HC Hippocampus MDP n LGN Retina (A) Lateral (left) and mediai (right) view of the human brain. (B) Two similar views and (C) an unfolded and flattened map of the macaque's monkey brain. Ali non-white areas are involved with visual processing. The human and monkey brains are drawn at different scales.( D) Organizational chart of the monkey's visual system. Optical information flows from the retina in a quasi-hierarchical manner through a large numbcr of cortical areas. Most of the links are reciprocai. Only the retina. LGN,V I, and V2 are drawn with some of their substructures. (B)-(D) are modified from Van Essen and Gallant (1994) and Felleman and Van Essen (1991). Por more anatomical information, see http://brainmap.wustl.edu. The Quest for Consciousness A Neurobiologicàl Approach The Quest for Consciousness A Neurobiological Approach Christof Koch Roberts and Company Publishers Englewood, Colorado Roberts & Company Publishers 4660 South Yosemite Street RO.B ox 9154 Englewood, Colorado 80I li Intemet: www.roberts-pubIishers.com Telephone: (303)2 21-3325 Orderinginformation:( 800) 351-II6I Fax: (516)423-4097 Intemet: www.roberts-pubIishers.com Publisher: Ben Roberts Production Manager: Leslie Galen, Integre Technical Publishing Co., Ine. Manuscript Editor: John Murdzek Designer: Mark Ong, Side by Side Studios Compositor: Integre Technical Publishing Co., Ine. lUustrator: Emiko-Rose Paul, Echo Medicai Media Printer and Binder: Malloy Incorporated Copyright © 2004 by Roberts Se Company Publishers About the type: Minion is a 1990 Adobe Originals typeface by Robert Slimbach. Minion is inspired by classical, old-style typefaces of the late Renaissance, a period of elegant, beautiful, and highly readable type designs. Created primarily for text setting, Minion combines the aes- thetic and functional qualities that make text type highly readable with the versatility of digitai technology. About the paper: Finch Opaque is a smooth, bright stock with high opacity, making it readable and well suited for half-tones and illustrations. Reproduction or translation of any part of this work beyond that permitted by Section 107 or 108 of the 1976 United States Copyright Act without the permission of the copyright owner is unlawfùl. Requests for permission or further information should be addressed to the Permis- sions Department, Roberts 8c Company Publishers. Library of Congress Cataloging-ìn-Publication Data Koch, Christof. The quest for consciousness: a neurobiological approach / Christof Koch. p. cm. Includes bibliographical references and index. ISBN 0-9747077-0-8 (hardcover) 1. Consciousness-Physiological aspects. 2. Neurobiology-Research. I. Title. QP411.K63 2004 153-dc22 2003023807 Printed in the United States of America 10 987654321 I dedicate this hook to FRANCIS CRICK Friend, Mentor, and Sdentisi