Today you’ll learn about how we are able to measure depression through speech patterns, a recent study that explores whether or not eating at a certain time of day affects weight, and how researchers used paintings to assess pollution levels during the industrial revolution.
Today you’ll learn about how we are able to measure depression through speech patterns, a recent study that explores whether or not eating at a certain time of day affects weight, and how researchers used paintings to assess pollution levels during the industrial revolution.
Speech Signals of Depression
What Time to Eat?
Monet Haze
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/speech-signals-of-depression-what-time-to-eat-monet-haze
[SFX: INTRO MUSIC/WHOOSH]
NATE: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. Time flies when you’re learnin’ super cool stuff. I’m Nate.
CALLI: And I’m Calli. If you’re dropping in for the first time, welcome to Curiosity, where we aim to blow your mind by helping you to grow your mind. If you’re a loyal listener, welcome back!
NATE: Today you’ll learn about how we are able to measure depression through speech patterns, a recent study that explores whether or not eating at a certain time of day affects weight, and how researchers used paintings to assess pollution levels during the industrial revolution!
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WHOOSH]
CALLI: Depression is something that affects a lot of people. But did you know that people are actually 93% accurate in detecting depression just from listening to other people speak?
NATE: I didn't know anything about that. What's the science behind this?
CALLI: Well, it started per usual with a bit of research that found that any changes in speech, like the speed or intensity or pitch or even how often we pause while speaking, can be a pretty accurate read when looking to detect depression. Now, to be clear, I'm not talking about, like, everyday sadness. I'm talking about clinical diagnosable depression. And our ears are capable of being up to 93% accurate in discovering that.
NATE: Wow. 93 sounds pretty impressive. How do we do that?
CALLI: I mean, yes, depression or major depressive disorder, as it's known, is one of the most common mental illnesses on earth and affects over 264 million people. So any method that can act as an early detector could save a lot of lives.
NATE: Okay. But there must be more to this than just listening, right?
CALLI: You are correct. And that is why this kind of listening needs to be led by even knowing what to look for. The team who researched this phenomenon developed a speech analysis test and used it on 118 subjects with no prior clinical diagnoses. The test began with an assessment called trail making, which measured how fast the participants minds worked during problem solving. Then they took an assessment in relation to depressive symptoms before they were recorded, speaking for 2 minutes. One minute about something positive in their lives and one about something negative.
NATE: I feel like you maybe could do something similar with different topics here on Curiosity. Like you one minute about how puppies are good for your brains. Yay! And then you do the next minute about how climate change is definitely going to murder us all.
CALLI: Don't call us out like that. Well, okay. Okay. So after they did this, each speech task was analyzed for a few specific criteria, acoustic features of the speech, how many words were said in total, and how many words were said before a pause occurred? Of the 118 subjects, 25 of them scored so high that they were referred to be considered for a clinical depression diagnosis.
NATE: Oof! Why?
CALLI: All those 25 subjects spoke more words than any of the other subjects that scored lower for depression and all had similar speech, speed, pitch and features. They also took more time completing the trail making test than others. Basically what it boils down to is each said more words than the other subjects, but they said them slower with more pauses and in a more specific cadence than the other subjects.
NATE: All right. It sounds like it's really cool, but I don't feel like it's, you know, fully fleshed out. Like this sounds a bit limited to me.
CALLI: It is. And the researchers actually acknowledge that. For starters, the speech recordings were only 2 minutes in length, which isn't a very long amount of time to analyze somebody. Also, each subject was a university student. University students, for many reasons, aren't representative of a broad portion of society. And plus, the subjects weren't clinically observed, meaning it's not even possible to know if they would have been diagnosed with clinical depression in a medical setting.
NATE: Disappointed!
CALLI: Yeah. Did you just meme on me?
NATE: Well, you know, it seemed like a good way to express my opinions of the situation.
CALLI: Yeah, that's fair. Well, as disappointed as we are, none of that takes away from the study's results. This work is valuable when it comes to finding new ways to detect depression early. If this method proves successful, then anybody can do it. Because all it takes is a little bit of learning and a whole lot of focus.
[SFX: WHOOSH]
NATE: I feel like my whole life people have been telling me that there are certain times of day not supposed to be like, Don't eat too late, you're not going to digest it properly. Don't eat after midnight, you'll turn into a gremlin. Okay, so now, though, it seems like there is some science reporting that you can eat after midnight and that it won't have any negative effects.
