Louisa, Ky., is a small town of about 2,600 on the border of West Virginia with a single pair of railroad tracks running through it. If you follow these tracks south, against the flow of the Big Sandy River, you’ll go between the public library and the Main Street Park and over Lick Creek, one of the manifold creeks that web eastern Kentucky like capillaries. Follow Lick Creek past a baseball diamond and a pawnshop and you’ll arrive behind an ordinary gray mobile home in a small lot of grass where Ingrid Jackson was living in the fall of 2023. The days were still long and the afternoon sun settled gently on nearby mountains, turning leaves a lambent red. Reedy gospel music played from inside the trailer, announcing Jackson’s presence as she opened the door. Her hair, normally figured in light brown curls, was packed into a shower cap. She smiled from the entryway. It was a smile difficult not to smile back at.Listen to this article, read by Eric Jason MartinJackson had never lived in a trailer before, or a small town. She was born in Louisville, the daughter of a man with schizophrenia who, in 1983, decapitated a 76-year-old woman. Jackson was 1 at the time. In 2010, at 27, she was in a car accident and was prescribed pain pills. Not long after that, she began using heroin. Over the next decade she went through nine rounds of addiction rehab. Each ended in relapse. Her most recent one came in 2022 after her son was sentenced to life in prison for murder; he was 21. In Louisville on Christmas Day she called a residential rehab company named Addiction Recovery Care, which has its headquarters in Louisa. So now she was here, in Appalachian coal country, in a trailer along Lick Creek, in a town a tiny fraction the size of her home city, working as a nursing assistant in a nearby nursing home, sharing a trailer with Latasha Kidd, a local woman 12 years her junior with a mountain accent, a fade and blood-orange bangs. “This is culture shock,” Jackson said. “I’m a city girl, and there’s not a lot of us around, and I’m like: Mama!”Louisa, a town of about 2,600 on the border of West Virginia, suffered with the contraction of the coal industry, but ARC, in addition to its treatment centers, has opened a cafe, a bakery, a small gallery, an old theater that the company renovated and other businesses where clients in its recovery programs work.Stacy Kranitz for The New York TimesJackson and Kidd were about as different as you could make them. Jackson was Black, Kidd white; Jackson outgoing, Kidd reserved; Jackson neat, Kidd messy; Jackson devout, Kidd agnostic; Jackson straight, Kidd queer. Still, they became fast friends in rehab and now, five months out, inhabited a somewhat fragile existence together, in the period of addiction recovery that many people in long-term recovery say is the most difficult: the space between leaving rehab and getting back on your feet. More than a million people in the United States are arrested every year on drug-related charges, and for them, finding a steady job, consistent housing and reliable transportation can be even more difficult than the tremors, hallucinations and nausea of detox. Studies have shown that relapse rates for people in recovery may be as high as 85 percent within the first year. Another woman with whom Kidd and Jackson went through recovery, who was supposed to live with them, relapsed and overdosed the day before moving in.Jackson often worried that something similar might happen to Kidd, who had struggled with addiction so long that, until recently, she didn’t know how to pay her bills. At 29, Kidd hadn’t yet held a full-time job. “So I have to push her sometimes,” Jackson said. “ ’Cause when I want to go in my own direction, I don’t want Tasha to be left upside-down.”We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Public employees in West Virginia who took the drugs lost weight and were healthier, and some are despondent that the state is canceling a program to help pay for them.Joanna Bailey, a family physician and obesity specialist, doesn’t want to tell her patients that they can’t take Wegovy, but she has gotten used to it.Around a quarter of the people she sees in her small clinic in Wyoming County would benefit from the weight-loss medications known as GLP-1s, which also include Ozempic, Zepbound and Mounjaro, she says. The drugs have helped some of them lose 15 to 20 percent of their weight. But most people in the area she serves don’t have insurance that covers the cost, and virtually no one can afford sticker prices of $1,000 to $1,400 a month.“Even my richest patients can’t afford it,” Dr. Bailey said. She then mentioned something that many doctors in West Virginia — among the poorest states in the country, with the highest prevalence of obesity, at 41 percent — say: “We’ve separated between the haves and the have-nots.”Such disparities sharpened in March when West Virginia’s Public Employees Insurance Agency, which pays most of the cost of prescription drugs for more than 75,000 teachers, municipal workers and other public employees and their families, canceled a pilot program to cover weight-loss drugs.Some private insurers help pay for medications to treat obesity, but most Medicaid programs do so only to manage diabetes, and Medicare covers Wegovy and Zepbound only when they are prescribed for heart problems.Over the past year, states have been trying, amid rising demand, to determine how far to extend coverage for public employees. Connecticut is on track to spend more than $35 million this year through a limited weight-loss coverage initiative. In January, North Carolina announced that it would stop paying for weight-loss medications after forking out $100 million for them in 2023 — 10 percent of its spending on prescription drugs.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

When Joshua Knobe was younger, he knew an indie rock musician who sang sorrowful, “heart-rending things that made people feel terrible,” he recalled recently. At one point he came across a YouTube video, set to her music, that had a suicidal motif. “That was the theme of her music,” he said, adding, “So I had this sense of puzzlement by it, because I also felt like it had this tremendous value.”Listen to This ArticleFor more audio journalism and storytelling,

In a recent experiment, researchers used large language models to translate brain activity into words.Scientists recorded M.R.I. data from three participants as they listened to 16 hours of narrative stories to train the model to map between brain activity and semantic features that captured the meanings of certain phrases and the associated brain response.Think of the words whirling around in your head: that tasteless joke you wisely kept to yourself at dinner; your unvoiced impression of your best friend’s new partner. Now imagine that someone could listen in.On Monday, scientists from the University of Texas, Austin, made another step in that direction. In a study published in the journal Nature Neuroscience, the researchers described an A.I. that could translate the private thoughts of human subjects by analyzing fMRI scans, which measure the flow of blood to different regions in the brain.Already, researchers have developed language-decoding methods to pick up the attempted speech of people who have lost the ability to speak, and to allow paralyzed people to write while just thinking of writing. But the new language decoder is one of the first to not rely on implants. In the study, it was able to turn a person’s imagined speech into actual speech and, when subjects were shown silent films, it could generate relatively accurate descriptions of what was happening onscreen.“This isn’t just a language stimulus,” said Alexander Huth, a neuroscientist at the university who helped lead the research. “We’re getting at meaning, something about the idea of what’s happening. And the fact that that’s possible is very exciting.”The study centered on three participants, who came to Dr. Huth’s lab for 16 hours over several days to listen to “The Moth” and other narrative podcasts. As they listened, an fMRI scanner recorded the blood oxygenation levels in parts of their brains. The researchers then used a large language model to match patterns in the brain activity to the words and phrases that the participants had heard.Large language models like OpenAI’s GPT-4 and Google’s Bard are trained on vast amounts of writing to predict the next word in a sentence or phrase. In the process, the models create maps indicating how words relate to one another. A few years ago, Dr. Huth noticed that particular pieces of these maps — so-called context embeddings, which capture the semantic features, or meanings, of phrases — could be used to predict how the brain lights up in response to language.In a basic sense, said Shinji Nishimoto, a neuroscientist at Osaka University who was not involved in the research, “brain activity is a kind of encrypted signal, and language models provide ways to decipher it.”In their study, Dr. Huth and his colleagues effectively reversed the process, using another A.I. to translate the participant’s fMRI images into words and phrases. The researchers tested the decoder by having the participants listen to new recordings, then seeing how closely the translation matched the actual transcript.Almost every word was out of place in the decoded script, but the meaning of the passage was regularly preserved. Essentially, the decoders were paraphrasing.Original transcript: “I got up from the air mattress and pressed my face against the glass of the bedroom window expecting to see eyes staring back at me but instead only finding darkness.”Decoded from brain activity: “I just continued to walk up to the window and open the glass I stood on my toes and peered out I didn’t see anything and looked up again I saw nothing.”While under the fMRI scan, the participants were also asked to silently imagine telling a story; afterward, they repeated the story aloud, for reference. Here, too, the decoding model captured the gist of the unspoken version.Participant’s version: “Look for a message from my wife saying that she had changed her mind and that she was coming back.”Decoded version: “To see her for some reason I thought she would come to me and say she misses me.”Finally the subjects watched a brief, silent animated movie, again while undergoing an fMRI scan. By analyzing their brain activity, the language model could decode a rough synopsis of what they were viewing — maybe their internal description of what they were viewing.A decoded segment from brain recordings collected while a user watched a clip from the movie Sintel without sound. The decoder captured the gist of the scene.Jerry Tang and Alexander Huth, Blender FoundationThe result suggests that the A.I. decoder was capturing not just words but also meaning. “Language perception is an externally driven process, while imagination is an active internal process,” Dr. Nishimoto said. “And the authors showed that the brain uses common representations across these processes.”Greta Tuckute, a neuroscientist at the Massachusetts Institute of Technology who was not involved in the research, said that was “the high-level question.”“Can we decode meaning from the brain?” she continued. “In some ways they show that, yes, we can.”This language-decoding method had limitations, Dr. Huth and his colleagues noted. For one, fMRI scanners are bulky and expensive. Moreover, training the model is a long, tedious process, and to be effective it must be done on individuals. When the researchers tried to use a decoder trained on one person to read the brain activity of another, it failed, suggesting that every brain has unique ways of representing meaning.Participants were also able to shield their internal monologues, throwing off the decoder by thinking of other things. A.I. might be able to read our minds, but for now it will have to read them one at a time, and with our permission.

