noisy reef. It seems to have worked, attracting lots of fish who stayed on. Here's how the researchers put it. Acoustic enrichment shows promise as a novel tool for the active management of degraded coral reefs. So there are beneficial ocean sounds and the opposite. Peter Tyak was once studying whales in the Bay of Fundy off the Canadian coast. It was generally a good place for whales to be with lots of appetizing food.

But there also are shipping channels near there. As part of his research, Tayak recorded the calls the whales make. But always in the background was the sound of shipping noise. Researchers like Tayak had never really thought much about this background noise. It was just there. But then, all of a sudden, it wasn't. The change came with the 9-11 terrorist attacks. All of a sudden, the ships that were plying the ocean in that area stopped.

This drop in ship traffic was only temporary. But it happened to coincide with some other whale research that was happening in the Bay of Fundy. Researchers from the New England Aquarium had been sampling feces from whales to look at stress hormones. It wasn't part of a noise experiment at all. It was just, you know, your standard whale feces research. But what they found was that if you compared the stress hormones in whales before 9-11 and after 9-11, their stress hormones actually went down after 9-11. I am guessing you did not wake up this morning thinking you'd be hearing about whale feces and stress hormones. But noise? You probably think about noise all the time.

I know I do. Especially as the pandemic has rearranged our world, our routines, our soundscapes. Think how hard it can be to control the background noise in these new settings, especially when someone else is generating the noise. If whales are stressed out by noise, how about you? Before we answer that question, let's gather some more whale evidence. Peter Tyak told us about another type of whale. A very poorly known set of toothed whales called beaked whales. When U.S. Navy ships in the Bahamas ran exercises using sonar,

that's sound navigation and ranging, which emits bursts of underwater sound, these beaked whales had trouble. Over a period of a few hours, whales would strand by ones and twos over tens of kilometers of beach. Tayak and his colleagues wanted to learn just how sensitive the whales were to these sounds, so they developed tags to track the whales' behavior, and then dropped speakers in the water to play their own sonar noise, first at very low levels. What we found was that at quite low levels of exposure, much lower than the levels that

actually cause hearing damage, the animals would stop making their echolocation clicks, they'd stop foraging, and they would then do a very long, slow ascent to the surface. This surfacing is unhealthy for the whales. It may cause an explosive decompression syndrome in which they get gas bubbles in their body, like a diver with the bends, that could even cause animals to die at sea. Or they may panic and strand on shore.

Why would the whales have such a drastic reaction to such low levels of sound? This is something that's seen in a lot of wildlife, that if they interpret a sound as a threat, they've evolved anti-predator responses, and these may cause them to show pretty strong responses at relatively low levels of sound. The science shows that most humans are not nearly as sensitive to sound as whales. Still, you have to consider what kind of responses we are having, knowingly or unknowingly, to all the noise around us, even if it doesn't seem particularly noisy.

We're just used to the baseline of the ambient noise around us. So if you grow up in New York, your baseline is the sounds of planes flying overhead and fire engines going by, and that's something that you don't really pay attention to. Most guidelines say that sounds above 85 decibels are physically harmful, but think of all the baseline sounds we barely notice. Normal breathing is around 10 decibels. A computer fan, 20. The hum of a refrigerator is around 40 decibels.

A dishwasher, 75. A window air conditioner, more than 80. And then there's the drive-by DJs, the renegade fireworks that punctuated New York City during the pandemic this summer, usually late at night, and of course, the quintessential 21st century sound. What'd she say? She said, what?

I can't believe it. She would say one-sided cell phone call. I mean, seriously. Today on Freakonomics Radio, the economics of noise? One very economics-y thing that I worry about is that noise is very susceptible to a race to the bottom. How people suffer from noise? He said, I'm not afraid of sound. Sound is making me upset. And what can be done about it?

