Текст книги "The Turing Option"

Автор книги: Harry Harrison

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“Erin Snaresbrook,” she said as they shook hands. “We haven’t met before – but I’ve heard about you. Alfred J. Benicoff. You’re the one who beat down the opposition to the use of human embryonic tissue grafts. That’s one of the things that made my work here possible.”

“Thank you – but that was a long time ago. I’m in government now, which means that I spend most of my time looking at other people’s research.”

“A waste of talent.”

“Would you prefer a lawyer in the job?”

“God forbid. Your point taken. Now let me tell you about Brian. I have very little time. His skull is open and he is on life support. I’m waiting for the next V.I. records.”

“V.I.?”

“Volume Investigation. Infinitely better than looking at X rays or any other single type of image. It combines the results of every available type of scan – including the old tomograms and NMRs as well as the latest octopolar antibody fluorescence images. These are all churned up together in an ICAR-5367 spatial signal processing computer. This can display not only images from the patient’s data, but can also highlight or exaggerate the differences between that patient and the typical person, or changes since earlier scans of the same patient. So when the new V.I. data is ready I will have to go. Up until now it has been emergency procedures just to save Brian’s life. First total body hypothermia, then brain cooling to slow oxygen intake and all the other metabolic processes. I used anti-hemorrhage drugs, mainly RSCH, as well as anti-inflammatory hormones. With the first surgery I cleaned the wound and removed necrotic tissue and bone fragments. In order to restore the anatomy of the ventricles I was forced to sever part of the corpus callosum.”

“Isn’t that part of the connection between the two halves of the brain?”

“It is – and it was a serious, and possibly dangerous, decision. But I had no choice. So at this time the patient is really two half-brained individuals. Were he conscious this would be a disaster. But, having severed the corpus callosum cleanly, I hope to be able to reconnect the two halves completely. Tell me – what do you know about the human brain?”

“Very little – and all probably out of date since my undergraduate days.”

“Then you are completely out of date. We are at the threshold of a new era, when we will be able to call ourselves mind surgeons as well as brain surgeons. Mind is the function of the brain and we are discovering how it operates.”

“Specifically, then, in Brian’s case, how serious is the damage – and is it repairable?”

“Look here, at these earlier V.I. images, and you will see.” She pointed to the colored holograms that apparently floated in midair. The three-dimensional effect was startling – as though he was looking inside the skull itself. Snaresbrook touched a white patch, then another. “This is where the bullet went into the skull. It exited here, on the right. It passed through the cortex of the brain from side to side. The good news is that the cerebral cortex of the brain seems mostly intact, as are the central organs of the middle brain. The amygdala here appears to be undamaged, as well as most important of all, the hippocampus, this roughly seahorse-shaped organ. This is one of the most critical agencies involved in forming memories, and retrieving them. It is the powerhouse of the mind – and it wasn’t touched.”

“That’s the good news. And the bad—”

“There is some cortical damage, though not enough to be very grave. But the bullet severed a large number of bundles of nerve fibers, the white matter that makes up the largest portion of the brain. These serve to interconnect different parts of the cortex to one another – and also to connect them to other midbrain organs. This means that parts of Brian’s brain are disconnected from the data bases and other resources that they need for performing their functions. Therefore at this moment Brian has no memories at all.”

“You mean his memory is gone, destroyed?”

“No, not exactly. Look – the largest parts of his neocortex are still intact. But most of their connections are broken – see here, and here. To the rest of the brain they do not exist. The structures, the nerve connections that constitute his memories are still there – in various sections of his shattered brain. But they can’t be reached by the other parts, so they are meaningless by themselves. Like a box full of memory disks without a computer. This is a disaster since we are our memories. Now Brian is essentially mindless.”

“Then he is a… vegetable.”

