Document (#41562)

Author

Koch, C.

Title

Consciousness : confessions of a romantic reductionist

Imprint

Cambridge, Massachusetts : MIT Press

Year

2012

Pages

xii, 181 S

Isbn

978-0-262-01749-7

Abstract

What links conscious experience of pain, joy, color, and smell to bioelectrical activity in the brain? How can anything physical give rise to nonphysical, subjective, conscious states? Christof Koch has devoted much of his career to bridging the seemingly unbridgeable gap between the physics of the brain and phenomenal experience. This engaging book?part scientific overview, part memoir, part futurist speculation?describes Koch's search for an empirical explanation for consciousness. Koch recounts not only the birth of the modern science of consciousness but also the subterranean motivation for his quest?his instinctual (if "romantic") belief that life is meaningful. Koch describes his own groundbreaking work with Francis Crick in the 1990s and 2000s and the gradual emergence of consciousness (once considered a "fringy" subject) as a legitimate topic for scientific investigation. Present at this paradigm shift were Koch and a handful of colleagues, including Ned Block, David Chalmers, Stanislas Dehaene, Giulio Tononi, Wolf Singer, and others. Aiding and abetting it were new techniques to listen in on the activity of individual nerve cells, clinical studies, and brain-imaging technologies that allowed safe and noninvasive study of the human brain in action. Koch gives us stories from the front lines of modern research into the neurobiology of consciousness as well as his own reflections on a variety of topics, including the distinction between attention and awareness, the unconscious, how neurons respond to Homer Simpson, the physics and biology of free will, dogs, Der Ring des Nibelungen, sentient machines, the loss of his belief in a personal God, and sadness. All of them are signposts in the pursuit of his life's work?to uncover the roots of consciousness

Content

In which I introduce the ancient mind-body problem, explain why I am on a quest to use reason and empirical inquiry to solve it, acquaint you with Francis Crick, explain how he relates to this quest, make a confession, and end on a sad note -- In which I write about the wellsprings of my inner conflict between religion and reason, why I grew up wanting to be a scientist, why I wear a lapel pin of Professor Calculus, and how I acquired a second mentor late in life -- In which I explain why consciousness challenges the scientific view of the world, how consciousness can be investigated empirically with both feet firmly planted on the ground, why animals share consciousness with humans, and why self-consciousness is not as important as many people think it is -- In which you hear tales of scientist-magicians that make you look but not see, how they track the footprints of consciousness by peering into your skull, why you don't see with your eyes, and why attention and consciousness are not the same -- In which you learn from neurologists and neurosurgeons that some neurons care a great deal about celebrities, that cutting the cerebral cortex in two does not reduce consciousness by half, that color is leached from the world by the loss of a small cortical region, and that the destruction of a sugar cube-sized chunk of brain stem or thalamic tissue leaves you undead -- In which I defend two propositions that my younger self found nonsense--you are unaware of most of the things that go on in your head, and zombie agents control much of your life, even though you confidently believe that you are in charge -- In which I throw caution to the wind, bring up free will, Der ring des Nibelungen, and what physics says about determinism, explain the impoverished ability of your mind to choose, show that your will lags behind your brain's decision, and that freedom is just another word for feeling -- In which I argue that consciousness is a fundamental property of complex things, rhapsodize about integrated information theory, how it explains many puzzling facts about consciousness and provides a blueprint for building sentient machines -- In which I outline an electromagnetic gadget to measure consciousness, describe efforts to harness the power of genetic engineering to track consciousness in mice, and find myself building cortical observatories -- In which I muse about final matters considered off-limits to polite scientific discourse: to wit, the relationship between science and religion, the existence of God, whether this God can intervene in the universe, the death of my mentor, and my recent tribulations.

Footnote

Rez. in: The New York Review of Books, 10.01.2013 ( J. Searle): "The problem of consciousness remains with us. What exactly is it and why is it still with us? The single most important question is: How exactly do neurobiological processes in the brain cause human and animal consciousness? Related problems are: How exactly is consciousness realized in the brain? That is, where is it and how does it exist in the brain? Also, how does it function causally in our behavior? To answer these questions we have to ask: What is it? Without attempting an elaborate definition, we can say the central feature of consciousness is that for any conscious state there is something that it feels like to be in that state, some qualitative character to the state. For example, the qualitative character of drinking beer is different from that of listening to music or thinking about your income tax. This qualitative character is subjective in that it only exists as experienced by a human or animal subject. It has a subjective or first-person existence (or "ontology"), unlike mountains, molecules, and tectonic plates that have an objective or third-person existence. Furthermore, qualitative subjectivity always comes to us as part of a unified conscious field. At any moment you do not just experience the sound of the music and the taste of the beer, but you have both as part of a single, unified conscious field, a subjective awareness of the total conscious experience. So the feature we are trying to explain is qualitative, unified subjectivity.
Now it might seem that is a fairly well-defined scientific task: just figure out how the brain does it. In the end I think that is the right attitude to have. But our peculiar history makes it difficult to have exactly that attitude-to take consciousness as a biological phenomenon like digestion or photosynthesis, and figure out how exactly it works as a biological phenomenon. Two philosophical obstacles cast a shadow over the whole subject. The first is the tradition of God, the soul, and immortality. Consciousness is not a part of the ordinary biological world of digestion and photosynthesis: it is part of a spiritual world. It is sometimes thought to be a property of the soul and the soul is definitely not a part of the physical world. The other tradition, almost as misleading, is a certain conception of Science with a capital "S." Science is said to be "reductionist" and "materialist," and so construed there is no room for consciousness in Science. If it really exists, consciousness must really be something else. It must be reducible to something else, such as neuron firings, computer programs running in the brain, or dispositions to behavior. There are also a number of purely technical difficulties to neurobiological research. The brain is an extremely complicated mechanism with about a hundred billion neurons in ... (Rest nicht frei). " [https://www.nybooks.com/articles/2013/01/10/can-information-theory-explain-consciousness/].
Erwiderung von C. Koch u. G. Tononi in: The New York Review of Books, 07.03.2013 [https://www.nybooks.com/articles/2013/03/07/can-photodiode-be-conscious/?pagination=false&printpage=true] mit einer weiteren Erwiderung von J. Searle.

Field

Kognitionswissenschaft

LCSH

Consciousness
Mind and body
Free will and determinism
Life
Personal Autonomy
Existentialism

RSWK

Bewusstsein / Willensfreiheit / Leib-Seele-Problem / Neurowissenschaftler / Erlebnisbericht 1990-2010
Koch, Christof / Autobiographie 1990-2010
Koch, Christof *1956-* / Bewusstsein / Willensfreiheit / Leib-Seele-Problem / Neurowissenschaften / Autobiographie

BK

77.47 (Bewußtseinszustände)
08.32 (Erkenntnistheorie)

DDC

153 / dc23

GHBS

HRC (E)

LCC

B808.9

RVK

CC 5500
CZ 1000
WW 2200

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5. Koch, C.; Greenfield, S.: Wie geschieht Bewußtsein? (2008) 0.17

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