Aside from the first, short introductory article, I'm sharing the beginning of each one - follow the title links to read the whole piece.
A three-part series on the scientific struggle to explain the conscious self
Web edition : Monday, February 6th, 2012The human brain is very good at figuring things out, except about itself.Consciousness has posed a special challenge to scientists, but new ways of studying the brain may finally yield a deeper understanding. Science News describes the latest thinking on consciousness in this three-part special report.
Think about it. A brain capable of sophisticated reasoning has to be very complicated — so complicated that it would take an even more sophisticated brain to figure out how it works. But an even more sophisticated brain would be even harder to figure out. As the brain gets smarter and smarter, and thus more and more complex, it becomes ever more difficult to explain how it works. The brain can never catch up. Human brains are amazing devices, just not amazing enough to explain all of their amazing abilities.
In truth, the human brain has figured out a lot about how it works. Much of the molecular and cellular machinery underlying thinking and learning and memory, and even emotion, has been outlined in elaborate detail. But dissecting the machinery has not enabled scientists to say why the machine has a persistent sense of itself, how it generates the feeling of self-awareness (and even the awareness of that self-awareness) that people generally refer to as consciousness.
For millennia, philosophers have grappled with consciousness, trying to discern the distinction between mind and body or to show that such a distinction is illusory. But only in the present millennium have scientists engaged these arguments in a serious way, equipped with substantial scientific data.
Science News neurocience writer Laura Sanders has explored the latest efforts by consciousness researchers to demystify the mind and reports her findings in a three-part series. Her account describes how consciousness, long regarded by neuroscientists as a taboo topic, has finally emerged as a legitimate realm of scientific inquiry. Research results have begun accumulating, and theorists have begun transforming explanations of consciousness from philosophical speculations into quantitative concepts and equations.
A common thread connecting much consciousness theorizing is the role of information. Using the mathematics of information theory, scientists have begun to get a grip on possible ways of measuring consciousness, making it easier to identify and perhaps, someday, easier to create in a non-biological information-processing system. The prospect of a conscious computer may be terrifying to fans of the Terminator films (or, for older people, Colossus: The Forbin Project). But it would nevertheless be interesting to see if a conscious machine would be sufficiently sophisticated to figure out for itself how it works. —Tom Siegfried, Editor in Chief
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Brain signatures lead scientists to the seat of consciousness
February 11th, 2012; Vol.181 #3 (p. 22)This article is part of Demystifying the Mind, a special report on the new science of consciousness. The next installments will appear in the February 25 and March 10 issues of Science News.Michael Morgenstern
Humankind’s sharpest minds have figured out some of nature’s deepest secrets. Why the sun shines. How humans evolved from single-celled life. Why an apple falls to the ground. Humans have conceived and built giant telescopes that glimpse galaxies billions of light-years away and microscopes that illuminate the contours of a single atom. Yet the peculiar quality that enabled such flashes of scientific insight and grand achievements remains a mystery: consciousness.
Though in some ways deeply familiar, consciousness is at the same time foreign to those in its possession. Deciphering the cryptic machinations of the brain — and how they create a mind — poses one of the last great challenges facing the scientific world.
For a long time, the very question was considered to be in poor taste, acceptable for philosophical musing but outside the bounds of real science. Whispers of the C-word were met with scorn in polite scientific society.
Toward the end of the last century, though, sentiment shifted as some respectable scientists began saying the C-word out loud. Initially these discussions were tantalizing but hazy: Like kids parroting a dirty word without knowing what it means, scientists speculated on what consciousness is without any real data. After a while, though, researchers developed ways to turn their instruments inward to study the very thing that was doing the studying.
Today consciousness research has become a passion for many scientists, and not just for the thrill of saying a naughty word. A flood of data is sweeping brain scientists far beyond their intuitions, for the first time enabling meaningful evidence-based discussions about the nature of consciousness.
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The loopy nature of consciousness trips up scientists studying themselves
February 11th, 2012; Vol.181 #3 (p. 28)
This essay is part of Demystifying the Mind, a special report on the new science of consciousness. The next installments will appear in the February 25 and March 10 issues of Science News.