Some researchers claim that chatbots have developed theory of mind. But is that just our own theory of mind gone wild?Mind reading is common among us humans. Not in the ways that psychics claim to do it, by gaining access to the warm streams of consciousness that fill every individual’s experience, or in the ways that mentalists claim to do it, by pulling a thought out of your head at will. Everyday mind reading is more subtle: We take in people’s faces and movements, listen to their words and then decide or intuit what might be going on in their heads.Among psychologists, such intuitive psychology — the ability to attribute to other people mental states different from our own — is called theory of mind, and its absence or impairment has been linked to autism, schizophrenia and other developmental disorders. Theory of mind helps us communicate with and understand one another; it allows us to enjoy literature and movies, play games and make sense of our social surroundings. In many ways, the capacity is an essential part of being human.What if a machine could read minds, too?Recently, Michal Kosinski, a psychologist at the Stanford Graduate School of Business, made just that argument: that large language models like OpenAI’s ChatGPT and GPT-4 — next-word prediction machines trained on vast amounts of text from the internet — have developed theory of mind. His studies have not been peer reviewed, but they prompted scrutiny and conversation among cognitive scientists, who have been trying to take the often asked question these days — Can ChatGPT do this? — and move it into the realm of more robust scientific inquiry. What capacities do these models have, and how might they change our understanding of our own minds?“Psychologists wouldn’t accept any claim about the capacities of young children just based on anecdotes about your interactions with them, which is what seems to be happening with ChatGPT,” said Alison Gopnik, a psychologist at the University of California, Berkeley and one of the first researchers to look into theory of mind in the 1980s. “You have to do quite careful and rigorous tests.”Dr. Kosinski’s previous research showed that neural networks trained to analyze facial features like nose shape, head angle and emotional expression could predict people’s political views and sexual orientation with a startling degree of accuracy (about 72 percent in the first case and about 80 percent in the second case). His recent work on large language models uses classic theory of mind tests that measure the ability of children to attribute false beliefs to other people.A famous example is the Sally-Anne test, in which a girl, Anne, moves a marble from a basket to a box when another girl, Sally, isn’t looking. To know where Sally will look for the marble, researchers claimed, a viewer would have to exercise theory of mind, reasoning about Sally’s perceptual evidence and belief formation: Sally didn’t see Anne move the marble to the box, so she still believes it is where she last left it, in the basket.Dr. Kosinski presented 10 large language models with 40 unique variations of these theory of mind tests — descriptions of situations like the Sally-Anne test, in which a person (Sally) forms a false belief. Then he asked the models questions about those situations, prodding them to see whether they would attribute false beliefs to the characters involved and accurately predict their behavior. He found that GPT-3.5, released in November 2022, did so 90 percent of the time, and GPT-4, released in March 2023, did so 95 percent of the time.The conclusion? Machines have theory of mind.Michal Kosinski, a psychologist at the Stanford Graduate School of Business, has argued that large language models have developed theory of mind. Many scholars disagree.Christie Hemm Klok for The New York TimesBut soon after these results were released, Tomer Ullman, a psychologist at Harvard University, responded with a set of his own experiments, showing that small adjustments in the prompts could completely change the answers generated by even the most sophisticated large language models. If a container was described as transparent, the machines would fail to infer that someone could see into it. The machines had difficulty taking into account the testimony of people in these situations, and sometimes couldn’t distinguish between an object being inside a container and being on top of it.Maarten Sap, a computer scientist at Carnegie Mellon University, fed more than 1,000 theory of mind tests into large language models and found that the most advanced transformers, like ChatGPT and GPT-4, passed only about 70 percent of the time. (In other words, they were 70 percent successful at attributing false beliefs to the people described in the test situations.) The discrepancy between his data and Dr. Kosinski’s could come down to differences in the testing, but Dr. Sap said that even passing 95 percent of the time would not be evidence of real theory of mind. Machines usually fail in a patterned way, unable to engage in abstract reasoning and often making “spurious correlations,” he said.Dr. Ullman noted that machine learning researchers have struggled over the past couple of decades to capture the flexibility of human knowledge in computer models. This difficulty has been a “shadow finding,” he said, hanging behind every exciting innovation. Researchers have shown that language models will often give wrong or irrelevant answers when primed with unnecessary information before a question is posed; some chatbots were so thrown off by hypothetical discussions about talking birds that they eventually claimed that birds could speak. Because their reasoning is sensitive to small changes in their inputs, scientists have called the knowledge of these machines “brittle.”Dr. Gopnik compared the theory of mind of large language models to her own understanding of general relativity. “I have read enough to know what the words are,” she said. “But if you asked me to make a new prediction or to say what Einstein’s theory tells us about a new phenomenon, I’d be stumped because I don’t really have the theory in my head.” By contrast, she said, human theory of mind is linked with other common-sense reasoning mechanisms; it stands strong in the face of scrutiny.In general, Dr. Kosinski’s work and the responses to it fit into the debate about whether the capacities of these machines can be compared to the capacities of humans — a debate that divides researchers who work on natural language processing. Are these machines stochastic parrots, or alien intelligences, or fraudulent tricksters? A 2022 survey of the field found that, of the 480 researchers who responded, 51 percent believed that large language models could eventually “understand natural language in some nontrivial sense,” and 49 percent believed that they could not.Dr. Ullman doesn’t discount the possibility of machine understanding or machine theory of mind, but he is wary of attributing human capacities to nonhuman things. He noted a famous 1944 study by Fritz Heider and Marianne Simmel, in which participants were shown an animated movie of two triangles and a circle interacting. When the subjects were asked to write down what transpired in the movie, nearly all described the shapes as people.“Lovers in the two-dimensional world, no doubt; little triangle number-two and sweet circle,” one participant wrote. “Triangle-one (hereafter known as the villain) spies the young love. Ah!”It’s natural and often socially required to explain human behavior by talking about beliefs, desires, intentions and thoughts. This tendency is central to who we are — so central that we sometimes try to read the minds of things that don’t have minds, at least not minds like our own.

