Consciousness and the social brain michael s a graziano

A E= mc This eBook is downloaded from www.PlentyofeBooks.net ∑ PlentyofeBooks.net is a blog with an aim of helping people, especially students, who cannot afford to buy some costly books from the market For more Free eBooks and educational material visit www.PlentyofeBooks.net Uploaded By $am$exy98 theBooks CONSCIOUSNESS AND THE SOCIAL BRAIN SPECULATIVE EVOLUTIONARY TIMELINE OF CONSCIOUSNESS The theory at a glance: from selective signal enhancement to consciousness About half a billion years ago, nervous systems evolved an ability to enhance the most pressing of incoming signals Gradually, this attentional focus came under top-down control To effectively predict and deploy its own attentional focus, the brain needed a constantly updated simulation of attention This model of attention was schematic and lacking in detail Instead of attributing a complex neuronal machinery to the self, the model attributed to the self an experience of X—the property of being conscious of something Just as the brain could direct attention to external signals or to internal signals, that model of attention could attribute to the self a consciousness of external events or of internal event As that model increased in sophistication, it came to be used not only to guide one’s own attention, but for a variety of other purposes including understanding other beings Now, in humans, consciousness is a key part of what makes us socially capable In this theory, consciousness emerged first with a specific function related to the control of attention and continues to evolve and expand its cognitive role The theory explains why a brain attributes the property of consciousness to itself, and why we humans are so prone to attribute consciousness to the people and objects around us Timeline: Hydras evolve approximately 550 million years ago (MYA) with no selective signal enhancement; animals that show selective signal enhancement diverge from each other approximately 530 MYA; animals that show sophisticated top-down control of attention diverge from each other approximately 350 MYA; primates first appear approximately 65 MYA; hominids appear approximately MYA; Homo sapiens appear approximately 0.2 MYA Consciousness and the Social Brain Michael S A Graziano Oxford University Press is a department of the University of Oxford It furthers the University’s objective of excellence in research, scholarship, and education by publishing worldwide Oxford New York Auckland Cape Town Dar es Salaam Hong Kong Karachi Kuala Lumpur Madrid Melbourne Mexico City Nairobi New Delhi Shanghai Taipei Toronto With offices in Argentina Austria Brazil Chile Czech Republic France Greece Guatemala Hungary Italy Japan Poland Portugal Singapore South Korea Switzerland Thailand Turkey Ukraine Vietnam Oxford is a registered trademark of Oxford University Press in the UK and certain other countries Published in the United States of America by Oxford University Press 198 Madison Avenue, New York, NY 10016 © Oxford University Press 2013 All rights reserved No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, without the prior permission in writing of Oxford University Press, or as expressly permitted by law, by license, or under terms agreed with the appropriate reproduction rights organization Inquiries concerning reproduction outside the scope of the above should be sent to the Rights Department, Oxford University Press, at the address above You must not circulate this work in any other form and you must impose this same condition on any acquirer Library of Congress Cataloging-in-Publication Data Graziano, Michael S A., 1967– Consciousness and the social brain / Michael S.A Graziano pages cm Includes bibliographical references and index ISBN 978–0–19–992864–4 Consciousness Brain I Title BF311.G692 2013 153—dc23 2012048895 987654321 Printed in the United States of America on acid-free paper For Sabine Contents Acknowledgments PART ONE The Theory The Magic Trick Introducing the Theory Awareness as Information Being Aware versus Knowing that You Are Aware The Attention Schema Illusions and Myths Social Attention How Do I Distinguish My Awareness from Yours? Some Useful Complexities PART TWO Comparison to Previous Theories and Results 10 Social Theories of Consciousness 11 Consciousness