“Yes – in the sense that he cannot think. You might say mat his memories have been largely disconnected from his brain computers, so that they cannot be retrieved or used. He cannot recognize things or words, faces, friends, anything. In short, so far as I can see, he no longer can think to any degree. Consider this. Other than size, one could say that there is little observable difference between most of the brain of a man and a mouse – except for those magnificent structures of our higher brain – the neocortex that evolved in the ancestors of the primates. In this present state, poor Brian, my friend and my collaborator, is little more than a selfless shell, a submammalian animal.”

“Is that it? The end?”

“No, not necessarily. Although Brian cannot actually think, he is definitely not brain-dead as the lawyers put it. A few years ago nothing more could have been done. This is no longer true. I am sure that you know that Brian has helped me in a practical application of his AI theories, the development of an experimental technique to rebuild severed brain connections. I have had a measure of success, but only on animals so far.”

“If there is a chance, any chance at all, you must take it. Can you do it, can you save Brian?”

“It is too early to say anything with any degree of certainty. The damage is extensive and I don’t know how much I can repair. The trouble is that in addition to the general trauma the bullet has severed millions of nerve fibers. It will be impossible for me to match up all of them. But I hope to identify a few hundred thousand and join them.’’

Benicoff shook his head. “You just lost me, doctor. You are going into his open skull and identify something like a million different and severed nerve fibers? That will take years.”

“It would if I had to do them one by one. However, computer-controlled microsurgical technology can now operate on many sites at one time. Our parallel computer can identify several connections every second – and there are 86,400 seconds in each day. If everything goes as planned the memory-probe process should only take a few days to identify and label the nerve fibers we must reconnect.”

“Can this be done?”

“Not easily. When a nerve fiber is cut off from its mother cell it dies. It is fortunate that the empty tube of the dead cell remains in place and this makes regrowth of the nerve possible. I will be using implants of my own design that will control that regrowth.” Snaresbrook sighed. “And after that, well, I fear that the nerve repair will just be the beginning. It is not simply a matter of connecting up all the severed nerves we can see.”

“Why is that not enough?”

“Because we must restore the original connections. And the problem is that all nerve fibers look, and are, almost the same. Indistinguishable. But we have to match them up correctly to get the right connections inside the mind. Memory, you see, is neither in the brain cells nor in the nerve fibers. It is mostly in the layout of the connections between them. To get things right, we shall need a third stage – after we’ve finished the second stage today. After that, we shall have to find a way to access and examine his levels of memory – and rearrange the new connections accordingly. This has never been done before and I am not sure that I can do it now. Ah, here we are.”

The technician hurried in with the multiscan cassette of the V.I. and inserted it into the projector; the three-dimensional hologram sprang into existence. Snaresbrook examined it closely, nodded grimly. “Now that I can see the extent of the damage, I can finish the debridement and prepare for the second and vital stage of this operation – the reconnection.”

“Just what is it you plan to do?”

“I’m going to use some new techniques. I hope to be able to identify the role that each of his nerve fibers once played in his various mental activities – by finding out where each of them fit into his semantic neural networks. These are the webs of brain connections that make up our knowledge and mental processes. I must also take the radical step of severing the remaining portions of his corpus callosum. This will provide the unique opportunity of making connections to virtually every part of his cerebral cortex. This will be dangerous – but will provide the best chance to reconnect the two halves completely.”

“I must know more about this,” Benicoff said. “Is there any chance you will let me observe the operation?”

“Every chance in the world – I have had up to five residents in the O.R. breathing down my neck at one time. It’s fine with me as long as you stay out of my way. What’s this sudden interest?”

“More than morbid curiosity, I assure you. You’ve described the machines you use and what they do. I want to see them in operation. I need to know more about them if I am going to ever know anything about AI.”

“Understood. Come along, then.”

3
February 10, 202

Benicoff, gowned and masked, stretchable boots pulled over his shoes, pressed his back to the green tiles of the wall of the operating room and tried to make himself invisible. There were two large lights on ceiling tracks that one of the nurses moved about and focused until the resident surgeon approved their positioning. On the table sterile blue sheets had been draped tentlike over Brian’s still figure. Only his head was exposed, projecting beyond the end of the table and held immovably by the pointed steel spokes of the head holder. There were three of them, screwed through the skin of his scalp and anchored firmly in the bone below. The bandages that covered the two bullet wounds were stark white in contrast to his orange skull, shaved smooth and painted with disinfectant.