Walk down two flights of stairs, accessed through the back entrance of the James Hunt Funeral Home in Asbury Park, N.J., and you reach a white-walled, linoleum-floored, fluorescently-lit room, a liminal space that provides the beginning of an answer to one of the oldest and most confounding questions of the human experience: What happens to us when we die?On a recent Tuesday evening, Shawn’te Harvell walked down the steps and into the room, where two bodies, covered in white cloth, lay on gurneys. Mr. Harvell was wearing crisp gray scrubs and two-tone leather shoes. This was a departure from his usual attire, noted Vivian Velazquez, the funeral home manager. “Usually he’s here in his three-piece suit, his $500 shoes, and he doesn’t even wear that,” she said, pointing to the thin plastic apron that Mr. Harvell had tied around his waist.Mr. Harvell smiled and shook his head. His job, by most metrics, is a messy one. He was in the room to embalm the bodies — to drain the blood vessels and cavities filled with fluid, refill them with preservatives, scrub the skin, suture any cuts, clean the teeth, sew the mouths closed. He was there to massage the illusion of life back into cold, dead cells. But Mr. Harvell has been studying embalming and practicing as an embalmer for nearly a quarter of a century, beginning when he was 16. So, no apron necessary.Shawn’te Harvell is a professor of mortuary science, the manager of the James Hunt Funeral Home and a trade embalmer in New Jersey.James Estrin/The New York TimesNow in his 40s, Mr. Harvell is a professor of mortuary science at a local college, the manager of his own funeral home in Elizabeth and a trade embalmer who does nearly 50 embalmings a week; he is familiar with the often fraught area between life and death. “My ultimate goal is to give them their loved one back,” he said of the people who would view the bodies at the upcoming funerals. “I’ve had families come up to me and tell me, ‘Wow, they look so nice I couldn’t even cry.’”But the world he belongs to, the world of embalming, is increasingly losing its sway over the American way of death.Data gathered by the National Funeral Directors Association shows that nearly 60 percent of Americans were cremated in 2021, an increase from around 25 percent in 1999. More than 60 percent of people surveyed were interested in having so-called green burials, which are cheaper than traditional funerals and limit the chemicals allowed into the body for preservation. Embalmers are becoming more difficult to find; most funeral homes rely on contractors like Mr. Harvell, who may be the sole embalmers for a dozen funeral-home clients.According to people in the industry, things have been trending away from embalming for decades. “Absolutely there’s a shift going on,” said Tim Collison, the chief operating officer of The Dodge Company, the largest embalming fluid manufacturer in the country. “There’s less demand — it’s not an expanding market.” Dr. Basil Eldadah, a physician with the National Institute on Aging, said, “We’re just in this place in our society where we’re questioning the way that things have always been done.”The end beginsAll human life is funneled through the narrow channel of death. The heart stops beating, neurons stop firing, muscles tense and begin to decay, cells decompose. From then on, the possibilities only expand.You can be embalmed with formaldehyde and placed in a coffin underground; cremated in a furnace; left out in the open air; liquefied in an alkaline solution; composted under a pile of mulch; frozen in a cryogenic container; mummified; planted at the roots of a sapling. Ed Bixby, who owns 13 cemeteries around the country, said a new technique of treating dead bodies comes into fashion every year or so. Would you rather not have your ashes compressed into a diamond? Then how about freeze-drying your body and vibrating it into dust?But, Mr. Bixby added, nothing has managed to outlive cremation and embalming and burial: “Everyone just goes with the norm because that’s what’s normal.”The James Hunt Funeral Home. “My ultimate goal is to give them their loved one back,” Mr. Harvell said of mourners.James Estrin/The New York TimesMethods of body preservation go back thousands of years, to the 7,000-year-old Chinchorro mummies found in the Atacama Desert in Chile. But the most famous examples are from ancient Egypt. Deceased pharoahs and members of wealthy families underwent a monthslong mummification process that involved removing their internal organs, drying their bodies out with natron salt and rubbing oil on their skin. Behind this ritual was the idea that a part of the person’s spirit lived in the body, and that it would be lost if the body was destroyed. The process was so effective that some mummies could be dug up by archaeologists, with the skin and facial structure more or less intact, 4,000 years later.Egyptian mummification, aimed at eternity, bears little resemblance to modern American embalming, which began during the Civil War, when bodies of soldiers had to be transported on hot, unventilated trains. The objective was temporary preservation, maintaining an illusion of life just long enough for people to say goodbye. Abraham Lincoln was embalmed and paraded around the country after his assassination in 1865, the embalming treatment continually applied as his death tour went on for weeks. As embalming gained popularity and legitimacy through the 20th century, the viewing of the body often served as the centerpiece of the funeral ritual.Methods and intent vary widely, shaped by cultural and circumstantial forces. But the belief underlying these ancient and modern practices seems to be somewhat universal — that the body contains some part of the person, some essence, some meaning.“It’s quite profound,” said Dr. Raya Kheirbek, the chief of the Division of Geriatrics and Palliative Medicine at the University of Maryland School of Medicine. “Even after death claims the body, we’re going to beautify it in some way — like, death cannot win.”‘You’ve got to die from something’Downstairs in the James Hunt Funeral Home, Mr. Harvell moved swiftly and deftly. The two bodies he was embalming were opposites: one small and bony, almost to the point of emaciation, the other large, the legs and feet swelling with edemas.Every embalmer has a signature, Mr. Harvell said, as he pulled 16-ounce bottles of embalming fluid from the shelves of a tall wooden closet in the corner of the room. A bottle of orange fluid from The Dodge Company, 20 percent formaldehyde gas, dissolved in water — “20-index” — and mixed with plasticizers to keep the body from stiffening. A bottle of blue, 36-index fluid from Bondol Labs; designed for “frozen, refrigerated and cold bodies,” it contained salts with large ions to draw fluid out of the skin and keep it in the capillaries. A bottle of violet-red 18-index fluid from the Embalmers Supply Company for color and firmness. “We all have a certain thing we do,” Mr. Harvell said, dumping the liquid into a plastic tub atop a pressurized machine to create a frothy, turquoise mixture.Embalming fluids.James Estrin/The New York TimesShawn’te Harvell, left, does nearly 50 embalmings a week. He has been studying or doing embalming for more than 25 years.James Estrin/The New York TimesFormaldehyde sits at the heart of the embalming process. The gas fixes onto tissue proteins, stiffening them and inhibiting decomposition for roughly 24 hours. It is a vast improvement over the earliest embalming techniques, which sometimes entailed soaking a body in alcohol. But exposure to formaldehyde has been linked to cancer, and the door to Mr. Harvell’s room was plastered with biological hazard signs. He seemed unconcerned. “You’ve got to die from something,” he said with a shrug.The trick is to distribute the fluid throughout the body, starting with a two-inch cut above the clavicle, through which arterial fluid is pumped into the carotid artery. The stomach is emptied, the contents replaced with high-index cavity fluid that dries and firms up the insides. The skin is scrubbed and washed, the cut sutured shut, the lips sewed together, makeup applied.But to say that this is the extent of embalming, to embalmers, is like saying to a painter that painting consists only of long and short brushstrokes, or saying to a writer that writing consists only of subjects and clauses. Mr. Harvell, looking up from his work, said, “I can teach the fundamentals of embalming, but to do it proficiently, to do it with that …” — he twisted his fist forward and back for emphasis — “you got to have it in you.”There are products that dry out tissue, preventing liquid from leaking out of the pores of bloated bodies; powders to seal particularly large cuts; fluids with hues that counter the yellowing of jaundice. Dodge’s best-selling chemical is Introfiant, a high-index arterial fluid that some embalmers call Purple Jesus. “That’s because if they had to say a prayer to get the embalming done, they would grab the Introfiant,” Mr. Collison said.But merely knowing the embalming basics and having the right tool kit is insufficient, said Krystal Osborne, an embalmer based in Las Vegas: “You’re given a picture, and you’re creating that person all over again.”The casket showroom at Mr. Harvell’s funeral home. Nearly 60 percent of Americans were cremated in 2021, an increase from around 25 percent in 1999. James Estrin/The New York TimesTo embalm or not to embalmA few years ago, Dr. Kheirbek was invited to the funeral of one of her patients. It had been a week since the man had died, and Dr. Kheirbek and her team stood over the embalmed body, which lay in an open casket in the funeral home.“For a moment, we thought we’d gone to the wrong visitation,” she later wrote in a journal article. “He looked better than he ever looked during the months we cared for him. His face was pink and smooth, his hair nicely groomed, and he sported a quiet smile. The Mr. Thompson we knew was a skeleton, with tight-drawn skin, long curly hair, and a shaggy beard.”This incongruity triggered something in Dr. Kheirbek. It almost felt wrong to her, she wrote, like a willful blinding. The man was dead; why did he look like he was alive?Jessica Mitford, in her 1963 book about the funeral industry, “The American Way of Death,” noted pointedly that many funeral homes took financial advantage of their customers by preying on “the disorientation caused by bereavement” and “the need to make an on-the-spot decision.” Today, the average embalming and funeral costs nearly $10,000. Burial plots and headstones cost even more. Much of this can ease the grieving process for people, Dr. Kheirbek said. But, she added, why pump the body with chemicals and restore it to reflect some past self?In Japan, Nepal, Korea and Taiwan, nearly every body is cremated, while in most other countries, bodies are buried without being preserved artificially. Religion often plays an important role in these practices, but it can’t explain everything. The collection of trendy alternatives to embalming, burial and cremation that spring up each year often claim to be not just another option of body disposition, but a challenge to the social norms that shape how we treat and view the dead body.Among the more prominent movements is that of the green burial. Some experts estimate that cremation in the United States releases half a million tons of carbon dioxide into the atmosphere each year. Others note that burials introduce four million tons of embalming fluid into the ground, and 1.6 million tons of concrete.Ed Bixby owns 13 cemeteries and promotes natural burials using biodegradable coffins.James Estrin/The New York TimesMr. Bixby is the president of the Green Burial Council, a nonprofit that promotes natural burials, which consist of placing bodies in biodegradable coffins to reduce environmentally harmful waste. Dr. Eldadah, who is working to open a green-burial cemetery in Maryland, said that natural burials offered a potent philosophical alternative to what the philosopher Thomas Nagel called “the expectation of nothingness.”