as Integrated Information 12 Neural Correlates of Consciousness 13 Awareness and the Machinery for Social Perception 14 The Neglect Syndrome 15 Multiple Interlocking Functions of the Brain Area TPJ 16 Simulating Other Minds 17 Some Spiritual Matters 18 Explaining the Magic Trick NOTES INDEX Acknowledgments Many thanks to the people who patiently read through drafts and provided feedback Thanks in particular to Sabine Kastner, Joan Bossert, and Bruce Bridgeman At least some of the inspiration for the book came from Mark Ring, whose unpublished paper outlines the thesis that consciousness must be information or else we would be unable to report it Some of the material in this book is adapted from a previous article by Graziano and Kastner in 2011 CONSCIOUSNESS AND THE SOCIAL BRAIN PART ONE THE THEORY The Magic Trick I was in the audience watching a magic show Per protocol a lady was standing in a tall wooden box, her smiling head sticking out of the top, while the magician stabbed swords through the middle A man sitting next to me whispered to his son, “Jimmy, how you think they that?” The boy must have been about six or seven Refusing to be impressed, he hissed back, “It’s obvious, Dad.” “Really?” his father said “You figured it out? What’s the trick?” “The magician makes it happen that way,” the boy said The magician makes it happen That explanation, as charmingly vacuous as it sounds, could stand as a fair summary of almost every theory, religious or scientific, that has been put forward to explain human consciousness What is consciousness? What is the essence of awareness, the spark that makes us us? Something lovely apparently buried inside us is aware of ourselves and of our world Without that awareness, zombie-like, we would presumably have no basis for curiosity, no realization that there is a world about which to be curious, no impetus to seek insight, whether emotional, artistic, religious, or scientific Consciousness is the window through which we understand The human brain contains about one hundred billion interacting neurons Neuroscientists know, at least in general, how that network of neurons can compute information But how does a brain become aware of information? What is sentience itself? In this book I propose a novel scientific theory of what consciousness might be and how a brain might construct it In this first chapter I briefly sketch the history of ideas on the brain basis of consciousness and how the new proposal might fit into the larger context The first known scientific account relating consciousness to the brain dates back to Hippocrates in the fifth century B.C.1 At that time, there was no formal science as it is recognized today Hippocrates was nonetheless an acute medical observer and noticed that people with brain damage tended to lose their mental abilities He realized that mind is something created by the brain and that it dies piece by piece as the brain dies A passage attributed to him summarizes his view elegantly: Men ought to know that from the brain, and from the brain only, arise our pleasures, joys, laughter and jests, as well as our sorrows, pains, griefs and tears Through it, in particular, we think, see, hear, and distinguish the ugly from the beautiful, the bad from the good, the pleasant from the unpleasant The importance of Hippocrates’s insight that the brain is the source of the mind cannot be overstated It launched two and a half thousand years of neuroscience As a specific explanation of consciousness, however, one has to admit that the Hippocratic account is not very helpful Rather than explain consciousness, the account merely points to a magician The brain makes it happen How the brain does it, and what exactly consciousness may be, Hippocrates left unaddressed Such questions went beyond the scope of his medical observations Two thousand years after Hippocrates, in 1641, Descartes2 proposed a second influential view of the brain basis of consciousness In Descartes’s view, the mind was made out of an ethereal substance, a fluid, that was stored in a receptacle in the brain He called the fluid res cogitans Mental substance When he dissected the brain looking for the receptacle of the soul, he noticed that almost every brain structure came in pairs, one on each side In his view, the human soul was a single, unified