NEAR-DEATH EXPERIENCES EXPLAINED

brent.dunn@jefferson.kyschools.us

photo: iStockPhoto

Do you believe in life after death?

Many people believe in ghosts and heaven, and about three in 100 Americans report actually having near-death experiences. These typically include an awareness of being dead, out-of-body experiences, meeting dead people, entering tunnels of light, and so on.

But these are stories and anecdotes; what does science have to say?

A new article published in Trends in Cognitive Sciences by neuroscientist Dean Mobbs, of the University of Cambridge's Medical Research Council Cognition and Brain Sciences Unit, and Caroline Watt, of the University of Edinburgh, finds that "contrary to popular belief, research suggests that there is nothing paranormal about these experiences. Instead, near-death experiences are the manifestation of normal brain function gone awry, during a traumatic, and sometimes harmless, event."

Mobbs and Watt noted that many classic NDE symptoms are actually reported by people who were never in danger of dying in the first place. This suggests that the perception that one is near death is traumatic and disturbing enough to cause some of the experiences.

Researcher Susan Blackmore, author of Dying to Live: Near-Death Experiences (Prometheus Books, 1993), notes that many NDEs (such as euphoria and the feeling of moving toward a tunnel of white light) are common symptoms of oxygen deprivation in the brain.

The new paper also discussed something called "walking corpse" syndrome, named after French neurologist Jules Cotard. Co-author Watt told Discovery News, "The sufferer feels that he or she is dead, even though not actually near death. It can be associated with trauma and some illnesses. It's not fully understood why individuals suffer from Cotard syndrome, but one possibility is that it's the brain's attempt to make sense of the strange experiences that the patient is having.

"This is relevant to NDEs because the near-death experience may also arise out of an attempt to interpret unusual physiological and psychological experiences, and the NDE includes the perception that one is not alive in the normal sense of the word."

Watt's research also busts another myth: that people have "returned from the dead" -- if by dead you mean clinical brain death.

No one has survived true clinical death (which is why the experiences are called near-death). Many people have been revived after their heart stopped for short periods of time -- around 20 minutes or more -- but anyone revived from brain death would be permanently and irreparably brain damaged and certainly unable to report their experiences.

"The idea of surviving clinical brain death is mythical," Watt said. "NDEs are sometimes reported after a person experiences some of the preliminary 'stages' of death -- for instance, when the heart stops beating for a while and the person is then revived. I think it's curious, however, that a survey has shown that 82 percent of individuals who have survived being actually near death do not report a near-death experience. That would seem to undermine the idea that these experiences give a glimpse into life after death."

Watt believes that near-death experiences hold an enduring fascination for people because they like the idea that humans survive bodily death.

"Some people find this a comforting idea," Watt said, "because it suggests we are not simply like other biological organisms on our planet."

The fact that near-death experiences can be chemically induced and explained by neurological mechanisms suggests a natural -- instead of supernatural -- cause.

Woolly Mammoth DNA Successfully Spliced Into Elephant Cells

A group of researchers are getting closer to bringing the extinct woolly mammoth back to life. Geneticist George Church’s lab at Harvard University successfully copied genes from frozen woolly mammoths and pasted them into the genome of an Asian elephant.

Using a DNA editing tool called CRISPR, the scientists spliced genes for the mammoths’ small ears, subcutaneous fat, and hair length and color into the DNA of elephant skin cells. The tissue cultures represent the first time woolly mammoth genes have been functional since the species went extinct around 4,000 years ago.

The research has not yet been peer-reviewed or published in a scientific journal “because there is more work to do,” Church told the U.K.’s Sunday Times, “but we plan to do so.”

The work is part of an effort to bring extinct species back from the dead, a process called “de-extinction”. The recent breakthrough shows that one proposed de-extinction method--which involves splicing genes from extinct animals into the genomes of their living relatives--just might work. But don't believe the headlines suggesting woolly mammoth cloning is just around the corner. Church explained to Popular Science that there’s a lot more research to be done.

“Just making a DNA change isn’t that meaningful,” says Church. “We want to read out the phenotypes.” To do that, the team needs to figure out how to take the flat hybrid cells from a petri dish and coax them into becoming specialized tissues--such as blood cells or liver organoids--then test to see if they behave properly. For example, do the mammoth hair genes lead to hair that's the right color, length, and woolliness?

If those tests go well, the team hopes to turn the elephant/mammoth skin cells into hybrid embryos that can be grown in artificial wombs, devices that allow for pregnancies outside of an animal's uterus. Artificial wombs are pretty speculative at this point, but the alternative--implanting the hybrids into the wombs of female elephants--is unsavory to animal rights activists as well as geneticists. “It’s going to be more humane and easier if we can set up hundreds of [embryos] in an incubator and run tests,” says Church.

If they can get the hybrid creatures to survive, the project's first goal will be to engineer an elephant that can survive in cold temperatures. The team thinks that expanding the elephant’s range into colder climates could help keep it away from humans and the conflicts that are threatening to make Asian and African elephants extinct. Later, after the engineered elephants gain a foothold, Church says the team will try to revive the mammoths by integrating higher amounts of mammoth DNA into the hybrids.