One word, and that's the word called respect. Sound is making me upset. And what can be done about it? One word, and that's the word called respect. From Stitcher and Dubner Productions, this is Freakonomics Radio, the podcast that explores the hidden side of everything. Here's your host, Stephen Dubner. Here's a question to start with. What is particular about sound? Sound doesn't respect barriers very well. As many people have pointed out, there are no ear lids.

That's Mac Haygood. He is a scholar of sound at Miami University in Ohio and the author of a book called Hush, Media and Sonic Self-Control. Sound has always been a challenge to our sense of autonomy. Emphasis on the always. We can look back at the famous Stoic Seneca back in ancient Rome, who wrote that if you were truly in control of your own consciousness and emotions, then you should be able to withstand any sort of sound. And yet, eventually, Seneca moved out of Rome to the Roman suburbs because he couldn't stand the noise anymore. Noise like carpenters at work and musicians in the public square.

So I kind of picture he's moved out by Ikea. The philosopher Arthur Schopenhauer, writing in 19th century Germany, complained that the cracking of horse whips paralyzes the brain and murders thought. I submit that if people like Schopenhauer and Seneca considered noise worthy of their attention and disdain, we may follow suit. Absolutely. And sound has changed a lot in modernity and the world has gotten noisier. So we have new kinds of factory noise. We have new kinds of noise from transportation, railways, automobiles, airplanes. And then we have new kinds of ways of consuming sound itself through the radio. Kept you awake, but now pleasant dreams and be with us again tomorrow night. Through the television. I'm Oprah Winfrey and welcome to the very first National Oprah Winfrey Show! And through podcasts, of course.

You have chosen to put the sound of my voice in your ear. Why? I cannot say, but you have. On the other hand, we are also becoming more finicky when it comes to sound. Some people, for instance, seek out sounds that trigger what's called ASMR or Autonomous Sensory Meridian Response. That is a tingly, relaxing feeling some people get when listening to the sound of, say, a bar of soap being carved or typing on a keyboard. Plainly, the modern menu of sound is a vast, all-you-can-eat buffet. But just as plainly, many sounds are thrust upon us, which has had significant consequences. We've got new diagnoses that have popped up that just never existed before. Hyperacusis, for instance, a rare but debilitating sensitivity to certain frequencies and ranges of

sound. Or phonophobia, a fear of sound. And then there's misophonia, a condition that was identified relatively recently. The name means hatred of sound, although the man who named misophonia admits the name is imperfect. Misophonia, God forbid, should not be translated literally as hate to sound. That is Pavel Yastrobov.

I would say like this. And that is his is Pavel Yastrobov. I would say like this. And that is his wife, Margaret Yastrobov. Misophonic reaction is negative reaction to specific sounds or sounds in very particular situation produced by one or two specific people or in specific situation. Okay, that's a little bit helpful. So misophonia is a negative reaction that certain people have to certain sounds in certain situations? Oh, it's a long story.

The Yastrobovs run the Yastrobov Hearing Disorders Foundation Clinic in Maryland. Before that, they were medical school professors at Emory University. Yes, still Professor Emeritus, which actually gives me a great privilege of having free parking. It was at their clinic that Margaret Yastrobov first noticed this interesting new condition. Some patients reported an extreme sensitivity to certain sounds. Typically, this would be diagnosed as phonophobia, a fear of sound. But that label was upsetting to these patients. Margaret recalls how one of them stormed out of the examination room.

He screamed at me and he said, I'm not afraid of sound. I'm not fearful. Sound is making me upset. I cannot control my reaction. The Ostroboths found there were a range of specific sounds that upset different patients. For example, sound of door closing or airplane flying or sound of eating or sound of kissing, for example, interesting case. Why would someone have no problem with most sounds but become distraught over the sound of eating or kissing? So we start thinking about this and we realize that it's not only fear, it is something definitely more complex. One of the most common misophonia triggers is the sound of chewing. You may dislike the sound of someone chewing their food, but for someone with misophonia, the sound is excruciating.