entity, and therefore it could not possibly be divided up and stored in two places In the end he found a small single lump at the center of the brain, the pineal body, and deduced that it must be the house of the soul The pineal body is now known to be a gland that produces melatonin and has nothing whatsoever to with a soul Descartes’ idea, though refreshingly clever for the time, and though influential in philosophy and theology, did not advance the scientific understanding of consciousness Instead of proposing an explanation of consciousness, he attributed consciousness to a magic fluid By what mechanism a fluid substance can cause the experience of consciousness, or where the fluid itself comes from, Descartes left unexplained—truly a case of pointing to a magician instead of explaining the trick One of the foundation bricks of modern science, especially modern psychology, is a brilliant treatise so hefty that it is literally rather brick-like, Kant’s A Critique of Pure Reason, published in 1781.3 In Kant’s account, the mind relies on what he termed “a priori forms,” abilities and ideas within us that are present first before all explanations and from which everything else follows On the subject of consciousness, therefore, Kant had a clear answer: there is no explaining the magic It is simply supplied to us by divine act Quite literally, the magician did it Hippocrates, Descartes, and Kant represent only three particularly prominent accounts of the mind from the history of science I could go on describing one famous account after the next and yet get no closer to insight Even if we fastforward to modern neuroscience and examine the many proposed theories of consciousness, almost all of them suffer from the same limitation They are not truly explanatory theories They point to a magician but not explain the magic One of the first, groundbreaking neurobiological theories of consciousness was proposed in 1990 by the scientists Francis Crick (the co-discoverer of the structure of DNA) and Christof Koch.4 They suggested that when the electrical signals in the brain oscillate they cause consciousness The idea, which I will discuss in greater detail later in the book, goes something like this: the brain is composed of neurons that pass information among each other Information is more efficiently linked from Huxley, L., hyperactive agency detection device (HADD), 212–13 individual labeling, 189–90, 192–93 information See also awareness, as information about others, 192 about the self, 100 in chunks, 109–10, 112, 115 consciousness as, 80, 225 descriptive information, 34, 70, 124, 137 highly integrated information, 147 model of attention, 164, 195 nonverbal information, 43 processing in brain, 22, 39–40 sensory information, 63, 78, 102, 133–34 social perception and awareness, 192 somatosensory information/processing, 78, 151 sound information, 70, 125 visual information, 34–35, 39 integrated information approach, to consciousness not always conscious, 140–45 overview, 137–38 reportability of consciousness, 146–49 testing difficulties, 145–46 theories of, 138–40 intentionality in action, 162, 181 brain and, 89, 192 in consciousness, 122–23, 201, 204, 225–26 neurons and, 191 internal model of attention, 68 interpreter mechanism in brain, 121–22, 124 introspection attention schema theory, 52, 116 in awareness, 43–45, 113 brain and, 15–16, 28, 70, 102, 147 in consciousness, 35, 80–81, 152, 164–65 intuition and, 131, 195 intuition attention schema theory, 205 awareness and, 49, 69, 131 consciousness and, 81 conventional intuition, 201–2 introspection and, 131, 195 mesmerism, 75–76 self-familiarity in, 132 items I through IV, in brain processing, 54, 56 joyfulness feelings, 104 Kant, Immanuel, 5, 40, 229 Kanwisher, N., 161 Kastner, Sabine, Kingstone, A., 89 the knower and the known, 129–31 knowledge of awareness, 53–57 consciousness and, 14, 135 explicit knowledge, 25, 51 self-knowledge, 14, 29, 129, 135 Koch, Christof, 5, 139, 144 Koenig, H G., 212 level of certainty, 15–16 Liberman, A M., 1187 Libet, B., 122 Linnaeus, C., loss of awareness, 12, 129, 168, 171–72, 176 macaque monkeys, brain studies, 186–87 magnetic resonance imaging (MRI), 123 magnetic theory of consciousness, 119 medial prefrontal cortex (MPFC), 163–65, 190 melatonin production, memory autobiographical