THE FEELING OF WHAT HAPPENS

Body and Emotion in the Making of Consciousness
By Antonio R. Damasio.
Harcourt Brace.

A neurologist explores the reasons that consciousness feels, well, conscious.
By WILLIAM H. CALVIN

Editors' Choice: "Consciousness is the great unsolved problem in neuroscience. Antonio R. Damasio, a neurologist who is a gifted writer, derives his theory of it from experiences of patients over a generation. The reader comes to understand the difference between intelligence and consciousness and to experience how emotions and feelings play a central role in consciousness. Consciousness is seen as an internal narrative whose images supply comment on the objects of our thoughts. No external spirit is needed to explain it. And ''you as a self'' are not telling the story since the ''core you'' is born only when primordial stories are being told in your mind; borrowing a line from T. S. Eliot, Damasio says, ''You are the music while the music lasts.'' In extended consciousness -- which gives rise to creativity, conscience and identity -- the here and now of core consciousness are present, but flanked by the past, which illuminates them, and by the anticipated future. The drama of life, he thinks, comes solely from consciousness, and that lets us make life better. But it comes at a price -- the risk of danger and of knowing when pleasure is gone. This is not casual reading, but eventually anyone can master it; and unlike any other book here, it will change your experience of yourself.

his decade has seen a number of books tackling consciousness from various angles, ranging from Daniel Dennett's ''Consciousness Explained,'' a top-down demolition of the little person inside, to my bottom-up attempt in ''The Cerebral Code'' at a contemplative neural circuitry using Darwinian processes.

Until now, none have really approached consciousness from the standpoint of why it feels the way it does -- a livelier question to the nonexpert. I formerly dismissed such ''qualia'' issues as subject-object confusions engendered by our language habits, but Antonio R. Damasio (the Portuguese-educated Iowa neurologist, known to half a million readers as the author of ''Descartes' Error'') has now persuaded me to pay attention -- and in a way that few philosophers could have done, by citing many neurology patients with odd limitations, ones that show useful distinctions.

It's not the sort of humanistic detective book that Oliver Sacks writes. Damasio tries to piece together a big story, one that philosophers have long struggled with. He has one of the best brain stories of the decade and, fortunately, he writes well, his patients come alive on the page and his theory makes a lot of sense -- though I suspect he occasionally makes a distinction without a difference when he talks of ''knowing.'' This is a must-read book for anyone wanting a neurologist's perspective on one of the greatest unsolved mysteries, human consciousness and how it exceeds that of the other apes.

Neurologists usually confine themselves to the simplest aspects of consciousness, the spectrum from coma to stupor to wakefulness to fully oriented in time and place. This can be studied in most animals fancier than jellyfish; some of us say that calling this ''consciousness'' confuses the light switch with the light. Neuroscientists occasionally venture into the other approachable aspect, selective attention -- for which fish might suffice as subjects. Damasio puts such foundational aspects in their place and builds on them, all the way up to the autobiographical self and its relation to consciousness, even considering (all too briefly) creativity and conscience. Whatever your favorite connotation of the C word, it is likely ''The Feeling of What Happens'' covers that base, a rare accomplishment among consciousness books.

But Damasio's really impressive feat is that he integrates all this with emotions and feelings, making them play a central role in the experience of consciousness. He doesn't confine himself to the emotions that an observer could detect but addresses the feelings that only exist internally. The title of this book is meant to be taken literally.

It begins, in a tradition that goes back at least to the Book of Genesis, with a bang-up first chapter that signposts the rest of the book, followed by a less poetic alternative, and both are excellent. Thereafter the terminology of neuroanatomy and neurology creeps in (readers might start with a useful tutorial, called ''Notes on Mind and Brain,'' at the back of the book). Damasio's genesis of consciousness even has the biblical ''begats'': ''The nonconscious neural signaling of an individual organism begets the proto-self which permits core self and core consciousness, which allow for an autobiographical self, which permits extended consciousness. At the end of the chain, extended consciousness permits conscience.''