Where does this come from? What I believe, what I'm proposing, misophonia reflects subconscious connection. A subconscious connection with, in all likelihood, an unhappy event. Imagine you are a little kid at Sunday dinner with your whole family and your grandfather's dentures fall out onto the table. The feeling you had then, an icky feeling, could become subconsciously associated with the sound of anyone chewing, and it could subsequently generate an automatic physiological reaction. To treat patients with mesophonia, the Osterboffs have drawn on a method used to treat people with tinnitus, or as it's also pronounced, tinnitus. That is a disorder most of us think of as a ringing in the ears. But it's not necessarily ringing. It can be any kind of a sound. It can be

hissing, can be sound of insects, the sound people were hearing Christmas carols. Just to be clear, people with tinnitus hear these sounds when there are no actual Christmas carols or insects. Basically, it's the perceiving of a sound that is not created by hearing. So tinnitus is phantom auditory perception. Some people with tinnitus aren't particularly bothered by it. For others, it generates an intense emotional response. One treatment is called tinnitus retraining therapy, or TRT, which was developed by Pavel Yastrobov and a colleague, Jonathan Hazel. It is a combination of psychotherapy, including stress management and relaxation exercises,

and sound therapy, like using white noise to mask the tinnitus sound. So even if you are hearing the sound, this signal is not spreading to emotional system, it's not causing an emotion, and it's not causing any reaction. And this is the therapy the Yastrobovs have been trying with patients suffering from misophonia. They've had at least some success with about 80% of their patients,

and early clinical studies have shown promise. Even for the majority of us who don't suffer from something like misophonia or phonophobia, it's still easy, at least I'd argue it's easy, to appreciate that noise can generate strong emotions. Though not always in predictable ways. Just as one man's trash is another man's treasure, the scale of noise appreciation is a sliding scale. The very same chewing sound that may torment someone with misophonia can delight someone

who experiences ASMR. Your favorite song in the world might be my least favorite. You can tell a lot about how someone feels based on whether they describe something as sound or as noise. So the definitions of noise and sound are often debated in the field of sound studies. That, again, is Mac Higgins, the sound scholar, or maybe the noise scholar. When most people talk about noise, the argument is the world has gotten noisier and we need to do something about it, right? And it's true. Some of these sounds are objectively damaging to our

health, but history doesn't just change the sounds around us. It also reshapes how we define what's noise. History also reshapes the senses themselves. What actually sounds pleasing and displeasing to us? How we listen the telephone and headphones to listen closely and evaluate sounds in a particular way that's different from in the past. And so we have this new pressure to survive through our ability to concentrate. And that's when noise starts to seem like a real big problem. Here's one very reductive definition of sound versus noise. Sound is something I make or choose to hear. Noise is something you make or choose to hear.

This isn't a real definition. I just made it up, but I don't think it's all that wrong. If you look at surveys where people are asked what sounds I hate the most, the answers aren't very surprising. Loud interruptions like garbage trucks, sirens, and car alarms. Also snoring.

And loud phone conversations. Other people's loud conversations, of course, not our own. Our own noise rarely bothers us. This is good evidence that when a noise does bother us, it's not necessarily the sound waves themselves. It's what they represent or maybe fail to represent. Consider the one-sided cell phone call, or as it's been named, the half-a-log. Why is that so much more annoying than hearing two people talking? Some academic researchers asked that very question and came up with a plausible answer. When we hear just one side of conversation, our brains are compelled to fill in the missing information.

Imagine reading a book with every other page torn out. The cell phone half-a-log is noise we can't ignore. And because we can't ignore it or control it, we find, as Seneca wrote a couple thousand years ago, that our very autonomy has been challenged. Coming up after the break, just how costly is noise? The first experiment is really designed to answer this question of what is the impact of noise on productivity? And let's hear from someone who just gets it. If you are seeking assistance with a noise problem, you can contact me directly. I'm Stephen Dubner. This is Freakonomics Radio. Thanks for putting us in your ears. We'll be right back. When you think about sound and noise, it's easy to point out all the detriments.