Snaresbrook looked relaxed, efficient. Discussing the approaching operation with the anesthesiologist and the nurses, then supervising the careful placement of the projector. “Here is where I am going to work,” she said, tapping the hologram screen. “And this is where you are going to cut.”

She touched the outlined area that she had hiked onto the plate, checking once again that the opening would be large enough to reveal the entire area of injury, large enough for her to work within. Nodding with satisfaction, she projected the holograph onto Brian’s skull and watched while the resident painted the lines on the skin, following those of the image, matching it exactly. When he was finished more drapes were attached to the surrounding skin until only the area of the operation remained. Snaresbrook went out to scrub: the resident began the hour-long procedure to open the skull.

Luckily Benicoff had seen enough other surgical procedures not to be put off. He was still amazed at all the force that is needed to penetrate the tough skin, muscle and bone that armor the brain. First a scalpel was used to cut through to the bone; the scalp, spreading apart as it was severed, was then sewn to the surrounding cloth. After the bleeding arteries were sealed shut with an electric cautery it was time to penetrate the bone.

The resident drilled holes by hand, with a polished metal brace and bit. Bits of skull, like wood shavings, were cleared away by the nurse. It was hard work and the surgeon was sweating, had to lean back so that the perspiration could be dabbed from his forehead. Once the holes were through the bone he enlarged them with a different tool. The final step was to use the motorized craniotome, fitted with a bone-cutting extension, to connect the holes. After this had been done he worked the flat metal flap elevator between skull and brain to slowly pry up and free the piece of skull; a nurse wrapped the piece of bone in cloth and put it into an antibiotic solution.

Now Snaresbrook could begin. She entered the O.R., her scrubbed-clean hands held up at eye level, poked her arms through the sleeves of the sterile gown, slipped on the rubber gloves. The instrument table was rolled into position, the tools on it carefully laid out by the scrub nurse. The scalpels, retractors, needles, nerve hook, dozens of scissors and tweezers, all the battery of equipment needed for the penetration of the brain itself.

“Dural scissors,” Snaresbrook said, holding out her hand, then bent to cut open the outer covering of the brain. Once it had been exposed to the air, automatic sprays kept it moist.

Benicoff, standing against the wall, could not see the details now; was just as glad. It was the final stage that mattered, when they rolled over the odd-looking machine that was now pushed back against the wall. A metal box, with a screen, controls and a keyboard, as well as two shining arms that rose from the top. These ended in multibranching fingers that grew smaller and smaller in diameter, each tipped with a glistening fuzziness. This was caused by the fact that the sixteen thousand microscopic fingertips at the branching ends of the instrument were actually too small to be seen by the human eye. The multibranching manipulator had been developing for only a decade. Unpowered now, the fingers hung in limp bundles like a metallic weeping willow.

It took the surgeon two hours, working with the large microscope, scalpels and cautery, to clean the track of destruction, a slow and precise debridement of the lesion left by the bullet.

“Now we repair,” she said, straightening up and pointing to the manipulator. Like everything else in the O.R. it was on wheels; it was pushed into position. When it was switched on, the fingers stirred and rose, descended again under her control into the brain of its designer.

Snaresbrook’s skin was gray and there were black smears of fatigue under her eyes. She sipped her coffee and sighed.

“I admire your stamina, Doctor,” Benicoff said. “My feet hurt just from standing there and watching. Do all brain operations last that long?”

“Most of them. But this one was particularly difficult because I had to insert and fix those microchips into place. It was like combining surgery with solving a jigsaw puzzle, since every one of those PNEPs had a different shape in order to perfectly contact the surface of brain.”

“I saw that. What do they do?”