CALLI: All right. So you're really going to bat for nightshift workers? I love that. There's a lot of science, however, that supports the idea of timed eating. So what did this study find?
NATE: That it's the amount of meals a person eats throughout the day that is more important than the time of consumption when it comes to long term changes in body weight.
CALLI: Okay. A little bit of a skeptic here. The topic of diet is always so much more complicated than people want to make it. For example, it's common knowledge that cutting some food out of your diet is a good way to lose weight. But it's also common knowledge that part of that lines up with timing your meals out. So breakfast, lunch, dinner and so on. Are you telling me that meal timing doesn't actually matter?
NATE: That's what I'm telling you. Yeah. So the evidence relating to meal timing is surprisingly controversial. One recent randomized trial showed that restricting eating to a daily window of 8 hours on top of a caloric restriction saw the exact same levels of weight loss for people with obesity as simply cutting calories. But another study on the same eight hour time frame showed the opposite, that it led to greater weight loss. And because of this uncertainty, a study into time restricted eating began.
CALLI: As somebody who has a horrible diet, I am absolutely fascinated by this study.
NATE: Okay. So this study had 547 participants that were recruited from three U.S. health systems who were followed for an average of six and a half months. They downloaded and used a mobile app called Daily 24 to record what time they ate, how long they slept, and how big their meals were. They also answered a baseline questionnaire addressing their height, weight and co-morbidities. This survey addressed the previous ten years of their medical histories. Each participant, on average, was aged 51. 78% of them were women, and all of them had been diagnosed as obese alongside other co-morbidities like hypertension, chronic obstructive pulmonary disease, diabetes and chronic kidney disease.
CALLI: Okay, but what does that have to do with mealtimes?
NATE: So the average age between first and last meals daily was 11 and a half hours with an hour and a half between waking up and the first meal and 4 hours, between the final meal and sleep. Each participant slept around seven and a half hours a night, and none of those figures were associated with changes in body weight for most of the participants medical histories.
CALLI: All right. That's not very shocking. If you eat a consistent diet, you'll stay a consistent weight.
NATE: Exactly. So the researchers shifted gears and decided to assess the relationship between number of daily meals and weight changes over time. Each participant ate an average of three meals a day. But in this new model, the researchers found that any additional meals past the base three was associated with a greater annual increase in body weight, especially if the meals were medium or large in size.
CALLI: What does this actually say, though, about intermittent fasting?
NATE: Well, the researchers make it a point to mention that their data can't really address the impact of intermittent fasting, which has grown in popularity over the past few years as a way to lose weight, because this study focused on average eating window over time, not on specific fasting behaviors on a day-to-day basis. That said, if timing doesn't have too much to do with weight loss, then a similar study on intermittent fasting could help give us that answer.
CALLI: Okay, got it. So conventional wisdom still dictates that it's the amount of food we eat, just not the time we eat it.
NATE: Exactly. The senior author of the study, Wendy Bennett, actually said that we should still be cautious about changing our dietary schedules too dramatically or else we run the risk of altering our circadian rhythms with a lopsided diet. But she still stresses that it would be worth conducting randomized trials to figure out whether meal timing during the day can affect weight trajectories.
CALLI: Good to know. For now, I'm going to stick with my midnight snacks.
NATE: You do you.
[SFX: WHOOSH]
CALLI: Art and illustration actually mean a lot to me. I used to be an illustration student and it was recently revealed that old paintings are actually more reflective of the way the world used to look than previously believed.
NATE: Oh, see, I knew that dogs actually used to know how to play poker, and they're just hiding it now. Like, I don't know why they've stopped doing it.
CALLI: Okay. No, no. I'm sorry to burst your bubble, but I am referring to painters like J.M.W. Turner and Claude Monet, who were some of the most famous impressionist painters of their time. For those who don't know, Impressionism is a style where artists will paint with an emphasis on light and its changing qualities, often in nature, spontaneously, rather than in a studio from sketches. Most impressionist art is of landscapes in everyday life, imbued with realism, which is why some of the more surreal elements have always been a hot topic in the art world.
NATE: What kinds of surreal elements?
CALLI: Well, Claude Monet was famous for painting his work with sharp edges, defined shapes, and a constant yearn for depicting a scene as accurately as possible. You can really see this in his 1867 work Sainte-Andresse, which depicts his family having conversations at a seaside resort in front of docked boats. Everything in the image is clear, realistic, and from a distance even looks almost like a photograph. But later in his career in 1899, Monet did a series about the Houses of Parliament, which shows the Houses is drawn in hazier colors with broader brushstrokes washed out by a very heavy smog. And if you look at the difference between the paintings side by side, they are really stark.