But as with anything that exacts a cost, there are benefits as well, often massive ones. Consider all the music you love, the conversations you have, the pre-pandemic thrill of being in a big crowd during a celebration. We should also appreciate the strategic application of sound for the benefit of our species and other species. We already mentioned how scientists at the Great Barrier Reef drew fish back to dying reefs by playing audio of a healthy reef. And hear this. Scientists at the University of Washington recently began using ultrasound acoustic tweezers that can manipulate a kidney stone and help clear it through the urinary tract. That said, it is wise to be aware of the downsides of noise,

especially noise that we can't control. People have studied children, for example, in Munich, both in a place where there was an airport and where an airport was going to be built. That, again, is the behavioral ecologist Peter Tayak. And when they closed the old airport and moved to the new airport, the children in the new area all of a sudden had cognitive problems related to learning with language tasks. It wasn't loud enough to affect their hearing. It didn't affect their immediate health.

But there were problems with, say, in school, being able to understand complicated linguistic problems. Other research has found that airport noise has negative effects on various cognitive and physical dimensions, even after adjusting for socioeconomic factors and pollution. Other studies have looked at the noise generated by highways and subways. Let me talk about my work on subway noise. That is Arlene Bronzeft. Professor emerita of the City University of New York, and I do research and write on the effects of noise on people's mental and physical health. She is also on the board of a nonprofit called Grow NYC, which runs environmental programs in the city.

And we also have a section on noise in which we give advice to people on how to lessen the noise levels in their lives. But if you go to our noise site and you are seeking assistance with a noise problem, you can contact me directly. Now, you're not saying that you go down to 311 and take the calls. You're saying this is a separate channel. Actually, the people who contact us at GrowNYC have not been able to get the assistance through 311, through their public officials, with their managers of their buildings or their landlords. And I get the most difficult cases. Do people contact me?

The answer is yes. The board members of Grow NYC are appointed by the mayor. And to date, Bronsaft has made it through five of them. She is a legend in the world of noise research, but that was not her original plan. Noise found me. In the 1970s, Bronzaft was teaching environmental psychology at Lehman College in the Bronx. A student asked to speak to me after class and said, my child goes to a school next to an elevator train, and the noise from that train disrupts the classroom every four, four and a half minutes. And we intend to sue the city of New York in order to improve the education of our children

because we believe the train noise is disrupting their learning. To which I said, as the wife of an attorney, you need data to prove that the children aren't doing as well in that class. And she said, will you help us? This turned into Bronzaff's first study on the effects of noise at PS98 in Upper Manhattan. One side of the school building faced a nearby elevated subway. The other side faced away. Bronzaft matched second, fourth, and sixth grade classrooms on the quiet side and on the noisy side, where a passing train would push the sound readings from 59 decibels to 89 decibels.

Then she compared the average reading scores from the two sets of classrooms. And the children exposed to the transit noise were nearly a year behind in reading by the sixth grade, and the teacher had difficulty teaching. The published paper got a lot of attention. But I had not really responded to the mother's request. She asked me to help the children. And so I went back to the school, and with the aid of the principal, we went to the Board of Ed,

and we asked for acoustical ceilings in the classroom. And I was able to persuade the transit authority to choose the site adjacent to that school to test out a new procedure to quiet the noise on the tracks, and they agreed. And when I looked at the reading scores in the now quieter classroom and compared it to the reading scores of the children on the quiet side of the building. It turned out they now were the same. It's worth noting that Bronsaft's subway research, as with similar studies at airports and elsewhere, have some limitations. For one thing, Bronsaft couldn't randomly assign students to the noisy versus quieter classrooms.