memory, 29, 110, 113, 179–83 consciousness and, 14 neglect syndrome and, 168 recalled memories, 26, 88, 110, 113 mental attributes of awareness (MA), 114 mental self, 110, 112–13 mental state in attention schema, 96 Mesmer, Anton, 75 mesmerism, 75–76 metacognition theory of consciousness, 53 metacosmic theory of consciousness, 119 mirror neuron theory circularity, 190 difficulties with, 188–90 expert theory and, 190–94 individual labeling, 189–90 overview, 186–88 model constructs by brain, 83–84 model of attention attention schema and, 31f, 37, 59–60, 115, 208 awareness as, 27, 83, 86f, 88, 92, 165, 208 brain and, 174 complex, 219 descriptive, 125–26, 182 informational, 164, 195 internal, 68 overview, 25 predictive, 67, 210–11 model of awareness in brain, 124, 204, 208 intuition and, 72–73 perceptual nature of, 85, 87, 102 physical embodiment in, 114 monkey brain, 160–61, 160f movement control in body schema, 66–67 Muller-Lyer illusion, 84, 84f multiple personalities, 105–7 muscle control, 141 mystical theory of consciousness, 119 narrative See self-narrative natural selection theory, 7–8 neglect syndrome brain areas associated with, 169–71, 181 loss of awareness and, 171–72 as one-sided, 174–76 overview, 167–68 social perception disability, 173 neural correlates, of consciousness attention schema and, 164–66 binocular rivalry, 153–54, 156–57 blindsight, 155–56 overview, 151–53 neuronal theory of consciousness, 119 neurons awareness and, 19, 180 biological motion neurons, 193–94 consciousness and, 3–6 decision-making process and, 44–46 mirror neurons, 186–88 monitoring activity of, 39 oscillations of, rubber hand illusion, 65 synchronization of, 138–39 neuroscience brain studies and, 69, 197–98 of consciousness, social neuroscience, 159–62 visual attention and, 85–88, 86f Newton, Isaac, 47, 49, 80 Newtonian determinism, 200 Nisbett, R E., 122 nonhuman animals and consciousness, 214–16 nonverbal information, 43 object of awareness, 111 open-loop awareness, 203 The Origin of Species (Darwin), oscillation of neurons, 138–39 out-of-body illusion, 70–72, 180–81 parietal lobe clinical neglect and, 169–70, 173 hand–eye coordination, 141 interlocking functions of, 182 mirror-neuron network, 187 posterior parietal lobe, 141, 169 ventral attention system, 178 parieto-frontal attention network, 178 Perrett, D I., 88 personal consciousness, 132–34 personal perspective, 101–2 phenomenal consciousness, 55 philosophical theory of consciousness, 119 physical embodiment (PA), 114 physical process modeling, 28 physical properties and awareness, 79–81 physical self (PS), 29, 63, 110, 113–14 physical stimulus, 50, 67, 79 physiological attention, 50–52 Piaget, J., 74 pineal body, 5, 164 Pinocchio illusion, 63–65 Posner, M I., 89–91, 90f posterior parietal lobe, 141, 169 predictive model of attention, 67, 210–11 primary visual cortex, 155–57 private awareness group consciousness, 103–5 information about the self, 100 multiple personalities, 105–7 overview, 99 personal perspective, 101–2 resonance, 103 somatosensory processing, 100 of someone else’s awareness, 100–101 property of awareness, 73, 87, 221 psychokinesis myth, 76–77 psychological theory of consciousness, 119 Purves, Dale, 208 quantum mechanics, 119, 200 recalled memories (RS), 26, 88, 110, 113 receptacle of the soul, 4–5 religious theory of consciousness, 119 reportability of consciousness, 146–49 representation of decisions, 46–49 resonance loop, 103, 194–95 Rizzolatti, G., 186 robotics and attention schema, 68 Royal Society of London, 47 rubber hand illusion, 65 schema, defined, 25–26 schizoid personality disorder, 128 Searle, J R., 56 selective signal enhancement, ii self-attention, 125 self-awareness absence of, 114 awareness vs., 125–26, 135 consciousness in, 165 property of, 101 spirituality of, 197 self-knowledge and consciousness, 14, 29, 129, 135 self-narrative, 120–25, 130 Selfridge, O G., 25 self-understanding, 14, 109, 132 sensory illusion, 205–6 sensory information, 63, 78, 102, 133–34 shared-consciousness, 104–5 Shelly, Mary, 75 Shiavo, Terri, 204–5 simulation theory expert theory, 190–94 individual labeling, 192–93 mirror neurons, 186–90 overview, 185–86 resonance loop, 194–95 social anxiety disorder, 128 social attention eye tracker studies, 88–94, 90f overview, 83–85, 84f perception of awareness in others, 85–88, 