When Francis Crick decided to embark on a scientific research career, he chose his specialty by applying the “gossip test.” He’d noticed that he liked to gossip about two especially hot topics in the 1940s — the molecular basis for heredity and the mysteries of the brain. He decided to tackle biology’s molecules first. By 1953, with collaborator James Watson (and aided by data from competitor Rosalind Franklin), Crick had identified the structure of the DNA molecule, establishing the foundation for modern genetics.
A quarter century later, he decided it was time to try the path not taken and turn his attention to the brain — in particular, the enigma of consciousness.
At first, Crick believed the mysteries of consciousness would be solved with a striking insight, similar to the way the DNA double helix structure explained heredity’s mechanisms. But after a while he realized that consciousness posed a much tougher problem. Understanding DNA was easier because it appeared in life’s history sooner; the double helix template for genetic replication marked the beginning of evolution as we know it. Consciousness, on the other hand, represented evolution’s pinnacle, the outcome of eons of ever growing complexity in biochemical information processing.
“The simplicity of the double helix … probably goes back to near the origin of life when things had to be simple,” Crick said in a 1998 interview. “It isn’t clear there will be a similar thing in the brain.”
In fact, it has become pretty clear that deciphering consciousness will definitely be more difficult than describing the dynamics of DNA.
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Somewhere along a tangled path, sights, sounds and insights pop into awareness
February 25th, 2012; Vol.181 #4 (p. 18)Demystifying the MindMichael Morgenstern
This feature is the second installment in a three-part series on the scientific struggle to explain consciousness. To read the previous installment and see what’s in the next issue, click here.
In one of science’s most iconic moments, Isaac Newton’s eye caught the red glint of an apple as it plunged toward the ground. He heard the leaves rustle in the light breeze and felt the warmth of the tea he was drinking at the time.
These sensory inputs streamed into his brain, where they met his vast stores of knowledge, his internal musings, his peculiar brand of curiosity and perhaps even a fond recollection of escaping the ground’s hold while climbing a tree as a boy. All at once, sights, sounds, emotions and memories converged to form a whole, rich experience in the garden that day.
It was this fortuitous experience — perfectly ripe for a big idea — that (legend has it) caused Newton to wonder why the apple fell not sideways or even upward, but straight down. Inspiration struck, ushering in a new understanding of gravity.
Newton gets the glory for figuring out that the same mysterious force pulls planets toward the sun and apples toward Earth, but how he did it hinges on an even deeper mystery: How his brain created a single, seamless experience from a chaotic flux of internal and external messages.
And that mystery isn’t confined to brains like Newton’s. In all conscious people, the brain somehow gives meaning to the external environment, allowing for thought, self-reflection and discovery. “It’s not that conscious experience is one little interesting phenomenon,” says neuroscientist Ralph Adolphs of Caltech. “It’s literally the whole world.”
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Demystifying the MindMichael Morgenstern
This feature is the final installment in a three-part series on the scientific struggle to explain consciousness. To read the entire series, click here.
As a scientist, Giulio Tononi’s goal is as lofty as it gets: He wants to understand how the brain generates consciousness. In his hunt, he and colleagues at the University of Wisconsin–Madison routinely use state-of-the-art brain scanners to produce torrents of information that stream into sophisticated computer programs describing various aspects of brain function.
But Tononi’s most profound insight didn’t spring from this huge cache of scientific data. It came instead from a moment of quiet reflection. When he stepped away from his scanners and data and the hustle of the lab and thought — deeply — about what it was like to be conscious, he realized something: Each split second of awareness is a unified, holistic experience, completely different from any experience before or after it.
From that observation alone, Tononi intuited a powerful new theory of consciousness, a theory based on the flow of information. He and others believe that mathematics — in particular, a set of equations describing how bits of data move through the brain — is the key to explaining how the mind knits together an experience.
Because of its clarity, this informational intuition has resonated with other researchers, inspiring a new way to see the consciousness problem. “This insight was very important to me,” says Anil Seth of the Sackler Centre for Consciousness Science at the University of Sussex in Brighton, England. “I thought, there’s something right about all this.”
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