“It’s not this fatalistic understanding of death as unavoidable, but it is a part of the cycle of life,” Dr. Eldadah said. “We need death in order to live happy lives, making space in order for more life to emerge.”Dr. Kheirbek, who is friends with Dr. Eldadah, added: “And that’s the utmost love, I think. To just be able to let go.”Mr. Collison’s company has developed a formaldehyde-free embalming fluid as a way to cater to the growing green burial demand, but he noted that of the nearly 50 billion pounds of formaldehyde that are produced every year, only a few million pounds end up in embalmed bodies. “When you look at the funeral service from a worldview, it doesn’t make a lot of sense,” he said of embalming. “But I think there’s a basic human need to say goodbye.”A chapel built by Mr. Bixby; it is a replica of his family chapel, which was constructed in 1910.James Estrin/The New York TimesLife and everything afterAs Mr. Harvell embalmed the two bodies, massaging stiffness out of the joints and pushing the arterial fluid through the blood vessels, Ms. Velazquez and Xenia Ware, the owner of the funeral home, stood nearby and chatted about clients. One family, they said, had insisted on holding a funeral service in northern New Jersey, then leading a procession an hour south on the Garden State Parkway to the burial.Mr. Harvell seemed to register what was being said, while fragmenting his attention toward his work and the Airpod Pro that was squeezed into his right ear, through which he was carrying on a conversation with a friend. “That’s fine,” he whispered, and it was hard to tell whether he was speaking to the living or the dead.The air in the basement room was slowly filling with formaldehyde, which carried with it a cloying odor. The fluid had been emptied out of the machine, the blood drained into buckets hanging off the end of the gurneys; Mr. Harvell washed the bodies again, massaging them as he went. He put dots of oil gel on their faces to moisturize the skin, then recalled aloud how a man had once called him to arrange his own funeral.“He said, ‘I’ll be gone in about two weeks,’” Mr. Harvell said. “And I said, ‘Nah, you’ll be OK.’” The man seemed strong to Mr. Harvell; he knew him from the community, and it seemed preposterous that he could die on such a tidy schedule. Two weeks later, though, he was gone. “And that really did something to me,” Mr. Harvell said. “A person was just here, and laughing and joking, and, next thing you know, they’re not around any more.”Mr. Harvell mentioned that his own brother had died, suddenly, in 2013. Then his grandmother in 2016. Then another brother in 2018. He embalmed them all. “A lot of times, I think this is what happens to us,” he said. “The people who go on and pass away, they’ve accepted it. It’s who they leave behind, we’re not letting go.”Ms. Velazquez, in the doorway, recalled how difficult it had been when her husband died unexpectedly. People tried to talk to her, to console her. “To me, it’s just, like, just let me be,” she said. “Don’t try for nothing. It’ll go away by itself.”The room was quiet. Formaldehyde can make your eyes water and your nose run, and I was sitting in the room, burning tears on my cheeks as Mr. Harvell continued to work on the body in front of him, which had belonged to a small, slight woman. I rubbed my eyes, and Ms. Velazquez looked at me, smiling, her eyes red, too.“Aw, he’s crying for you!” she said to the body, addressing it by the woman’s name.Mr. Harvell looked up, his concentration broken for a second, and laughed. “He’s crying and he didn’t even know the lady!” he said. “See?” And he pointed to his face. “My eyes are dry.”

Nearly two-thirds of doctors are experiencing at least one symptom of burnout, a huge increase from before the pandemic. But the situation is not irreparable, researchers say.Ten years of data from a nationwide survey of physicians confirm another trend that’s worsened through the pandemic: Burnout rates among doctors in the United States, which were already high a decade ago, have risen to alarming levels.Results released this month and published in Mayo Clinic Proceedings, a peer-reviewed journal, show that 63 percent of physicians surveyed reported at least one symptom of burnout at the end of 2021 and the beginning of 2022, an increase from 44 percent in 2017 and 46 percent in 2011. Only 30 percent felt satisfied with their work-life balance, compared with 43 percent five years earlier.“This is the biggest increase of emotional exhaustion that I’ve ever seen, anywhere in the literature,” said Bryan Sexton, the director of Duke University’s Center for Healthcare Safety and Quality, who was not involved in the survey efforts.The most recent numbers also compare starkly with data from 2020, when the survey was run during the early stages of the pandemic. Then, 38 percent of doctors surveyed reported one or more symptoms of burnout while 46 percent were satisfied with their work-life balance.“It’s just so stark how dramatically the scores have increased over the last 12 months,” said Dr. Tait Shanafelt, an oncologist at Stanford University who has led the research efforts.Burnout among physicians has been linked to higher rates of alcohol abuse and suicidal ideation, as well as increased medical errors and worse patient outcomes. In May, the U.S. Surgeon General, Dr. Vivek Murthy, issued an advisory.“Covid-19 has been a uniquely traumatic experience for the health work force and for their families,” he said, adding, “if we fail to act, we will place our nation’s health at risk.”Dr. Shanafelt noted that most of the studies on burnout among physicians and health care workers at this stage of the pandemic have been focused on certain specialties and geographic hot spots, not on the profession as a whole. With the new data set, he said, “We have, for the first time, real context.”While the idea of burnout has become ubiquitous, the condition has a definition in medical literature. The Maslach Burnout Inventory, first published in 1981, measures burnout on three dimensions: emotional exhaustion, depersonalization from work and sense of personal accomplishment.When the metric was first proposed, a widely held belief was that burnout could be blamed on the dispositions of individual physicians — “that these are just weaklings,” explained Dr. Colin West, a physician at the Mayo Clinic who helped conceive of the survey efforts. Over time, though, the problem persisted and that belief became outdated.“This couldn’t just be pawned off as a handful of people who couldn’t handle the career,” Dr. West said.In 2019, the National Academy of Medicine released a 312-page report on physician burnout, carefully laying out the current understanding of the issue and steps that people in the medical profession could take to address it. Dr. Shanafelt, who helped write the report, said that evidence suggested that many doctors’ dissatisfaction with their work could be caused by an incongruence between what they cared about and what they were incentivized to do by the health care system.“We cared about quality of patients’ experience, building relationships with them, and then there were all these things we got paid for,” Dr. Shanafelt said. A doctor may stop looking forward to patient visits if each one is accompanied by a large amount of paperwork; they may feel as if their time is being wasted by an inefficient process.“Even something that was once a good thing can become tarnished,” he added.The survey showed that some physicians were at higher risk of burnout, including those practicing emergency medicine, family medicine and pediatrics, as well as women physicians in general.Erin Schaff/The New York TimesThe researchers noted that the most recent survey’s broad scope has limitations. About 2,500 physicians participated by responding to a mass email, a fraction of the estimated one million practicing physicians in the United States. And the factors that might lead someone to complete a survey on burnout — such as the need for an outlet to express frustration or the lack of time to complete one — could have had complicating effects.Doctors also exist within an ecosystem of other health workers. Dr. Sexton published a study of more than 70 hospitals this month that showed burnout is often a local phenomenon. “A lot of a person’s exhaustion score is connected to who they work with,” he said. “There’s a social contagion in burnout. If your colleagues are fried and you’re not, give it six months and you’ll look just like them.”Doctors were unevenly affected by the early stages of the pandemic. While emergency physicians and family physicians worked around the clock, constantly exposed to Covid-19, many physicians in other specialties were able to reach their patients through telehealth appointments and spend more time with their families. Combined with a possible optimism that the worst of the pandemic was over, the rise of remote work might explain why emotional exhaustion rates actually fell among surveyed physicians in mid-2020 to the lowest point since the survey began in 2011.But two and a half years into the pandemic, the most recent survey pointed to an overall decline in mental health.The survey also suggested that some physicians were at higher risk of burnout, including those practicing emergency medicine, family medicine and pediatrics, as well as women physicians in general. Dr. Shanafelt said this might be because of the shortage of mental health services. “They’ve got 10 minutes to take care of their patients. There’s no psychiatrist or therapist to refer them to because our health care system is overwhelmed,” he said.The increase in burnout is most likely a mix of new problems and exacerbated old ones, Dr. Shanafelt said. For instance, the high number of messages doctors received about patients’ electronic health records was closely linked to increased burnout before the pandemic. After the pandemic, the number of messages from patients coming into physicians’ In Baskets, a health care closed messaging system, increased by 157 percent.And physicians pointed to the politicization of science, labor shortages and the vilification of health care workers as significant issues. In one survey published in 2021, 23 percent of physicians reported being bullied, threatened or harassed by their patients at work in the past year.Dr. Sexton added: “On a hopeful note, we know that there are simple interventions that can have as much a positive effect on well-being as the pandemic had a negative effect. So, yes, things are worse during the pandemic, but they’re not so bad that we don’t know how to fix it.”Dr. West, who has done research on how to combat burnout among health care workers, said that “all the solutions run through a common pathway”: They connect people with their most meaningful activities.“What that means is it’s less important what the specific tactic is,” he said, “and more important to make sure that, whatever the solution is, it’s aligned with our basic, fundamental goals.”But Dr. West emphasized the need for data to know the prevalence of burnout and how to combat it.“This really provides a 30,000-foot view pulse check,” he said of the survey. “So that we’re not just guided by our feelings and our intuition.”