There were also relatively few classrooms to choose from, so there might have been some natural variation. In any case, this kind of research led to Bronzaft becoming a scholar of both the physical and psychological aspects of this issue. Sound is a physical phenomenon. Noise is a psychological one. Sound comes into the ear, it travels to the brain, and it registers in the temporal lobe. And then we further identify what the sound is. But noise lets you know whether that sound is disturbing, is bothersome, is hurting you. And that's a psychological phenomenon. Which part disturbs us more about noise, the intrusion itself or the fact that in most cases we don't have an ability to control it? So I would say both. The actual sounds that you're hearing is disturbing your sleep.

And there's a phenomenon in psychology called learned helplessness. It means no matter how I try, I can't stop it. And that is also costly to one's health. Can you talk a bit more about any trade-offs you can think of in noise reduction? For instance, New York City subways are still, as far as I know, steel-wheeled, which are noisier than rubber. So then I get to thinking, well, you know, maybe steel wheels are safer or they're more durable or whatnot. But, you know, there's no such thing as a free lunch. I understand that companies, you know, are in business of making money. But what about the medical costs for people who live near noisy airports?

And the data have demonstrated increased cardiovascular disorders for people who live near airports. Doesn't that cost money? So if you ask me, do the companies that produce the noise through their products, through their activities, are they holding the upper hand? Yes. But we're paying for it because medical costs in this country are high. So are educational costs. Remember, if the children were a year behind in reading, how much would it have cost to remediate their learning deficits? In Bronsaft's work as an advocate for New York citizens, she has dealt with all sorts

of noise complaints. Among the most common are pervasive bass sounds. Yes. Are you in the mood to imitate a pervasive bass sound? You can do that better than I. I can speak to bass sounds. Would you please? Yes. If you live above a bar or a music establishment, you not only hear the bass, but if you're lying in bed, you will feel it. The bass sounds are low-frequency sounds. Usually, we talk about noise in the mid-range of the frequencies,

but when you talk about bass music, you're talking low. Bass sounds have taken more of a center stage today with wind turbine introduction, because wind turbines are now seen as an alternate source of energy. However, the wind turbines generate the low bass sounds. And the laws that have been passed to regulate the sound levels of wind turbines have been on the A scale, the mid-range, where we commonly measure the levels of sound. And they've sort of ignored the low bass. And so you find a great uproar from citizens living with turbines saying they don't want them. So let's pull back and get a sense of the overall societal costs of noise pollution.

What does the economics literature have to say about that? It really doesn't exist. That is Josh Dean. I'm an assistant professor of behavioral science at the University of Chicago's Booth School of Business. So economists really haven't calculated the costs of noise pollution? There's a very large history of psychologists using noise in laboratory experiments, both to understand the impacts of noise per se, but then also using noise as a kind of tool in order to understand other things like how our working memory works and how our attention works. But there's really nothing in economics, and there's really not much in terms of how this affects economic outcomes. I think I, in scouring the literature, managed to find three other papers that have looked at this question, including one from 1935 with 20 subjects. Dean scoured the literature because

he had become personally interested in the topic while working on a different project in India. I was living in Delhi and I was in a cafe trying to work as, you know, lots of grad students do. And I kept getting distracted by all of the horns honking and the people selling things. And I kind of had a light bulb moment where I realized, you know, if I'm having trouble doing this inside of this nice cafe, what is this like for people who have to live and work in this kind of noise without even the minimal escape that I'd been able to find? And when you think about noise as a research subject, what made you go to productivity versus, let's say, the health outcomes, physical or mental health outcomes or other potential downstream effects of noise? Some of it is just that you want something that is relatively easily measurable and quantifiable. And productivity is nice in that way. And it's

particularly nice in that you can put a dollar value on it. If you tell someone the noise in your factory is causing a 5% decrease in productivity, that means something to them in terms of making the decision of whether to abate noise. If you tell people something like 25% of your metal workers have disabling hearing loss, you have to take another step of trying to convince people that that means that you should care about this, right? And so productivity is an easier outcome both to study and to then use to persuade people to care about this, right? And so productivity is an easier outcome both to study and to then use to persuade people to care about the problem. Wow, that was a very compelling if depressing answer. Isn't that what economists are supposed to be good at?