NATE: Was that a style choice?
CALLI: It might have been, but a new study that analyzed over 100 paintings from Monet, as well as J.M.W. Turner, used a mathematical model that compared how sharp the outlines of certain objects were compared to the background, as well as how intense the haze was. By measuring the level of whiteness with whiter hues indicating intense haze. Then they compared the results to the weather records from the time which led them to hypothesize that the change in art style has less to do with personal preference and more to do with the increase in industrial air pollution.
NATE: Okay, that makes some sense. If an impressionist painter is striving for realism, especially regarding light, then you know, depicting the smog would definitely be a part of that realism. But what you're saying is that for a long time it was assumed to be a style choice.
CALLI: Okay. Not a stylistic choice so much as a practical one. See, there was a prevailing theory for many decades that both Monet and Turner's eyesight had gotten worse as they got older, which would have affected their abilities to paint clear landscapes. This theory gave each artist's work sort of a bit of a tragic lens to view the art through because it showed a sort of visual decay happening across each work. But what this study found was that that couldn't be the case. Turner still painted objects in clear focus in the foreground of his paintings until the end of his life. And Monet's vision didn't actually decline until decades after his first hazy painting. Most damningly, the researchers found an archive of old letters Monet sent to his wife that completely dispel that theory once and for all.
NATE: It sounds like an oddly specific set of letters. Did he just say, “For future record, I am not blind that there is much pollution.” It is sending letters to the future. Did he have any advice about buying stocks or anything?
CALLI: I mean, no. Sorry. Sorry. They didn't. The letters actually say directly that Monet was painting what he saw and what he saw was pollution and pollution didn't excite him artistically. A quote from him and it's a little grim. “Everything is dead. No train, no smoke or boat. Nothing to excite the verve a bit.”
NATE: Oh, sounds like he was thrilled with all that. How bad was the pollution back then?
CALLI: Well, these were in the days of the early industrial revolution. Coal burning factories popped up everywhere, blowing smoke plumes filled with sulfur dioxide endlessly into the sky. Nearly half of the sulfur dioxide emissions across the planet came from the U.K. alone, from 1800 to 1850, with London accounting for 10% of that. And even though Monet's birthplace, Paris industrialized, slower than the U.K., they still saw huge increases in sulfur dioxide in the atmosphere after 1850. This kind of air pollution can radically change how landscapes look in visual ways. So it's no surprise that Monet and Turner were able to visualize this in a realistic way.
NATE: That's a really cool intersection of art and science to be able to figure out what the world was looking like in scientific terms just by analyzing art.
CALLI: What's cool is that this is actually nothing new. Portrayals of environmental changes or even meteorology in paintings is also nothing new. For example, some meteorologists argue that Edvard Munch's famous The Scream, depicts polar stratospheric clouds and others have even. Figured out that Vincent Van Gogh's Moon rise takes place at exactly 9:08 p.m. on July 13th, 1889, in Saint Rémy de Provence, France, because of the weather conditions being depicted.
NATE: So what does this mean for us?
CALLI: What it means is art and science are closer tied together than most people believe. By analyzing art at the level this team did, you can figure out why art is the way it is, or what the world was like at a time a piece of art was made.
NATE: Like back when dogs still played poker.
CALLI: Nate No.
[SFX: WHOOSH]
NATE: Let’s recap what we learned today to wrap up.
CALLI: Quick question: from the sound of my voice, can you tell if I’m depressed? A new study has learned that the human ear is capable of detecting depression, on a clinical level, with a nearly 93% success ratio. The study has only been performed on a small sample size as of now, but the results could be promising for future development in early depression detection!
NATE: If you’ve ever been told that you shouldn’t eat after a certain time, I’m pleased to announce that science doesn’t support that idea. New research suggests that it’s not the time you eat a meal, but how many meals you eat, that can affect weight loss. So as long as you stay within a good old fashioned caloric deficit, you can eat breakfast at midnight or lunch at 8pm as long as you keep your diet consistent!
CALLI: What’s the difference between art and science? Turns out - the two are more closely related than previously believed! An analysis of centuries-old impressionist art has revealed that painters like Claude Monet weren’t aiming for the “surreal” in their later-years art - they were literally painting the disgusting smog filling their sightlines! This sort of analysis not only shows us that art IS a science, but that we can learn more about the world from how art is even created!