Some eye-opening thoughts on sleep

In the U.S., it's perfectly normal to sleep with your dog or cat, but huge cultural battles are being fought over whether it's odd, or even detrimental, to sleep with your baby. In much of the developing world, people think just the opposite, says anthropologist Carol Worthman.

By Carol Clark

Emory anthropologist Carol Worthman first began thinking about the cultures of sleep while traveling across Kenya in 1979 as a postdoctoral fellow. She was headed to the coast in an old, classic train with wooden slats that rolled down over the windows. The cheap ticket section was so packed for the overnight journey that mothers and children shared bunks in the women’s section.

“Children were crying. It was really noisy and I couldn’t get comfortable. I didn’t sleep much at all,” Worthman says.

The locals, however, took it in stride. “In the morning, everyone around me got up looking bright and beaming,” Worthman says. “I thought, ‘They don’t sleep like Westerners do.’”

Nearly two decades later, Worthman was asked by a pediatrician to sum up what anthropologists know about sleep. She thought about it and had to respond, “Not much.” While most waking moments of human activity were well-documented, their sleeping ones were largely ignored by anthropologists.

“When people go to sleep is when we can finally write up our notes,” Worthman jokes.

But the realization that her field had overlooked one-third of human life spurred her to work on the first analytic framework for comparative studies of human sleep behavior in 1998.

She pored over the literature, and interviewed field researchers about their observations of the ecology of sleep from across continents, cultures and climates in the developing world. From foragers to farmers, islanders to mountain dwellers, patterns of sleep behavior began to emerge.

“I was startled,” Worthman says. “You learn just how weird our sleeping habits are in the United States.”

For instance, many Americans consider it odd, and perhaps detrimental, to sleep with a newborn baby. And yet it’s perfectly normal to sleep with a dog or cat.

“In much of the developing world, people think just the opposite,” Worthman says. “It’s pretty much universal that babies don’t sleep alone. They either lie right next to their mothers, or nearby on a mat, or in a cradle or a sling.”

Putting a baby in a separate room to sleep would be viewed as tantamount to child abuse in many cultures, Worthman says.

For much of human history, humans have slept in family groups, with one ear cocked for danger. They were comforted by the sounds of their livestock shuffling, their babies breathing and the crackle of a smoky fire to ward off bugs and larger predators. “Sleeping like a log” is not so desirable if you could roll into the fire, or miss the sound of an approaching predator.

Worthman’s work has shown that rural, and even some urban, communities of the developing world have markedly different sleeping patterns than the typical American. “You can actually quantitatively show that culture drives human sleep behavior,” she says.

Building on her decades of research, Worthman is about to launch the first quantitative study of a pre-electric sleep culture, a major experiment set to begin soon in rural Vietnam. Click here to read more about the study.

It’s only relatively recently that electricity, larger homes, box springs, non-allergenic mattresses and climate-controlled interiors have altered our sleep environments. This rapid shift leads Worthman to wonder if modern sleep practices have set us up for chronic problems such as insomnia, sleep apnea and parental anxiety over a newborn’s sleep patterns.
Photo by Klaus Roesch

For instance, in many cultures, people tend to take more naps and have less rigid expectations for sleeping straight through the night. Some evidence indicates that in pre-gaslight Europe, it was not uncommon for people to have an early evening sleep, then wake up later in the night for a while, before returning to a deeper sleep state.

Modern-day insomniacs may actually be the more normal ones, Worthman notes. “In our culture, we have this very fixed idea that you should lie down and go out like a light,” she says. “One of the problems with insomnia is that people become very anxious about it. If they relaxed, went with the flow, and perhaps took a nap during the day, maybe it would help.”

All images, iStockphoto.com, unless otherwise noted.

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Shedding light on a pre-electric sleep culture
Grandma was right: Babies wake up taller
The science of sleep

Exploring the cognitive basis of religion and science

Neuroscience promises "startling new insights about science, about religion, and about their comparison," says Robert McCauley. Photo by Kay Hinton.

The conflict between the scientific mindset and the religious mindset is an old one. What’s new are tools of cognitive science that allow us to probe why we choose to follow paths of religion and/or science, says Robert McCauley, a philosopher of science at Emory.