As combat sports grow in popularity, ringside physicians grapple with the precarious ethics of their role.CHATTANOOGA, Tenn. — Late one Saturday evening in June, two men in their 20s stood across from each other, shirtless and swaying, in a mixed martial arts cage in Exhibit Hall B of the Chattanooga Convention Center. The mat was sticky, a dark canvas of blood and foot sweat. Something in the combatants’ eyes made them look both terrifying and terrified, wolflike and rabbitlike at once.The bout was one of 12 that evening in the B2 Fighting Series 166, an amateur event, and Dr. Danielle Fabry, a primary care physician with a private practice in Nashville, had been hired to make sure no one got seriously hurt. Stationed by the cage door, she had the best seat in the house.Combat sports run on the excitement of an unstable equilibrium. In a perfectly matched fight, combatants trade blows until the final bell, bringing their bodies as close as possible to their limits. One mistake, though, and it ends violently. This combination of uncertainty and danger has helped transform mixed martial arts over two decades from a siloed obsession, illegal in a number of U.S. states, to a multibillion-dollar industry.But even here there are limits to the harm allowed. Referees, often former fighters or trainers themselves, can stop a fight if they think a fighter is too injured to defend him- or herself. So can ringside physicians, who determine whether fighters are fit to step into the ring and to stay there. In combat sports, physicians have had to reckon with the precarious ethics of their role.“I’m clearing someone to fight today, 20 years from now he walks into my office and has C.T.E., he has Parkinson’s,” said Dr. Nitin Sethi, a neurologist at Weill Cornell Medicine and board member of the Association of Ringside Physicians, or A.R.P., which formed in 1997. “Every doctor who works ringside should feel conflicted.”Dr. Fabry sits ringside, watching a fight and trying to make sure no one gets seriously injured. “You can never tell how it’ll go,” she said.Bee Trofort for The New York TimesIn 2019, Dr. Sethi stopped a fight at Madison Square Garden between two U.F.C. fighters, Nate Diaz and Jorge Masvidal. With the fourth round about to start, a deep cut above Mr. Diaz’s eye opened up; he seemed heavily concussed, and the skin on his forehead was drooping over his eye. When Dr. Sethi intervened, the crowd booed and both fighters protested; afterward, his office phones rang off the hook with abusive messages.“But how can you let a fighter who is getting injured on your watch go on?” said Dr. Sethi, who has worked ringside for a decade. He quickly noted the paradox of this statement; every moment he sits beside the ring is a moment he lets fighters get injured. “It’s impossible to make this sport safe,” he said.Dr. Fabry, who started her private practice in 2021, has been doing ringside work for a little over a year. When the opening bell rang in Chattanooga, she leaned forward in her seat and watched the two fighters move toward each other. It wasn’t Madison Square Garden, but the medical stakes — for her and for the combatants — were just as high.“You can never tell how it’ll go,” she said. In her previous event, a fighter had taken three minutes to revive after being knocked out cold by an uppercut.“That scares me,” Dr. Fabry said. “That’s where you start to say, ‘OK, this is serious.’” She added: “At the same time, they’re all adults. They know what they’re getting into.”The Check-InDr. Fabry performing pre-fight physicals in a makeshift locker room at the Chattanooga Convention Center.Bee Trofort for The New York TimesDr. Fabry drove down from Nashville on Friday, the day before the fight, with her boyfriend and a friend. By 4 p.m. on Saturday, she was in a makeshift locker room, working through pre-fight physicals for more than a dozen jittery men.“You see the adrenaline from the second they walk into the room,” Dr. Fabry said as she waited for one man’s blood pressure reading and studied the quivering pupils of another.“Push me away,” she instructed the second man — a test of his mobility and ability to follow basic directions. “Pull me toward you.” Then: “Can you feel when I rub down your arm?” He obeyed as the other man looked on. “Hopefully you’re not fighting each other,” she joked. They were not.Growing up in Cincinnati, Dr. Fabry had attended a couple of combat events, but her interest blossomed in medical school, when she picked up boxing to relieve stress. “I feel like I always look at it as a doctor,” she said. “I’m like, ‘Oh, that’s going to be a problem.’ But I love boxing, and I love M.M.A. It’s something that I want to be a part of.”In 2021, shortly after moving to Nashville, she heard that fight promoters were looking for physicians to sit ringside in Kentucky and Tennessee. She quickly had six job offers. A gig typically paid a couple hundred dollars, plus travel and lodging — a free weekend trip, a free fight. She decided to try it.Pre-fight physicals include eye checks, but they are not always comprehensive.Bee Trofort for The New York TimesProfessional combat sports are overseen by state agencies, and the standards for medical screenings vary. New York requires fighters to undergo a neurological exam, electrocardiogram, dilated eye exam and an M.R.I. before each fight. Most other states just ask for blood work, to check for blood-borne diseases, and a physical. The ringside physician interprets the results and decides who can or cannot fight.“The commission doesn’t give you anything,” Dr. Fabry said of Tennessee’s medical guidelines for amateur fights, which are overseen by the International Sport Karate Association, or I.S.K.A. “They just give you a short thing” — a vague, quarter-page checklist of body parts and organ systems. Eyes? Check. Abdomen? Check. Neurological? Check.To fill in her knowledge, Dr. Fabry said, she spent a few days looking over sports-physical checklists online: “I wanted to know, ‘What else should I be looking for?’” After a couple of fights, she had the hang of it. “It’s a lot like the physicals I do as a primary care physician, just a lot faster,” she said.In Chattanooga, a blood pressure monitor on one of the fighter’s arms beeped ready: 210 over 185. Dr. Fabry shook her head. The number was way too high; if correct, it could indicate an underlying heart condition. But the man was nervous and chattering, and, like most fighters, he had probably dehydrated himself to make his weight class; most have elevated blood pressure before a fight. Dr. Fabry was also thinking about the crowd, the promotion and the man’s opponent, who had come from Knoxville for the event.“You feel bad, because it’s your call, and you’re, like, ‘I just messed the whole card up for this guy,’” she said.To the fighter she said: “That’s too high. Tough weight cut?” He shrugged. “OK, stop talking and relax,” she said. She took his blood pressure again: 161 over 86. “Much better,” she said, and cleared him to fight.