Posts Tagged ‘ Brain ’

The Struggle for the (Possible) Soul of David Eagleman

Robert Jensen in Killing the Buddha:

A neuroscientist imagines life beyond the brain.

There’s a struggle inside the brain of David Eagleman for the soul of David Eagleman.

That is, there might be such a struggle if Eagleman’s brain believed that Eagleman had a soul, which he is not sure about. In fact, Eagleman’s brain is not completely sure that there is an Eagleman-beyond-Eagleman’s-brain at all—with or without a soul, whatever that term might mean.

Welcome to the world of “possibilian” neuroscientist-writer David Eagleman, to life in the space between what-is and what-if, between the facts we think we know and the fictions that illuminate what we don’t know.

Eagleman-the-scientist would love to rev up his high-tech neuroimaging machines to answer the enduring questions about the brain and the mind, the body and the soul. But Eagleman-the-writer knows that those machines aren’t going to answer those questions.

Eagleman rejects not only conventional religion but also the labels of agnostic and atheist. In their place, he has coined the term possibilian: a word to describe those who “celebrate the vastness of our ignorance, are unwilling to commit to any particular made-up story, and take pleasure in entertaining multiple hypotheses.”

Taking seriously the old saying “the absence of proof isn’t the proof of absence,” Eagleman recognizes that people who don’t believe in God (at least not in God defined as a supernatural force or entity) can never say with certainty what doesn’t exist. So, the difference between agnostic and atheist is typically a matter of attitude, and such is the case with adding possibilian to the mix. Eagleman is not trying to support or rule out any particular claim but simply suggesting that it’s healthy to imagine possibilities.

While he reports on what-is in scientific journals, Eagleman’s brain and mind run free pondering the what-ifs. In his 2009 book Sum: Forty Tales from the Afterlives, Eagleman imagines life beyond death, in a playful series of short philosophical musings: What if there were an afterlife in which we relive all our experiences but shuffled into a new order? What if in an afterlife we confront all the possible versions of ourselves that could have been? What if we experience death in stages: when the body stops functioning, when we’re buried, and the moment when your name is spoken by another for the last time? Sum offers 40 such what-ifs. The stories aren’t meant as serious proposals about what an afterlife may be. They are vehicles for Eagleman’s ruminations on the vexing philosophical questions of human life.

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Lost Sleep Is Hard to Find

Erin O’Donnell in Harvard Magazine:

it’s a time-honored practice among medical residents, cramming undergrads, and anyone else burning the candle at both ends: get very little sleep for days, maybe even pull an all-nighter, and then crash for an extra-long night of shut-eye to catch up.

Ten hours of sleep at once may indeed recharge us, and allow us to perform well for several hours after waking, according to research recently published inScience Translational Medicine. But “the brain literally keeps track of how long we’ve been asleep and awake—for weeks,” says Harvard Medical School (HMS) neurology instructor Daniel A. Cohen, M.D., lead author of the study. And that means that the bigger our aggregate sleep deficit, the faster our performance deteriorates, even after a good night’s rest.

Cohen and his coauthors monitored nine young men and women who spent three weeks on a challenging schedule: awake for 33 hours, asleep for 10—the equivalent of 5.6 hours of sleep a day. (This approximates the schedule of a medical resident, but many of us live under similar conditions; the National Sleep Foundation reports that 16 percent of Americans sleep six or fewer hours a night.) When the study participants were awake, they took a computer-based test of reaction time and sustained attention every four hours.

The researchers were surprised to discover just how much an extended rest boosted test performance. “Even though people were staying awake for almost 33 hours, when they had the opportunity to sleep for 10 hours, their performance shortly after waking was back to normal,” Cohen says. “The really interesting finding here is that there’s a short-term aspect of sleep loss that can be made up relatively quickly, within a long night.”

But the days and weeks of lost sleep eventually took their toll. The investigators knew from previous research that people awake for 24 hours straight display reaction times comparable to those of people who are legally drunk. Cohen’s new study reveals that those who pull an all-nighter on top of two or three weeks of chronic sleep loss reach that level of severe impairment faster—after just 18 hours awake.