McCauley’s written a new book, “Why Religion is Natural and Science is Not,” in which he explains why the modern-day version of science is more in danger of extinction than religion.

Here’s an excerpt from a Boston Globe interview with McCauley:

BOSTON GLOBE: Why do you say religion is “natural” but not science?

MCCAULEY: Religion overwhelmingly depends upon what I’m calling natural cognition, thinking that is automatic, that is not conscious for the most part. Once our attention is drawn to it, we find it fairly difficult to articulate. For example, when we talk, our talking arises pretty spontaneously and yet it’s incredibly complex. We’re conforming to all sorts of rules about our natural language, which we’re usually incapable of articulating.

Science, probably more than any other human intellectual endeavor, supersedes natural cognition. It’s conscious, usually in the form of language. It’s usually slow, it’s deliberative. Science is extremely unnatural. That’s why scientists have to take courses in all these things--and then it’s still hard. The products of scientific reflection are inevitably radically counterintuitive. They challenge common sense.

Read the whole Boston Globe interview here.

And here’s a recent column by McCauley in Psychology Today.

Related:
The price of your soul: How your brain decides whether to 'sell out'

Tobacco stats can take your breath away

Globally, tobacco kills 5 million people each year, about 8.8 percent of all deaths.
Image: iStockphoto.com

On January 11, 1964, U.S. Surgeon General Luther Terry issued an official warning that smoking cigarettes can kill you. The report “hit the nation like a bombshell,” Terry later recalled. “It was front page news and a lead story on every radio and television station in the United States and many abroad."

Nearly 50 years later, however, more than 45 million American adults still smoke, more than 8 million are living with a serious illness caused by smoking, and about 438,000 Americans die prematurely each year as a result of tobacco use, according to the CDC.

The anti-tobacco movement is just getting under way in much of the developing world. Globally, tobacco kills more than 5 million people each year, accounting for about 8.8 percent of all deaths, according to the Tobacco Atlas. If current trends continue, tobacco will kill 7 million people annually by 2020 and more than 8 million people by 2030, most of them in low- and middle-income countries. (The Tobacco Atlas is produced by the World Lung Foundation and the American Cancer Society.)



“Nicotine use is a complex addiction,” said Gregory Connolly, director of Harvard’s Center for Global Tobacco Control, during a recent health conference held at Emory. If you inject someone with nicotine, you can’t make them dependent on it the way you can with heroin or cocaine, he explains. Nicotine dependency is driven by a range of factors including ease of use, chemo-sensory cues, activation of the dopamine-reward pathway and learned behavior.

Treating individuals is helpful in the short-term, but policy measures that remove smoking from the social norm are better in the long-term, Connolly said.

“Kids do what adults do,” he said. “You really have to de-normalize the behavior and take away the social benefits.”



On January 1, Emory became a tobacco-free campus. Smoking and all other forms of tobacco use are now prohibited on all Emory University and Emory Healthcare properties. More than 580 U.S. colleges and more than 2,800 hospitals and health-care organizations have adopted similar policies.

At least on U.S. college campuses, smoking is become a harder habit to continue.

Related:
Striking up conversations about smoking

Does science need a universal symbol?

Paul Root Wolpe, director of the Emory Center for Ethics, sparked a debate with his proposal in New Scientist to develop a unifying symbol for science: A sort of bumper sticker for passionate nerds, and those who support their mission. Wolpe writes:

"A single, unified symbol would have many uses. It could be displayed to represent a position: opposition to the politicizing of science in government, support for increased research spending, or concern about global warming and species loss. It could be displayed by an astronomer or geologist or sociologist or teacher as a symbol of their allegiance to science. It could be used on car bumpers and web pages, and in public venues. ...

"Perhaps it could even accommodate a cross or star of David or some other symbol to state: 'I am a Christian (or Jew or Muslim) and support science as an enterprise.'"

You can read the full New Scientist article here.

Do you agree with Wolpe? You can send your ideas for a symbol to sciencesymbol@emory.edu, or join the discussion via a special science symbol Facebook page Wolpe set up.