86f probing for attention schema, 94–97, 95f temporo-parietal junction and, 178–79 social cognition, 83–84, 162–63 social cohesion, 210–11 social intelligence and consciousness, 119 social narrative, 120 social neuroscience, 159–62, 160f, 161f social perception and awareness facial expressions and, 72, 83, 162 information and, 192 neglect syndrome and, 173 overview, 11, 30–35, 31f, 32f, 159 simulation theory and, 185 social cognition and, 83, 162–63 social neuroscience, 159–62, 160f, 161f social theories of consciousness in absence of other people, 126–27 advantage of, 146–47 attention schema theory as, 124–25, 128–29 autism and, 127–29 improving on, 134–36 the knower and the known, 129–31 overview, 119–20 personal consciousness, 132–34 reportability of, 146–49 self-awareness and, 125–26 self-narrative, 120–25 social user interface (SUI), 219 sociopathic personality type, 128 somatosensory information/processing, 78, 100, 151 someone else’s awareness, 100–101 Sosis, R., 198 the soul coma patients and, 204 in computers, 222 in fictional characters, 210 location of, 164, 198 receptacle of, 4–5 substance of, 79 theories of, 12 sound information, 70, 125 spatial attention, 89, 182 speech ability, 19, 41 spirituality, and consciousness See also God; the soul after brain death, 220–24 atheism, 197, 199, 212, 221, 226–27 awareness and evolution, 208–14 in computers, 216–20 consciousness A and B, 202–8 deities, belief in, 7, 199, 212, 224–25 devils, belief in, 12, 212 existence of God, 224–27 free will, 200–202 in nonhuman animals, 214–16 overview, 197–200 ventriloquism, 205–7 split-brained subjects, 121 squirrel-in-head analogy, 15–18 stroke patients, 169 subjective awareness, 43, 52 superior temporal polysensory area (STP), 160–61 superior temporal sulcus (STS) attention schema, 161–64, 161f, 166 biological motion neurons, 193–94 brain damage and, 170, 173 computation, 186 defined, 11–12, 33 eye tracking and, 88 interlocking functions, 181–83 overview, 177–78 social cognition and, 190 social intelligence and, 32f superstitions, 80, 212–13 synchronization of neurons, 138–39 temporo-parietal junction (TPJ) attention schema, 163, 164, 166 autobiographical memory and, 179–80, 183 brain damage and, 169–71, 173 computation, 186 defined, 12, 33 interlocking functions, 181–83 out-of-body experience, 180–81 overview, 177–78 social cognition and, 190 ventral attention system, 178–79 theories of consciousness, 8, 12, 19, 107, 119 theory of mind mechanism of, 89 in nonhuman animals, 215 social perception and, 86, 162–63 thinking modes, 113 Titchner, E B., 72 Tononi, G., 139–40, 144 top-down signal in brain, 23, 24f, 61 Turing, A M (Turing test), 217 unconscious processes in actions, 201 in brain, 37, 122 information needs of, 146 zombie units, 142 unified awareness, 29–30 unified consciousness, 152 ventral attention system, 178–79 ventriloquism, 84–85, 205–7 verbalizable propositions, 55 visual attention/awareness neuronal substrate of, 151 neuroscientific account of, 85–88, 86f overview, 60, 61–62 personal perspective and, 101–2 visual cortex and, 156–57 visual-consciousness network, 154 visual cortex, 155–57 visual illusions, 50 visual information, 34–35, 39 visual stimuli awareness and, 29, 31 brain and, 24f, 46–47, 55–56, 107 brain processing of, 54, 69, 155 integrated information and, 143–44 monkey brain, 160–61, 160f presence of, 44 Watson computer, 142, 219 white light, perception, 47–48, 50 whiteness, experience of, 139–40 Wilson, T D., 122 Winer, G A., 74 zombie units in brain, 142 Thank You Want More Books? We hope you learned what you expected to learn from this eBook Find more such useful books on www.PlentyofeBooks.net Learn more and make your parents proud :) Regards www.PlentyofeBooks.net ... define consciousness and awareness Consciousness is inclusive, and awareness is a specific act applied to the information that is in consciousness Figure 2.1 diagrams the proposed relationship... awareness: we can at least sometimes say that we have it Most theories of consciousness are magical in two ways First, Arrow A is magical How awareness emerges from the brain is unexplained Second,... machinery scans and summarizes internal data, it has no direct access to the process of attention itself Instead, it has access to the data in the attention schema It can access, summarize, and