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How facts backfire

Joe Keohane in The Boston Globe:

It’s one of the great assumptions underlying modern democracy that an informed citizenry is preferable to an uninformed one. “Whenever the people are well-informed, they can be trusted with their own government,” Thomas Jefferson wrote in 1789. This notion, carried down through the years, underlies everything from humble political pamphlets to presidential debates to the very notion of a free press. Mankind may be crooked timber, as Kant put it, uniquely susceptible to ignorance and misinformation, but it’s an article of faith that knowledge is the best remedy. If people are furnished with the facts, they will be clearer thinkers and better citizens. If they are ignorant, facts will enlighten them. If they are mistaken, facts will set them straight.

In the end, truth will out. Won’t it?

Maybe not. Recently, a few political scientists have begun to discover a human tendency deeply discouraging to anyone with faith in the power of information. It’s this: Facts don’t necessarily have the power to change our minds. In fact, quite the opposite. In a series of studies in 2005 and 2006, researchers at the University of Michigan found that when misinformed people, particularly political partisans, were exposed to corrected facts in news stories, they rarely changed their minds. In fact, they often became even more strongly set in their beliefs. Facts, they found, were not curing misinformation. Like an underpowered antibiotic, facts could actually make misinformation even stronger.

This bodes ill for a democracy, because most voters — the people making decisions about how the country runs — aren’t blank slates. They already have beliefs, and a set of facts lodged in their minds. The problem is that sometimes the things they think they know are objectively, provably false. And in the presence of the correct information, such people react very, very differently than the merely uninformed. Instead of changing their minds to reflect the correct information, they can entrench themselves even deeper.

“The general idea is that it’s absolutely threatening to admit you’re wrong,” says political scientist Brendan Nyhan, the lead researcher on the Michigan study. The phenomenon — known as “backfire” — is “a natural defense mechanism to avoid that cognitive dissonance.”

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Michelangelo’s secret message in the Sistine Chapel: A juxtaposition of God and the human brain

R. Douglas Fields in Scientific American:

At the age of 17 he began dissecting corpses from the church graveyard. Between the years 1508 and 1512 he painted the ceiling of the Sistine Chapel in Rome. Michelangelo Buonarroti—known by his first name the world over as the singular artistic genius, sculptor and architect—was also an anatomist, a secret he concealed by destroying almost all of his anatomical sketches and notes. Now, 500 years after he drew them, his hidden anatomical illustrations have been found—painted on the ceiling of the Sistine Chapel, cleverly concealed from the eyes of Pope Julius II and countless religious worshipers, historians, and art lovers for centuries—inside the body of God.

This is the conclusion of Ian Suk and Rafael Tamargo, in their paper in the May 2010 issue of the scientific journalNeurosurgery. Suk and Tamargo are experts in neuroanatomy at the Johns Hopkins University School of Medicine in Baltimore, Maryland. In 1990, physician Frank Meshberger published a paper in the Journal of the American Medical Association deciphering Michelangelo’s imagery with the stunning recognition that the depiction in God Creating Adam in the central panel on the ceiling was a perfect anatomical illustration of the human brain in cross section. Meshberger speculates that Michelangelo surrounded God with a shroud representing the human brain to suggest that God was endowing Adam not only with life, but also with supreme human intelligence. Now in another panel The Separation of Light from Darkness (shown at left), Suk and Tamargo have found more. Leading up the center of God’s chest and forming his throat, the researchers have found a precise depiction of the human spinal cord and brain stem.

Is the ceiling of the Sistine Chapel a 500 year-old puzzle that is only now beginning to be solved? What was Michelangelo saying by construction the voice box of God out of the brain stem of man? Is it a sacrilege or homage?

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The Memory Doctor

William Saletan in Slate:

Part I: The Ministry of Truth

In 1984, George Orwell told the story of Winston Smith, an employee in the propaganda office of a totalitarian regime. Smith’s job at the fictional Ministry of Truth was to destroy photographs and alter documents, remaking the past to fit the needs of the present. But 1984 came and went, along with Soviet communism. In the age of the Internet, nobody could tamper with the past that way. Could they?

Yes, we can. In fact, last week, Slate did.

We took the Ministry of Truth as our model. Here’s how Orwell described its work:

As soon as all the corrections which happened to be necessary in any particular number of The Times had been assembled and collated, that number would be reprinted, the original copy destroyed, and the corrected copy placed on the files in its stead. This process of continuous alteration was applied not only to newspapers, but to books, periodicals, pamphlets, posters, leaflets, films, sound-tracks, cartoons, photographs—to every kind of literature or documentation which might conceivably hold any political or ideological significance. Day by day and almost minute by minute the past was brought up to date. In this way every prediction made by the Party could be shown by documentary evidence to have been correct, nor was any item of news, or any expression of opinion, which conflicted with the needs of the moment, ever allowed to remain on record. All history was a palimpsest, scraped clean and reinscribed exactly as often as was necessary. In no case would it have been possible, once the deed was done, to prove that any falsification had taken place.