Graphic: iStockphoto.com.

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Blurring the lines between life forms
Why robots should care about their looks

Trees and reality TV drive discovery in 2011

In 2011, flashes of inspiration made fundamental science at Emory seem almost easy. A hike in the woods sparked a breakthrough in number theory, while an episode of “American Idol” led to an insight about the human brain.

Actually, it takes a certain brilliance to find big ideas hiding amid trees and reality TV. To paraphrase Louis Pasteur, whether you are an athlete or a couch potato, chance favors a prepared mind.

Here’s a roundup of the hottest topics on eScienceCommons for 2011.

New theories reveal the nature of numbers: For centuries, some of the greatest names in math have tried to make sense of partition numbers, the basis for adding and counting. The eureka moment finally occurred when mathematicians were hiking through the fall foliage in north Georgia and noticed patterns in the trees and the switchback trail. Partition numbers are fractal, repeating in an infinite pattern, they suddenly realized.

Teen brains can predict pop song success: A neuroeconomist was watching “American Idol” with his two young daughters when a contestant started singing “Apologize” by One Republic. The song sounded familiar, and the scientist realized that he had used it in a study. That led to a re-analysis of brain-response data of teens listening to obscure songs. The results show that teen brain activity may help predict the popularity of music.

Dawn of agriculture took toll on health: Anthropologists confirmed that when populations around the globe started turning to agriculture around 10,000 years ago, regardless of the location or the types of crops, a similar trend occurred: The height and the health of the people declined. In modern times, the stature trend has reversed: The average human height is increasing, as food becomes increasingly commercialized and abundant. But is our health improving, in an era of obesity?

Anxious kids confuse ‘mad’ and ‘sad’: Psychologists found that children suffering from extreme social anxiety are trapped in a nightmare of misinterpreted facial expressions: They confuse angry faces with sad ones. Non-verbal communication is a critical, but often overlooked, aspect of child development. The good news is that non-verbal communication skills can be improved at any age.

Chimps, bonobos yield clues to social brain: It’s been a puzzle why our two closest living primate relatives, chimpanzees and bonobos, have widely different social traits, despite belonging to the same genus. Now, a comparative analysis of their brains shows neuroanatomical differences that may be responsible for these behaviors, from the aggression more typical of chimpanzees to the social tolerance of bonobos.

Chemists reveal the force within you: A new method for visualizing mechanical forces on the surface of a cell provides the first detailed view of those forces, as they occur in real-time. Mapping such forces may help to diagnose and treat diseases related to cellular mechanics. Cancer cells, for instance, move differently from normal cells, and it is unclear whether that difference is a cause or an effect of the disease.

Hominid skull hints at later brain evolution: An analysis of a skull from the most complete early hominid fossils ever found suggests that the large and complex human brain may have evolved more rapidly than previously realized, and at a later time than some other human characteristics. While some features of Australopithecus sediba were more human-like, most notably the precision-grip hand, the brain was more ape-like.

Biochemical cell signals quantified for first time: Just as cell phones and computers transmit data through electronic networks, the cells of your body send and receive chemical messages through molecular pathways. The term “cell signaling” was coined more than 30 years ago to describe this process. Now, for the first time, physicists have quantified the data capacity of a biochemical signaling pathway and found a surprise – it’s way lower than even an old-fashioned, dial-up modem.


Mummies tell history of a modern plague: Mummies from along the Nile are revealing how age-old irrigation techniques may have boosted the plague of schistosomiasis, a water-borne parasitic disease that infects an estimated 200 million people today. An analysis of the mummies provides details about the prevalence of the disease across populations in ancient times, and how human alteration of the environment may have contributed to its spread.

Polar dinosaur tracks open new trail to past: Paleontologists discovered a group of more than 20 polar dinosaur tracks on the coast of Victoria, Australia, offering a rare glimpse into animal behavior during the last period of pronounced global warming, about 105 million years ago. The discovery is the largest and best collection of polar dinosaur tracks ever found in the Southern Hemisphere.


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Beer, bugs and brains: Hot topics in 2010
2010: A science odyssey