So Josh Dean set out to personally expand the scant economics literature on noise and productivity. There were three research questions that I was interested in answering. The first is kind of, is there an effect of noise on productivity? Full stop, and if so, how big is that? In other words, you were not believing the 1935 paper. No, I would like some more robust evidence. And so that's the first goal. And then the second goal is to understand

what is the underlying mechanism by which noise affects productivity. There's this psychology literature that suggests possibly something like inhibiting attention or working memory, but it could also be something like reducing the effort of workers because they don't enjoy being put in noisy working conditions. And depending on what the mechanism is, that is going to lead to different conclusions about where we should expect this to matter and what the right policy response should be. And then the last question is to understand how much scope there is for workers to adapt to noise by doing things like purchasing hearing protection or avoiding noisy working conditions. How workers adapt to noise. That is something most of us struggle with at some point, especially if your work involves any cognitive tasks. Some of us struggle more than others, and I am raising my hand here. I have always been badly distracted by noise, even the casual background conversation that most people seem to power right through. When I first started working in newsrooms,

I wore foam earplugs all day, every day. And yes, I was ridiculed for it. Later came noise canceling headphones, a total godsend with the additional benefit of signaling to coworkers that you don't want to be interrupted. Noise canceling headphones have since increased in popularity, Thank you. It's an array of speakers that emit sound waves calculated to cancel out the incoming noise. So the appetite to mitigate the noise of modern civilization is plainly strong. As for the exact cost of all that noise, that is what Josh Dean wanted to figure out. So he set up a study with two main experiments. So the first experiment is really designed to answer this question of what is the impact of noise on productivity? And to do so, I recruit a group of manual laborers who are used to working in noisy factory conditions and bring them to a textile training facility. This facility was just outside of Nairobi, Kenya.

There were around 100 workers in the study, and they were being trained to sew pockets for clothing. And then while they're performing a kind of standard sewing task, I randomly exposed them to engine noise, which we think is representative of some of the major types of noise you might worry about, thinking loud industrial machines, think cars on the street. Significantly, engine noise also doesn't have any informational content. It is not like that one-sided cell phone call you're subconsciously trying to participate

in. It's not even like overhearing a TV or co-workers chatting. Now, you may be wondering how Dean was able to randomly expose these workers to engine noise. So what's nice about this training facility is that they also train automotive mechanics. And for that reason, they have car engines mounted on wheels. So I'm able to both randomly assign workers to rooms and then randomly assign which room is noisy. And what do you do about the exhaust? I assume you want to isolate the noise and not the air pollution?

Right. So we have the car engine out in an open courtyard with the exhaust pointing away from any access point to the room. And then to double check that none of the exhaust accidentally bleeds in, we measure the CO2 levels of the room. And then to double check that none of the exhaust accidentally bleeds in, we measure the CO2 levels of the room. How many decibels louder is the room with the engine than the quieter room? So it's seven decibels louder. Oh, that's not very much. Well, decibels are tricky to interpret, right? Because they're on a proportional scale. So three decibels is the detection threshold of human hearing, and a 10 decibel change is perceived as twice as loud by humans. So it's not very intuitive. I think the more intuitive way to think about it is if you go from having a kind of normal dishwasher going in the

background in the kind of control condition to having a vacuum cleaner right next to you. So these textile workers would spend a few days in training and then get randomly assigned to rotate through noisy and less noisy rooms. They were paid for each pocket they sewed as long as it was deemed acceptable by an impartial judge. After two weeks, Dean had enough data to see how the noise affected productivity. So what we find is that if we double how loud the room feels, the workers are about 5% less productive on this task. And just to put that number in perspective, we also randomly assigned how much we were paying participants based on their production. And there,

if we double their payment from 5 shillings per pocket to 10 shillings per pocket, that only increases productivity by around 3%. So if you had to describe the magnitude of this effect in lay terms, and since we're talking about clothing, let's put it in small, medium, large, or extra large, how would you describe the change in productivity then? I would say a medium-sized effect relative to the other means we know of affecting productivity. There's another great paper that looks at the effects of an intensive months-long management intervention in a textile factory in India. And what they find is that that increases output by 9%. And so this 5% effect is about in line with the other means that we have of affecting the productivity of workers, which suggests that it's an economically meaningful environmental input.

