Links for Keyword: Consciousness
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By Laura Sanders 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.” © Society for Science & the Public 2000 - 2012
By Laura Sanders 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.” © Society for Science & the Public 2000 - 2012
By Antonio Damasio, Special to CNN (CNN) -- How do living organisms become conscious of what is happening to them and around them? How is it that I as well as you, reader of these words, can be conscious of our respective existences and of what is going on in our minds — in my case, ideas about how the brain generates consciousness, about the fact that I was asked to prepare this particular text for a specific deadline, along with the fact that I happen to be in Paris, at the moment, not Los Angeles, and that I am writing this on a cold January day. The biological mechanisms behind the phenomena of consciousness remain unclear although it is fair to say that recently our understanding has made remarkable progress. What are we are certain of understanding and where is it that our understanding fails? On the side of understanding, we can point to the process of sensory representation as an important part of consciousness. Most of what we are conscious of (conceivably all that we are conscious of) consists of representations of objects and events in the sensory modalities in which our brains trade, for example, vision, hearing, touching, smelling, taste, sensing the state of our body's interior. Mapping, in other words. Our brains, at all the levels of their organization, are inveterate makers of maps, simple and not so simple, and as far as I can gather, we only become conscious of the things and actions that the sensory systems help us map. CNN© 2012 Cable News Network.
Christof Koch We moderns believe that our momentary, subjective experience is intimately linked to events in the brain. One set of neurons fires, and we perceive an apple's colour, while a different population of cells gives rise to its taste. Yet the self is also stable: turn the brain off, as happens during heart surgery when the body is cooled to frigid temperatures, and on recovery, the patient's character, personality, habits and long-term memories remain intact. It is these stable aspects of the self, rather than the ebb and flow of our thoughts and percepts, that physicist-turned-neuroscientist Sebastian Seung seeks to explain in Connectome. Seung argues intelligently and powerfully that the self lies in the totality of the brain's wiring — the eponymous 'connectome', the word used by neuroscientists to denote all the fibre bundles (the white matter) of the human brain. These insulated nerve axons have a total length of around 150,000 kilometres. Seung hails a new science, 'connectomics', as the key to understanding the brain and its pathologies. This view is grounded in a older doctrine known as connectionism, which postulates that neurons are simple devices and that their connections determine their functions. Cataloguing the links among neurons therefore charts the mind. The heart of Connectome deals with how nervous systems can be reconstructed using electron microscopy. To do this, neural tissue is cut into slices 40–50 nanometres thick, and then imaged to a resolution of a few nanometres. Imaging 1 cubic millimetre of cortex generates 1 petabyte of data, or about a billion photo images from a typical digital camera. © 2012 Nature Publishing Group,
By Laura Sanders 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. © Society for Science & the Public 2000 - 2012
By Tom Siegfried 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.” © Society for Science & the Public 2000 - 2012