Slate can’t erase all records the way Orwell’s ministry did. But with digital technology, we can doctor photographs more effectively than ever. And that’s what we did in last week’sexperiment. We altered four images from recent political history, took a fifth out of context, and mixed them with three unadulterated scenes. We wanted to test the power of photographic editing to warp people’s memories.

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Lost? Evidence That Sense Of Direction Is Innate

Katherine Harmon in Scientific American:

Not everyone has a perfect sense of direction, whether they would like to admit it or not. But two new studies have found that even baby rats have a basic spatial framework in their brains ready to use as soon as they leave the nest for the first time—which is much earlier than had previously been documented.

The findings reveal that not all sense of space is learned. They show that at least some of that sense is innate, “that the basic constituents of the cognitive map develop independently of spatial experience or might even precede it,” noted the authors of one of the new studies, both published online June 17 in Science.

For the two independent studies researchers record rats’ neuronal firings as soon as newborn pups opened their eyes and began to explore their surroundings. Both teams were surprised to find adult-level cell function in some of the directional regions.

At this age, “the animals would not yet have had a chance to explore the environment beyond their nest,”Francesca Cacucci, a researcher at the Institute of Behavioral Neuroscience at University College London and co-author of one of the papers, writes in an e-mail. “This suggests strongly that sense of direction is independent of spatial experience.”

And because the mammalian hippocampus is relatively consistent in its make-up across species, these lab rat–based findings likely mirror a similar developmental trajectory in humans.

Other abilities, such as face perception or language use, are thought to be innate. But “space is such a basic cognitive function, and to have it be partly innate is really interesting and groundbreaking work,” says Linda Palmer, a project scientist at the Department of Anatomy and Neurobiology at the University of California, Irvine, who coauthored a perspectives essay accompanying the two studies in Science.

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The Trouble With Intuition

Daniel J. Simons and Christopher F. Chabris in The Chronicle of Higher Education:

“How do I love thee? Let me count the ways.” Those lines by Elizabeth Barrett Browning, written while she was being courted by Robert Browning, and among the most famous in all of poetry, open one of 44 of her love poems that are collectively known as Sonnets From the Portuguese. The Sonnets were first published in book form in 1850, as part of the second edition of her collected poems. At least that’s what poetry scholars and bibliophiles thought for several decades until Thomas J. Wise announced that he had discovered a previously unknown earlier printing.

Wise was a celebrated British collector of rare books and manuscripts in the late 19th and early 20th centuries; the catalog of his private library filled 11 volumes. In 1885 an author named W.C. Bennett showed Wise several copies of a 47-page, privately printed pamphlet of the Sonnetsdated 1847 and marked “not for publication.” Private printings of literature were not unusual in that era. What was unusual was the discovery of a previously unknown collection of such important poetry that predated the first known public printing. Wise immediately recognized the rarity and value of the pamphlets, and bought one for £10 (about $1,200 today). Over the ensuing years, Wise discovered other previously unknown collections of minor works by major authors, including some by Alfred Tennyson, Charles Dickens, and Robert Louis Stevenson. Collectors and libraries snapped up those volumes, and Wise’s fame and wealth grew.

At first glance, Wise’s items seemed authentic, especially to a buyer considering just one pamphlet at a time. Each one fit nicely with the rest of its author’s body of work. For example, the date of Browning’s private printing of the Sonnets corresponded with a gap of four years between when the poems were finished and when they were officially published. The pamphlets also appeared to be authentic in format and typography—just how an expert would expect them to look and feel. Although the steady stream of new discoveries by Wise did raise isolated suspicions that something might be amiss, the pamphlets he distributed were broadly respected as genuine for decades.

Some 45 years after Wise found the private edition of the Sonnets, two British book dealers, named John Carter and Graham Pollard, decided to investigate his finds. They re-examined the Browning volume and identified eight reasons why its existence was inconsistent with typical practices of the era. For example, none of the copies had been inscribed by the author, none were trimmed and bound in the customary way, and the Brownings never mentioned the special private printing in any letters, memoirs, or other documents.

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