There was another tangential finding from this experiment that was of interest to Dean. When it came to being distracted by noise, it didn't seem to matter how good a given worker was at sewing pockets. In other words, a high level of skill didn't lessen the noise distraction. Right, exactly. If you have a distractor, you've got to slow down a bit to focus on what you're doing to make sure that you're doing it right. And that slowdown factor just appears to be constant. And then there was a second experiment within Dean's study. This one was meant to understand why productivity falls in noisy conditions. Was it about the cognitive strain, or perhaps due to decreased motivation or physical weariness? In this case, Dean ran a condensed

version of the first experiment, but rather than sewing pockets, the workers performed tasks that tested skills like attention and working memory, as measured against a placebo task that didn't involve any cognitive input at all. The result? Workers did slightly worse on the cognitive tests and slightly better on the placebo task. So what I think we learn from the two experiments is that noise can impact productivity and that this seems to come through this cognitive channel. So how much can you generalize or would you want to generalize these findings to productivity in other areas where noise is a factor. Let's say an open office with conversations

going on in the background or a hospital with dinging alarms and so on. There's two questions you have to ask yourself. The first is, how similar is the noise? And in particular, along those two dimensions of informational content and how constant the noise is. So if you are extrapolating to a setting like an open office, you could imagine that the effect would actually be much worse because the noise that you're being exposed to has informational content associated with it, right? So I'm working on selling a product or a spreadsheet and I hear the person in the cubicle right next to me talking about basically the same thing. That's much harder for our attention to filter. And then the other is

the task. This is why it's important to know that the mechanism really does appear to be impairing things like attention and working memory because that lets us think about the fact that the places we should expect this effect to show up are tasks that have demands on attention. I just wanted you to talk for a moment about noise or noise pollution as what an economist would, I assume, call a negative externality. Yes, this is something that I have to put up with that I am not causing, and yet the person that's producing it is not paying a price. So can you just draw that scenario for me and how you think about it as an economist in the modern world that's producing a lot of noise?

Sure. I think actually we don't have to just even think about the modern world. There's this great book on the history of noise by Goldsmith, And he talks about the first noise pollution ordinance to manage this externality where I'm creating noises that are beneficial to me, but bother all of the people around me dates back to the 6th century BCE. No joke. It is a Greek colony, and they had such a problem with their potters and tinsmiths and tradesmen making noise and bothering people that they banned them from working in the city. Another example that I really like is in 1787, when the founding fathers were working in the Pennsylvania State House on the Constitution, they apparently spread dirt on the cobblestone streets outside in order to prevent themselves from being distracted. So I think noise is one of the oldest externalities that we've had to deal with,

and it is a natural byproduct of a lot of things that you want to do. It's a byproduct of getting around. It's a byproduct of making things. It's a byproduct of entertainment, and just by its very physical nature, affects everyone who's around you, and it's something that you don't really think about or you don't fully appreciate the impact that it has on other people. And it's a problem governments and those who try to manage externalities have been dealing with literally since ancient times.

The US used to have a Federal Office of Noise Abatement and Control as part of the EPA, but it was defunded in the early 1980s, which shifted responsibilities to state and local governments. So there are rules on the books in most places that limit, for instance, when construction can happen and how loud it can be. Same for garbage trucks and bars and even personal lawnmowers. There are even prohibitions against ice cream trucks playing their jingle once they're parked at the curb. But of course, there is a big difference between having a noise code and enforcing it. In New York City, between 2010 and 2015, there were about 1.6 million noise calls via the 311 complaint line. Only 1% of the cases where the NYPD confirmed noise resulted in a summons.