“They are PNEP film chips – programmable neural electron pathway devices. I have applied them to every injured surface of his brain. They will make connections to the cutoff nerve fibers that end at those surfaces, that control the regrowth of Brian’s nerves. They have been under development for years and have been thoroughly tested in animals. These chips have also been wonderfully effective in repairing human spinal injuries. But until now they have never been used inside human brains, except in a few small experiments. I would certainly not be using them if there were any good alternative.”

“What will happen next?”

“The chips are coated with living embryonic human nerve cells. What they should do is grow and provide physical connections from the end of each of the severed nerves to at least one of the quantum transistor gates on the surface of the PNEP. That process of growth should already have started, and will continue for the next few days.”

“As soon as those new nerve fibers grow in, I’ll start to program the PNEP chips. Each chip has enough switching capacity to take every nerve signal that comes in from any part of the brain and route it out along an appropriate nerve fiber that goes to another location in the brain.”

“But how could you know exactly where to send it?”

“That is precisely the problem. We will be dealing with several hundred million different nerves – and we don’t know now where any of them should go. The first stage will be to follow Brian’s brain’s anatomy. This should give us a crudely approximate map of where most of those fibers should go. Not enough to support fine-grained thought but enough, I hope, to restore a minimal level of functional recovery, despite all the errors in wiring. For example, if the motor area of his brain sends a signal to move, then some muscle should move, if not the right one. So we’ll have a response that later could be relearned or retrained. I have implanted a connector in Brian’s skin, just about here.” Erin touched the back of her neck just above her collar. “The computer communicates by inserting the microscopic ends of fiber-optic cables that communicate with each of the PNEP chips inside. Then we can use the external computer to do the search – to find opposite areas relating to the same memories or concepts. Once these are found, the computer can send signals to establish electronic pathways inside, between the appropriate PNEPs. Each separate chip is like an old-fashioned telephone exchange where one phone was plugged through a board to another phone. I’ll start using the neural telephone exchange inside Brian’s brain to reestablish the severed connections.”

Ben took a deep breath. “That’s it, then. You’ll restore all of his memory!”

“Hardly. There will be memories, skills and abilities that will be lost forever. Really all I hope to do is restore enough so Brian may be able to relearn what is now gone. An incredible amount of work is needed. To understand the complexity of the brain, you must realize that there are many times more genes involved in growing the structure of the brain than in any other organ.”

“I appreciate that. Do you believe that the personality, the person we know as Brian, is still alive?”

“I believe so. During the operation I saw his limbs move through the drapes, a familiar movement that reminded me of the way we move when we are dreaming. A dream! What could that half-ruined brain possibly dream about?’’

Darkness…

Timeless darkness, warm darkness.

Sensation. Memory.

Memory. Awareness. Presence. Around and around and around. Going nowhere, relating to nothing else, an endless loop.

Darkness. Where? The closet. Safety was in the darkness of the closet. Refuge of a child. No light. Just sound. The memory repeated itself, over and over.

Sound? Voices. Voices he knew. Voices he hated. And a new one. A strange one. An accent like on telly. Not Irish. American, he recognized that. Americans, they came to the village. To the pub. Took pictures. One took a picture of him. Gave him a golden twenty pence. Spent it on sweets. Ate them all. Americans.

Here? In this house. Curiosity took his hand to the knob on the closet door. He held it, turned it and opened it slowly. The voices were louder now, clear. Shouting even, that would be his uncle Seamus.

“A bloody sodding nerve to come here! Nerves of brass, you blackguard. Come here right to the house where she died and all. Bloody nerve—”

“There is no need to shout, Mr. Ryan. I told you why I came. This.”

That was the new voice. American. Not really American. As Irish as everyone, but sometimes American. This was too unusual to miss. Brian forgot his anger at being sent to his room so early, forgot his tantrum that had sent him to the closet, into the darkness to bite his knuckles and cry where no one could see or hear him.

On tiptoes he crossed the tiny room, the wood cold on his bare feet, warm on the rag rug by the door. Five years old, he could look out through the keyhole now without standing on a book. Pressed his eye close.