Of course, it's possible the mammoth genome will never be completely reconstructed, and the creatures will only remain elephant/mammoth hybrids. But if it looks like a mammoth and fulfills the same ecological functions as a mammoth, is it a mammoth? What even is a mammoth, anyway?

Scientists Resurrect Bonkers Extinct Frog That Gives Birth Through Its Mouth

It's been gone since 1983, but the Lazarus Project has brought it back to life. Gastric-Brooding Frog Australian Government Department of the Environment, Water, Heritage and the Arts In 1983, the world lost one of its weirdest frogs. The gastric-brooding frog, native to tiny portions of Queensland, Australia, gave birth through its mouth, the only frog to do so (in fact, very few other animals in the entire animal kingdom do this--it's mostly this frog and a few fish). It succumbed to extinction due to mostly non-human-related causes--parasites, loss of habitat, invasive weeds, a particular kind of fungus. There were two subspecies, the northern and souther gastric-brooding frog, and they both became extinct in the mid-80s sometime. Except--what if they didn't? Taking place at the University of Newcastle, the quest to revive the gastric-brooding frog became known as the Lazarus Project. Using somatic-cell nuclear transfer (SCNT), a method for cloning, the project has achieved the major step forward of creating an early embryo of the extinct frog. Essentially, they found a related frog--the great barred frog, which also lives in Queensland and has cool eye markings, like it's wearing sunglasses--deactivated its eggs, and replaced them with eggs taken from the extinct frog. Even though the gastric-brooding frog has been extinct for decades, it's possible to do this because individual specimens were kept preserved in, believe it or not, everyday deep freezers. When going through somatic-cell nuclear transfer, the eggs began to divide and form into the early embryo stage. The embryos didn't survive much longer than that, but it was confirmed that these embryos contain genetic information from the gastric-brooding frog--that yes, in fact, they have brought it back to life. The researchers are confident that this is a "technical, not biological" problem at this stage to breed gastric-brooding frogs to adulthood. This is a big step forward for the worldwide attempts to revive extinct animals--the Lazarus Project researchers will soon meet with those working to revive the woolly mammoth, dodo, and other extinct beasties to share what they've learned. Oh, and in case you were wondering: the gastric-brooding frog lays eggs, which are coated in a substance called prostaglandin. This substance causes the frog to stop producing gastric acid in its stomach, thus making the frog's stomach a very nice place for eggs to be. So the frog swallows the eggs, incubates them in her gut, and when they hatch, the baby frogs crawl out her mouth. How delightfully weird!

FLY PARASITE TURNS HONEY BEES INTO 'ZOMBIES' The parasites that cause the transformation may provide a clue to the mysterious colony collapse disorder

American scientists have discovered that a fly parasite can turn honey bees into confused zombies before killing them, in an advance that could offer new clues to why bee colonies are collapsing.

So far, the parasite has only been detected in honey bees in California and South Dakota, American researchers reported in the open access science journal PLoS ONE this week.


But if it turns out to be an emerging parasite, that "underlines the danger that could threaten honey bee colonies throughout North America," said the study led by San Francisco State University professor of biology John Hafernik.

Hafernik made the discovery by accident, when he foraged some bees from outside a light fixture at the university to feed to a praying mantis he'd brought back from a field trip.

"But being an absent-minded professor, I left them in a vial on my desk and forgot about them. Then the next time I looked at the vial, there were all these fly pupae surrounding the bees," he said.

Soon, the bees began to die, but not in the usual way by sitting still and curling up. These bees kept trying to move their legs and get around, but they were too weak, said lead author Andrew Core, a graduate student in Hafernik's lab.

"They kept stretching them out and then falling over," said Core. "It really painted a picture of something like a zombie."

Further study showed that bees that left their hives at night were most likely to become infected with the fly parasite, identified as Apocephalus borealis.

Once bees were parasitized by the fly, they would abandon their hives and congregate near lights, a very unusual behavior for bees.


"When we observed the bees for some time -- the ones that were alive -- we found that they walked around in circles, often with no sense of direction," said Core.

The parasite lays its eggs in the bee's abdomen. About a week after the bee dies, the fly larvae push their way into the world, often exiting from between the bee's head and mid-section.

The research, which has also confirmed that the same flies have been parasitizing bumblebees, won local excellence awards when it was first presented last year.

Next, the team hopes to find out more about where the parasitization is taking place, and whether the "zombie bees" leave the colony of their own accord or if their disease is sensed by comrades who then push them out.

Researchers plan to use tiny radio tags and video monitoring to find clues to the mystery.

"We don't know the best way to stop parasitization, because one of the big things we're missing is where the flies are parasitizing the bees," Hafernik said.

"We assume it's while the bees are out foraging, because we don't see the flies hanging around the bee hives. But it's still a bit of a black hole in terms of where it's actually happening."

Experts have theorized that the huge die-off of bees worldwide since 2006, a major threat to crops that depend on the honey-making insects for pollination, is not due to any one single factor.

Parasites, viral and bacterial infections, pesticides, and poor nutrition resulting from the impact of human activities on the environment have all played a role in the decline.

The mysterious decimation of bee populations in the United States, Europe, Japan and elsewhere in recent years threatens agricultural production worth tens of billions of dollars.