Josh Dean again. means that in order to compensate, I have to get louder, which then makes you get louder. Some car manufacturers in India have recently started advertising that they can make their car horns extra loud for you. There's no intrinsic reason you need a really loud car horn, right? You have a really loud car horn because everybody else has loud car horns. And this kind of strategic interplay means that you can get noise levels that really quickly spiral out of control. Fighting sound with sound is what I see people doing with these different kinds of technologies, sort of pacifying the space around them in order to maintain their own control of their own attention and their own state of mind. That, again, is the sound and noise scholar Mac Haygood.

His concern about a race to the bottom isn't so much that the world will get unbearably loud, it's that we will focus on individual behavioral problems at the expense of wider structural solutions. I mean, is it your jerk co coworker who slurps ramen noodles? Are they the problem or is it the open plan office that someone decided was a lot cheaper and more efficient to design? Have we fallen into certain patterns where we're so used to controlling the sounds around us that we don't think to take off the headphones. And this is the real problem is there can never be enough control. The more control we get, the more sensitive we become to noise. And if we could

magically wipe out all the sound in the world, then we would hear the sound of our own tinnitus because tinnitus gets louder in a vacuum. So I think we just need to think about this path because I do not think happiness lies in that direction. In which direction does happiness lie? You will find that one word would really cut back on noise intrusion, and that's the word respect. And that, again, is the noise whisperer Arlene Bronsaft. I think if respect came back and people understood that their sounds can intrude on the lives of others, I think the 311 calls would drop drastically. To be clear, Bronsaft is not advocating

for silence or anything close to it. Even though I write a great deal about noise and speak about it, I am trying to say to people, listen, there's such good sounds out there.

Although many of these good sounds can't fully return until the pandemic subsides, especially in such a naturally noisy and crowded place as New York. I do not want the children cheering on the Macy's Day parade to stop cheering them on. When the ball falls on New Year's Eve, I want the people to shout out and enjoy the moment. I'm not asking for the music venues to shut down. I'm not. I think the vibrancy of the city, the parade, the ball falling, the music that we hear in our city, these are all positive things.

So let's not lose sight of the various wonderful sounds the city does have. Just tune down the ones that are intrusive and harmful to our health. Coming up next time on Freakonomics Radio. In the U.S. alone, we spend more than $250 billion a year on advertising. Just think of how many ads you've seen over your lifetime for products like Coke and Dove and Ford. So we have to assume that advertising works, right? The fact that Coke and Dove and Ford have been around for decades suggests that maybe advertising does work. That's what you hear at least from the advertising industry. So what's the evidence?

Oh, ads definitely work, but we can't tell you how or why or give you any evidence for it. Could it be that many, even most of those billions of ad dollars are being wasted? It does, in fact, look like many advertisers in our data are over-advertising. It's next week on Freakonomics Radio. Until then, take care of yourself and, if you can, someone else too. Freakonomics Radio is produced by Stitcher and Dubner Productions. This episode was produced by Daphne Chen. Our staff also includes Allison Craiglow, Greg Rippin, Zach Lipinski, Mary DeDuke,

Matt Hickey, and Corinne Wallace. Our intern is Emma Terrell. We had help this week from James Foster. Our theme song is Mr. Fortune by The Hitchhikers. All the other music was composed by Luis Guerra. You can get Freakonomics Radio on any podcast app, but if you want the entire back catalog, use the Stitcher app or go to Freakonomics.com, where we also publish transcripts and show notes. As always, thanks for listening.

It turned out that one of the stores that opened up around the corner from my home put new HVAC units on the roof. Did they know that you live nearby? How dare they? They found that out pretty quickly.