Consciousness is more than being awake, as one of Damasio's epileptic patients, suffering an absence-of-consciousness seizure, illustrates: ''Were you to have interrupted the patient at any point during the episode, he . . . would not have known who you were. . . . He would not know who he was or what he was doing.'' He might take a drink or open a door, but ''there would have been no plan, no forethought, no sense of . . . wishing, wanting, considering, believing. There would have been no sense of self, no identifiable person with a past and an anticipated future. . . . In other words, the patient would have had some elementary aspects of mind . . . but he would not have had a normal consciousness.'' Then comes Damasio's succinct summary of the mental process that consciousness entails: ''He would not have developed . . . an image of knowing centered on a self; an enhanced image of the objects he was interacting with; a sense of the appropriate connection to what went on before each given instant or what might happen in the instant ahead.''

One technological metaphor neuroscientists use for the enhancement of some images over others, so essential to our sense of self, is a black-and-white movie scene in which one actor becomes colorized, gradually standing out, until another actor develops color and the first fades back to gray scale. Damasio has a symphonic notion of how higher-order brain maps interact to achieve such shifting emphasis that is far more sophisticated. Happily, his ''orchestra'' doesn't really require a conductor any more than a string quartet does. We do, nonetheless, have the illusion of a little conductor inside, and Damasio suggests how it might arise: ''The images in the consciousness narrative flow like shadows along with the images of the object for which they are providing an unwitting, unsolicited comment. To come back to the metaphor of movie-in-the-brain, they are within the movie. There is no external spectator.'' And later, alluding to a line by T. S. Eliot: ''The story . . . is not told by some clever homunculus. Nor is the story really told by you as a self because the core you is only born as the story is told, within the story itself. You exist as a mental being when primordial stories are being told, and only then; as long as primordial stories are being told, and only then. You are the music while the music lasts.''

Core consciousness is closely related to such prominent background feelings as excitement, fatigue/energy, wellness/sickness, tension/relaxation, surging/dragging, balance/imbalance and harmony/discord. If this core is the indispensable foundation of consciousness for Damasio, extended consciousness is its glory. ''When we think of the greatness of consciousness we have extended consciousness in mind.'' And that ''goes beyond the here and now of core consciousness, both backward and forward. The here and now is still there, but it is flanked by the past, as much past as you may need to illuminate the now effectively, and, just as importantly, it is flanked by the anticipated future.''

Extended consciousness is not the same as intelligence: ''Extended consciousness has to do with making the organism aware of the largest possible compass of knowledge, while intelligence pertains to the ability to manipulate knowledge so successfully that novel responses can be planned and delivered.'' However, Damasio generally chooses not to complicate his analysis with all that language adds. He gives little elaboration about how consciousness is expanded by structured thought processes, best seen in language, with syntax, alternative agendas, games with arbitrary rules, chains of logic -- and in our fascination with discovering hidden patterns, whether in music or puzzles or punch lines. Most of what Damasio treats would apply equally well, in my opinion, to the less structured consciousness of chimpanzees and bonobos.

Damasio's ''autobiographical self'' is always under reconstruction: ''When we discover what we are made of and how we are put together, we discover a ceaseless process of building up and tearing down, and we realize that life is at the mercy of that never-ending process. . . . It is astonishing that we have a sense of self at all, that we have . . . some continuity of structure and function that constitutes identity, some stable traits of behavior we call a personality.'' Because this easily tipped balance between creation and destruction is likely to underlie our mental life and memories, I am skeptical of proposals to resurrect conscious persons in silicon after death -- even though, as Damasio notes, it ought to be possible, building from scratch, to achieve some form of machine ''consciousness.''

And speaking of a mind without a body, there is a memorable discussion of locked-in syndrome, where consciousness is preserved in spite of total paralysis. It has some speed bumps for the neuroanatomy-challenged, but no one should skim the wrap-up chapters. ''The drama of the human condition comes solely from consciousness,'' Damasio says, and that allows us to create a better life, even though the price is high -- not just the price of risk and danger and pain. It is the price of knowing risk, danger and pain . . . the price of knowing what pleasure is and knowing when it is missing or unattainable.''

William H. Calvin is a neuroscientist at the University of Washington and the author, with Derek Bickerton, of the forthcoming ''Lingua ex Machina: Reconciling Darwin and Chomsky With the Human Brain.''