“This letter came a few weeks back.” The man with the accent had red hair, freckles. He looked angry as he waved the piece of paper. “And there’s the postmark on the envelope. Right here, Tara, this village. Do you want to know what it says?”

“Get out,” the heavy, phlegmy voice rumbled, followed by a deep cough. His grandfather. Still smoked twenty a day. “Can you not understand the simple words – you’re not wanted here.”

The newcomer slumped back, sighed. “I know that, Mr. Ryan, and I don’t wish to argue with you. I just want to know if these allegations are true. This person, whoever it was, has written that Eileen is dead—”

“True enough, by God – and you killed her!” Uncle Seamus was losing his temper. Brian wondered if he would hit this man the same way he hit him.

“That would be difficult since I haven’t seen Eileen in over five years.”

“But you saw her once too often, you twisting sonofabitch. Got her with child, ran out, left her here with her shame. And her bastard.”

“That’s not quite true – nor is it relevant.”

“Get away with your fancy words!”

“No, not until I’ve seen the boy.”

“I’ll see you in hell first!”

There was a scrape and crash as a chair went over. Brian clutched the doorknob. He knew that word well enough. Bastard. That was him, that’s what the boys called him. What had this to do with the man in the parlor? He did not know; he had to find out. He would be beaten if he did. It didn’t matter. He turned the knob and pushed.

The door flew back and crashed against the wall and he stood in the doorway. Everything stopped. There was Grandfer on the couch, torn gray sweater, the cigarette end in his lips sending a curl of smoke into his half-closed eye. Uncle Seamus, fists clenched, the fallen chair behind him, his face red and exploding.

And the newcomer. Tall, well dressed, suit and tie. His shoes were black and shiny. He looked down at the boy, his face twisted with strong emotions.

“Hello, Brian,” he said, ever so quietly.

“Watch out!” Brian shouted.

Too late. His uncle’s fist, hard from years in the mine, caught the man high on the face, knocked him to the floor. Brian thought at first that it was going to be one of those fights, like on Saturday night outside the pub, but it wasn’t going to be like that, not this time. The newcomer touched his hand to his cheek, looked at the blood, climbed to his feet.

“All right, Seamus, maybe I deserved that. But just that once. Put your fists down, man, and show some intelligence. I’ve seen the boy and he’s seen me. What’s done is done. It’s his future I care about – not the past.”

“Look at the two of them,” Grandfer muttered, holding back a cough. “Alike as two pennies, the red hair and all.” His temper changed abruptly and he waved his arms, sparks flying from his cigarette. “Get back into your room, boy! Nothing here for you to see – nothing here for you to hear.

Inside before you feel my hand.”

* * *

Incomplete, disjointed, adrift in time. Memories, long forgotten, disconnected. Surrounded and separated by blackness. Why was it still dark? Paddy Delaney. His father.

Like slides in a cinema, flickering and quick, too quick to see what was happening. The blackness. The slides, suddenly clear again.

A loud roaring, the window before him bigger than any window he had seen before, bigger even than a shop window. He clutched tightly at the man’s hand. Frightened, it was all so strange.

“That’s our plane,” Patrick Delaney said. “The big green one there with the bump on top.”

“747-8100. I seen a pitcher in the paper. Can we go into it now?”

“Very soon – as soon as they call it. We’ll be the first ones aboard.”

“And I’m not gonna go back to Tara?”

“Only if you want to.”

“No. I hate them.” He sniffled and wiped his nose with the back of his hand. Looked up at the tall man at his side. “You knew my mother?”

“I knew her very well. I wanted to marry her but – there were reasons we couldn’t get married. When you are older you will understand.”

“But – you’re my father?”

“Yes, Brian, I am your father.”

He had asked the question many times before, never really sure that he would really get the right answer. Now, here, in the airport with the big green plane before them, he believed it at last. And with the belief something seemed to swell up and burst inside him and tears welled out and ran down his face.

“I never, never want to go back.”

His father was on his knees, holding him so tightly that he could barely breathe – but that was all right. Everything was all right. He smiled and tasted the salt tears, smiling and crying at the same time and unable to stop.