‘Why We Do What We Do’An amateur U.F.C. fighter has his eyes scanned by Dr. Fabry, who has boxed recreationally.Bee Trofort for The New York TimesAfter check-in, the fighters gathered awkwardly in the locker room as officials laid the ground rules: No kneeing a downed opponent. No elbows to the face. No eye pokes, crotch shots, glove-grabbing. “The number one thing for us is fighter safety,” said Brandon Higdon, a B2 promoter.Bobby Wombacher, the night’s referee, added: “It’s all about fighter safety.” Todd Murray, who was overseeing the event for the I.S.K.A., chimed in: “We don’t want any of y’all getting hurt.”As the meeting ended, Mr. Higdon hinted that he might give a $100 “locker-room bonus” to fighters who could pull off special finishes — something more dramatic than a judge’s decision. Amateur fighters are otherwise unpaid. In contrast, the U.F.C. pays its top fighters for each bout, plus as much as $50,000 for a particularly spectacular knockout or submission.The regulation of combat sports is inherently contradictory: A good fight is violent and unsafe — but not too violent or unsafe. (The U.F.C. has fired officials who have allowed fights to go on too long.) From a medical standpoint, each time a fighter is hit in the head, he or she risks a brain bleed that can kill within minutes. And repeated trauma can result years later in chronic traumatic encephalopathy, or C.T.E., which can cause aggressive behavior, depression and eventually dementia.Many physicians, as well as the American Medical Association and the World Medical Association, have called for the elimination of sanctioned combat sports. “We need to spread the word that brain-bashing is not a socially acceptable spectator sport,” Dr. Stephen Hauser, a neurologist at the University of California, San Francisco, wrote in 2012 in the medical journal Annals of Neurology.For those who opt to be involved, the A.R.P. has created a standardized set of instructions and recommendations to remove some of the ambiguity of ringside medicine. The group has certified more than 100 doctors across 34 states and 11 countries since its founding.But once the bell sounds, every ringside physician is alone, charting a calculus of risk, harm and entertainment. “You cannot become a fan,” Dr. Sethi said. “You stop it too late, and the damage is already done.”While ringside physicians are required at every sanctioned combat sport event in America, some doctors and medical groups think their presence promotes unsafe behavior.Bee Trofort for The New York TimesA week earlier, Dr. Sethi and several dozen physicians had attended a virtual seminar hosted by the A.R.P. — a new course on the basics of ringside medicine. This was “Round 8,” dedicated to ethics, and it was led by Dr. Ed Amores, an emergency medicine specialist at NewYork-Presbyterian Hospital and an association board member.Dr. Amores began by showing a video of a South African boxer who had died from a subdural hematoma a couple of days earlier. The video was from the end of boxer’s tenth round, and the fight had been called; the boxer was clearly injured, punching the air above him. “This is why we do what we do,” Dr. Amores said to the attendees.At the seminar, Dr. Amores, sporting a neat goatee onscreen, seemed to be struggling with his role as a ringside arbiter. He read from an article in the Western Journal of Medicine by Dr. Suzanne Leclerc of McGill University and Christopher Herrera, a bioethicist at Montclair State University. “The mere presence of a sport physician at a boxing match lends an air of legitimacy to behavior that is medically and ethically unacceptable,” the authors had written.But, Dr. Amores countered aloud, fighters would fight with or without physician involvement. “There are people who live dangerous lives,” he said. “Do I agree with what risk they’re putting themselves in? No. But at the end of the day I just try to do whatever I can to help them.”Dr. Louis Durkin, an emergency medicine specialist at Mercy Medical Center in Massachusetts and vice president of the A.R.P., jumped in: Ringside physicians were like pulmonologists who take care of smokers, even though they disapprove of smoking. “We’re E.R. docs,” Dr. Durkin said with a laugh. “We would have nothing to do all day if it wasn’t for bad behavior.”Dr. Amores nodded, noting that the American Academy of Neurology recommends the presence of a doctor at combat events. Then he added, “Sometimes I feel very enthusiastic about making this unsafe sport safer, and sometimes I really question myself and wonder whether I really should be doing this.”Dr. Sethi spoke up: “Ed, if you’re not feeling conflicted, I think there’s something majorly wrong.”Boxers in their twenties come to Dr. Sethi all the time asking to be cleared to fight despite M.R.I.s brimming with small “white” scars that form after traumatic brain injuries. “On our watch, we probably have a bunch of athletes that are going to develop C.T.E.,” he said. “When you and I hang up our gloves, would you be comfortable going to bed and saying, ‘I did the right thing?’”After the BellTyler Britt, left, and Antonio Holt, during their fight.Bee Trofort for The New York TimesOn that Saturday night in Chattanooga, Tyler Britt entered the cage wearing a cape of animal pelts and a demon mask; it was the penultimate fight of the night, and the crowd was buzzing. He glared at his opponent, Antonio Holt, and drew a finger across his throat.Mr. Wombacher, standing in the middle of the cage, checked in with the fighters one last time. Ready? Ready. Ready? Ready. Ringside, Dr. Fabry rubbed her legs in anticipation. “This is going to be good,” she said.In front of her were the forms she had filled out during check-in; she would use the flip side and the margins to note any injuries during the fight. “There needs to be an organization to this for everyone’s safety,” she said. She had heard of the A.R.P. only recently; she felt she could figure things out pretty well on her own, she said.At one point in the bout Mr. Britt twisted underneath Mr. Holt and grabbed his right arm, pulling it back like a chicken wing — a kimura lock. “Break his arm!” yelled fans in the crowd. “Break his arm!”Mr. Holt, stuck in the lock, did not tap to concede the fight, but he did not move. The bones in his forearm looked as though they might burst through the skin. “I’m gonna break your arm,” Mr. Britt said through clenched teeth, tightening the hold.Mr. Holt reached back, trying to relieve pressure by grabbing his right hand with his left. He swiped at the air once or twice. “I think he’s trying to tap,” Dr. Fabry said aloud to herself; she was poised to rise from her seat. A broken arm could mean the end of Mr. Holt’s fighting career and thousands of dollars in medical bills.“He’s tapping! He’s tapping!” came voices from the crowd. The referee let the fight continue.Later, when the excitement had died down and the hall was emptying — after Mr. Holt managed to escape the kimura and went on to win in a technical knockout — Mr. Wombacher and Dr. Fabry stood in the locker room. There was a brief conversation about the fights, and then the doctor headed off to a bar with her companions. Mr. Wombacher lingered. He acknowledged that he could have stopped the Britt-Holt fight during the arm lock.“It was really deep,” he said, squinting. “Look — the guy kept saying ‘I’ll break your arm’ while on the ground. Well, don’t just say it. Do it.”

In an ambitious cross-cultural study, researchers found that adults around the world speak and sing to babies in similar ways.We’ve all seen it, we’ve all cringed at it, we’ve all done it ourselves: talked to a baby like it was, you know, a baby.“Ooo, hellooooo baby!” you say, your voice lilting like a rapturously accommodating Walmart employee. Baby is utterly baffled by your unintelligible warble and your shamelessly doofus grin, but “baby so cuuuuuute!”Regardless of whether it helps to know it, researchers recently determined that this sing-songy baby talk — more technically known as “parentese” — seems to be nearly universal to humans around the world. In the most wide-ranging study of its kind, more than 40 scientists helped to gather and analyze 1,615 voice recordings from 410 parents on six continents, in 18 languages from diverse communities: rural and urban, isolated and cosmopolitan, internet savvy and off the grid, from hunter gatherers in Tanzania to urban dwellers in Beijing.The results, published recently in the journal Nature Human Behavior, showed that in every one of these cultures, the way parents spoke and sang to their infants differed from the way they communicated with adults — and that those differences were profoundly similar from group to group.TanzaniaA member of the Hadza tribe sings to his infant.ChinaA mother in Beijing sings to her baby.“We tend to speak in this higher pitch, high variability, like, ‘Ohh, heeelloo, you’re a baaybee!’” said Courtney Hilton, a psychologist at Haskins Laboratories at Yale University and a principal author of the study. Cody Moser, a graduate student studying cognitive science at the University of California, Merced, and the other principal author, added: “When people tend to produce lullabies or tend to talk to their infants, they tend to do so in the same way.”The findings suggest that baby talk and baby song serve a function independent of cultural and social forces. They lend a jumping off point for future baby research and, to some degree, tackle the lack of diverse representation in psychology. To make cross-cultural claims about human behavior requires studies from many different societies. Now, there is a big one.“I’m probably the author with the most papers on this topic until now, and this is just blowing my stuff away,” said Greg Bryant, a cognitive scientist at the University of California, Los Angeles, who was not associated with the new research. “Everywhere you go in the world, where people are talking to babies, you hear these sounds.”A Toposa woman sings while holding her baby in South Sudan in 2017.Luke GlowackiAnand Siddaiah, a researcher with the project, with a young member of the Jenu Kuruba tribe in southern India.Anand SiddaiahSound is used throughout the animal kingdom to convey emotion and signal information, including incoming danger and sexual attraction. Such sounds display similarities between species: A human listener can distinguish between happy and sad noises made by animals, from chickadees and alligators to pigs and pandas. So it might not be surprising that human noises also carry a commonly recognizable emotional valence.Scientists have long argued that the sounds humans make with their babies serve a number of important developmental and evolutionary functions. As Samuel Mehr, a psychologist and director of The Music Lab at Haskins Laboratories who conceived the new study, noted, solitary human babies are “really bad at their job of staying alive.” The strange things we do with our voices when staring at a newborn not only help us survive but teach language and communication.For instance, parentese can help some infants remember words better, and it allows them to piece together sounds with mouth shapes, which gives sense to the chaos around them. Also, lullabies can soothe a crying infant, and a higher pitched voice can hold their attention better. “You can push air through your vocal tract, create these tones and rhythms, and it’s like giving the baby an analgesic,” Dr. Mehr said.But in making these arguments, scientists, mostly in Western, developed countries, have largely assumed that parents across cultures modify their voices to talk to infants. “That was a risky assumption,” said Casey Lew-Williams, a psychologist and director of the Baby Lab at Princeton University who did not contribute to the new study. Dr. Lew-Williams noted that baby talk and song “seems to provide an on-ramp for language learning” but that “there are some cultures where adults don’t talk as often to kids — and where they talk a lot to them.” Theoretical consistency, while nice, he said, runs the risk of “washing over the richness and texture of cultures.”An increasingly popular joke among academics holds that the study of psychology is actually the study of American college undergraduates. Because white, urban-residing researchers are overrepresented in psychology, the questions they ask and the people they include in their studies are often shaped by their culture.“I think people don’t realize how much that bleeds into how we understand behavior,” said Dorsa Amir, an anthropologist at the University of California, Berkeley, who collected recordings from the Shuar in Ecuador for the new study. “But there are very different ways of being human.”Manvir Singh, an anthropologist and an author on the new study, recording speech in southern Siberut, Indonesia, in 2017.Manvir SinghIn a previous study, Dr. Mehr led a search for universal characteristics of music. Of the 315 different societies he looked at, music was present in every one. A vindicating finding and a rich data set, but one that raised more questions: How similar is the music in each culture? Do people in different cultures perceive the same music differently?In the new study, the sounds of parentese were found to differ in 11 ways from adult talk and song around the world. Some of these differences might seem obvious. For instance, baby talk is higher pitched than adult talk, and baby song is smoother than adult song. But to test whether people have an innate awareness of these differences, the researchers created a game — Who’s Listening? — that was played online by more than 50,000 people speaking 199 languages from 187 countries. Participants were asked to determine whether a song or a passage of speech was being addressed to a baby or an adult.PolandA mother in a rural town outside Krakow speaks to her infant.BoliviaA Quechua man sings a song for adults.The researchers found that listeners were able to tell with about 70 percent accuracy when the sounds were aimed at babies, even when they were totally unfamiliar with the language and culture of the person making them. “The style of the music was different, but the vibe of it, for lack of a scientific term, felt the same,” said Caitlyn Placek, an anthropologist at Ball State University who helped to collect recordings from the Jenu Kuruba, a tribe in India. “The essence is there.”The new study’s acoustic analysis also listed out these worldwide characteristics of baby and adult communication in a way that brought on new questions and realizations.For instance, people tend to try out many different vowel sounds and combinations when talking to babies, “exploring the vowel space,” as Mr. Moser put it. This happens to be quite similar to the way adults sing to each other around the world. Baby talk also closely matches the melody of song — “the ‘songification’ of speech, if you like,” Dr. Hilton said.This could potentially point to a developmental source of music — maybe “listening to music is one of those things that humans are just wired up to do,” Dr. Mehr said.But the jury is still out as to how these cross-cultural similarities fit into existing theories of development. “The field going forward will have to figure out which of the things in this laundry list are important for language-learning,” Dr. Lew-Williams said. “And that’s why this kind of work is so cool — it can spread.”Dr. Mehr concurred. “Part of being a psychologist is to step back and look at just how weird and incredible we are,” he said.

Smartphones, superglue, electric cars, video chat. When does the wonder of a new technology wear off? When you get so used to its presence that you don’t think of it anymore? When something newer and better comes along? When you forget how things were before?Whatever the answer, the gene-editing technology CRISPR has not reached that point yet. Ten years after Jennifer Doudna and Emmanuelle Charpentier first introduced their discovery of CRISPR, it has remained at the center of ambitious scientific projects and complicated ethical discussions. It continues to create new avenues for exploration and reinvigorate old studies. Biochemists use it, and so do other scientists: entomologists, cardiologists, oncologists, zoologists, botanists.For these researchers, some of the wonder is still there. But the excitement of total novelty has been replaced by open possibilities and ongoing projects. Here are a few of them.BotanyThe Tomato QueenDr. Martin in her office at the John Innes Center.Elizabeth Dalziel for The New York TimesCathie Martin, a botanist at the John Innes Centre in Norwich, England, and Charles Xavier, founder of the X-Men superhero team: They both love mutants.But while Professor X has an affinity for superpowered human mutants, Dr. Martin is partial to the red and juicy type. “We always craved mutants, because that allowed us to understand functionality,” Dr. Martin said of her research, which focuses on plant genomes in the hopes of finding ways to make foods — especially tomatoes in her case — healthier, more robust and longer lasting.When CRISPR-Cas9 came along, one of Dr. Martin’s colleagues offered to make her a mutant tomato as a gift. She was somewhat skeptical, but, she told him, “I would quite like a tomato that produces no chlorogenic acid,” a substance thought to have health benefits; tomatoes without it had not been found before. Dr. Martin wanted to remove what she believed was the key gene sequence and see what happened. Soon a tomato without chlorogenic acid was in her lab.Instead of looking for mutants, it was now possible to create them. “Getting those mutants, it was so efficient, and it was so wonderful, because it gave us confirmation of all these hypotheses we had,” Dr. Martin said.Most recently, researchers at Dr. Martin’s lab used CRISPR to create a tomato plant that can accumulate vitamin D when exposed to sunlight. Just one gram of the leaves contained 60 times the recommended daily value for adults.Understand Sickle Cell DiseaseThe rare blood disorder, which can cause debilitating pain, strokes and organ failure, affects 100,000 Americans and millions of people globally, mostly in Africa.The Global Epicenter: In Nigeria, where 150,000 babies are born each year with sickle cell disease, the effects of the condition are pervasive and devastating. On the Edge of Fear: A cure for the disease, which in the United States mostly affects Black people, seems near. For some, it may come too late.Preventing Complications: A legacy of neglect toward Americans with sickle cell means that patients may not receive the treatments needed to stave off the disease’s risks. A Haunting Memory: The Times reporter Gina Kolata shares her experience reporting on the inequities in access to medical advances in the treatment of the disease.Dr. Martin explained that CRISPR could be used across a broad spectrum of food modifications. It could potentially remove allergens from nuts and create plants that use water more efficiently.“I don’t claim that what we did with vitamin D will solve any food insecurity problems,” Dr. Martin said, “but it’s just a good example. People like to have something that they can hang on to, and this is there. It’s not a promise.”Infectious DiseaseBringing Testing to Remote Parts of AfricaChristian Happi directs the African Centre of Excellence for Genomics of Infectious Diseases in Nigeria.Fikayo OyewaleChristian Happi, a biologist who directs the African Centre of Excellence for Genomics of Infectious Diseases in Nigeria, has spent his career developing methods to detect and contain the spread of infectious diseases that spread to humans from animals. Many of the existing ways to do so are costly and inaccurate.For instance, in order to perform a polymerase chain reaction, or PCR, test, you need “to go extract RNA, have a machine that’s $60,000 and hire someone who is specially trained,” Dr. Happi said. It’s both costly and logistically implausible to take this kind of testing to most remote villages.Recently, Dr. Happi and his collaborators used CRISPR-Cas13a technology (a close relative of CRISPR-Cas9) to detect diseases in the body by targeting genetic sequences associated with pathogens. They were able to sequence the SARS-CoV-2 virus within a couple of weeks of the pandemic arriving in Nigeria and develop a test that required no on-site equipment or trained technicians — just a tube for spit.“If you’re talking about the future of pandemic preparedness, that’s what you’re talking about,” Dr. Happi said. “I’d want my grandmother to use this in her village.”The CRISPR-based diagnostic test functions well in the heat, is quite easy to use and costs one-tenth of a standard PCR test. Still, Dr. Happi’s lab is continually assessing the accuracy of the technology and trying to persuade leaders in the African public health systems to embrace it.He called their proposal one that “is cheaper, faster, that doesn’t require equipment and can be pushed into the remotest corners of the continent. This would allow Africa to occupy what I call its natural space.”Hereditary IllnessSearching for a Cure for Sickle Cell DiseaseGang Bao, a biochemical engineer at Rice University, is working on a treatment for sickle cell disease using CRISPR.Rice UniversityIn the beginning there was zinc finger nuclease.That was the gene-editing tool that Gang Bao, a biochemical engineer at Rice University, first used to try to treat sickle cell disease, an inherited disorder marked by misshapen red blood cells. It took Dr. Bao’s lab more than two years of development, and then zinc finger nuclease would successfully cut the sickle cell sequence only around 10 percent of the time.Another technique took another two years and was only slightly more effective. And then, in 2013, soon after CRISPR was used to successfully edit genes in living cells, Dr. Bao’s team changed tack again.“From the beginning to having some initial results, CRISPR took us like a month,” Dr. Bao said. The method successfully cut the target sequence around 60 percent of the time. It was easier to make and more effective. “It was just amazing,” he said.The next challenge was to determine the side effects of the process. That is, how did CRISPR affect genes that weren’t being purposefully targeted? After a series of experiments in animals, Dr. Bao was convinced that the method would work for humans. In 2020 the Food and Drug Administration approved a clinical trial, led by Dr. Matthew Porteus and his lab at Stanford University, that is ongoing. And there is also hope that with CRISPR’s versatility, it might be used to treat other hereditary diseases. At the same time, other treatments that have not relied on gene editing have had success for sickle cell.Dr. Bao and his lab are still trying to determine all the secondary and tertiary effects of using CRISPR. But Dr. Bao is optimistic that a safe and effective gene-editing treatment for sickle cell will be available soon. How soon? “I think another three to five years,” he said, smiling.CardiologyLooking Into the Secrets of the HeartDr. Joseph Wu, director of the Stanford Cardiovascular Institute.Nina Riggio for The New York TimesDr. Wu pointed to a beating human heart stem cell on a screen in his lab.Nina Riggio for The New York TimesIt is hard to change someone’s heart. And that’s not just because we are often stubborn and stuck in our ways. The heart generates new cells at a much slower rate than many other organs. Treatments that are effective in other parts of the human anatomy are much more challenging with the heart.It is also hard to know what is in someone’s heart. Even when you sequence an entire genome, there are often a number of segments that remain mysterious to scientists and doctors (called variants of uncertain significance). A patient might have a heart condition, but there’s no way to tie it definitively back to their genes. “You are stuck,” said Dr. Joseph Wu, director of the Stanford Cardiovascular Institute. “So traditionally we would just wait and tell the patient we don’t know what’s going on.”But over the past couple of years, Dr. Wu has been using CRISPR to see what kind of effects the presence and absence of these befuddling sequences have on heart cells, simulated in his lab with induced pluripotent stem cells generated from the blood. By cutting out particular genes and observing the effects, Dr. Wu and his collaborators have been able to draw links between the DNA of individual patients and heart disease.It will be a long time before these diseases can be treated with CRISPR, but diagnosis is a first step. “I think this is going to have a big impact in terms of personalized medicine,” said Dr. Wu, who mentioned that he found at least three variants of uncertain significance when he got his own genome sequenced. “What do these variants mean for me?”BiotechnologyReinventing CerealKaren Massel, a biotechnologist at the University of Queensland in Australia.David Kelly for The New York TimesSorghum is used in bread, alcohol and cereal all over the world. But it hasn’t been commercially engineered to the same degree as wheat or corn, and, when processed, it often isn’t as tasty.Karen Massel, a biotechnologist at the University of Queensland in Australia, saw quite a bit of room for improvement when she first started studying the plant in 2015. And because millions of people eat sorghum worldwide, “if you make a small change you can have a huge impact,” she said.She and her colleagues have used CRISPR to try to make sorghum frost tolerant, to make it heat tolerant, to lengthen its growth period, to change its root structure — “we use gene editing across the board,” she said.Not only could this lead to more delicious and healthier cereal, but it could also make the plants more resistant to the changing climate, she said. But it is still no small task to accurately edit the genomes of crops with CRISPR.“Half the genes that we knock out, we just have no idea what they do,” Dr. Massel said. “The second we try to get in there and play God, we realize we’re a bit out of our depth.” But, using CRISPR combined with more traditional breeding techniques, Dr. Massel is optimistic, despite being a self-described pessimist. And she hopes that further advances will lead to commercializing gene-edited foods, making them more accessible and more acceptable. OncologyA New Treatment for CancersDr. Robert Stadtmauer, a hematologist-oncologist at Penn Medicine. “Even though it’s really sort of science fiction-y biochemistry and science, the reality is that the field has moved tremendously,” he said.Hannah Yoon for The New York TimesIn 2012, a 6-year-old girl was suffering from acute lymphoblastic leukemia. Chemotherapy had been unsuccessful, and the case was too advanced for a bone-marrow transplant. There didn’t seem to be any other options, and the girl’s physicians told her parents to go back home.Instead, they went to the Children’s Hospital of Philadelphia, where doctors used an experimental treatment called chimeric antigen receptor (CAR) T-cell therapy to turn the girl’s white blood cells against the cancer. Ten years later, the girl is cancer free.Since then, Dr. Carl June, a medical professor at the University of Pennsylvania who helped develop CAR T-cell therapy, and his collaborators, including Dr. Ed Stadtmauer, a hematologist-oncologist at Penn Medicine, have been working to improve it. That includes using CRISPR, which is the simplest and most accurate tool to edit T-cells outside the body. Dr. Stadtmauer, who specializes in dealing with various types of blood and lymph system cancers, said that “the last decade or so has just seen a revolution of treatment of these diseases; it’s been rewarding and exciting.”Over the past couple of years, Dr. Stadtmauer helped run a clinical trial in which T-cells that underwent significant CRISPR editing were inserted into patients with treatment-resistant cancers. The results were promising.“Patients that had very dismal prognoses are now doing much better, and some are being cured,” Dr. Stadtmauer said. He has continued to monitor the patients, and has found that the edited T-cells are still present in the blood, ready to attack tumor cells in the case of a relapse.The real benefit is that scientists now know that CRISPR-aided treatments are possible.“Even though it’s really sort of science fiction-y biochemistry and science, the reality is that the field has moved tremendously,” Dr. Stadtmauer said. He added that he was less excited by the science than how useful CRISPR had become. “Every day I see maybe 15 patients who need me,” he said. “That’s what motivates me.”