Realtime Interrupt

by James P. Hogan

  "That has to be an acronym for something."

  "Miniaturized Motor Intercept Collar. You'll see why in a moment." Corrigan looked over at Shipley. "How are we doing, Eric?"

  "Just about there. . . ." Shipley entered a final command, and the silhouette of a human female figure appeared, centered in the screen. "Okay," Shipley said. Evelyn looked at Corrigan questioningly—mainly by moving her eyes, since the collar impeded head movement.

  "Move one of your arms," Corrigan directed.

  Evelyn raised an arm, and the figure on the screen did the same thing. She raised both arms, then swung them in circles; the figure duplicated the motion. She smiled, enjoying the spectacle. "Hey, I'm impressed," she said, smiling and talking through her teeth.

  "You can move about," Corrigan said. "Watch the cable, though."

  Evelyn stepped forward, then a pace sideways, cautiously at first; then, getting really into the experience, she laughed and broke into a short routine of dance steps and gestures. The figure on the screen mimicked everything faithfully. "I had no idea it would be so smooth."

  Her movements were not being interpreted from TV images, position-detectors in suits, body-mounted light-emitters, or by any of the other familiar methods for encrypting human physical motion directly into computers. Instead, the collar surrounding Evelyn's neck and lower brain stem was picking up the motor output signals on their way down to the spinal cord to direct her musculature system. The same signals were being fed to the programs controlling the figure dancing on the screen—which Shipley had adjusted to superficially resemble Evelyn in shape and body proportions.

  Evelyn spent more time experimenting, showing a lot of interest, asking some good questions. The figure's head didn't move, she discovered, since the system only picked up signals on their way down from the brain. It didn't matter very much—she was hardly able to move her own head anyway. As an input interface it was ahead of anything that she had realized existed.

  "I'm surprised that it's in your museum already," she said as Shipley switched off the equipment and Corrigan helped her remove the collar.

  "It's been three years," Corrigan said.

  "That still seems soon."

  "The accelerating rate of progress. It got overtaken. We're into a new version now."

  "Do I get to see it?"

  "Yes, but not here. We'll have to go over to the labs. It gets better."

  They went through an exit at the rear of the building and followed a path by a lawn between the several other buildings and parking lots forming the rest of the complex. The architecture was a mixture of old brick-and-stone and new concrete-and-glass, standing on the site of a former steel plant. The ovens and furnaces had gone, but the serviceable buildings had been restored and converted into office and laboratory space, and a number of brand-new facilities erected in the spaces created by the demolitions.

  For the past several years, Evelyn had been working as a researcher at Harvard on noninvasive stimulation of the visual system. The field was a development from early experiments in the sixties by animal researchers seeking ways of exciting selected brain centers without the need of surgically implanted electrodes, which tended to interfere with the processes that they were supposed to measure. The result was a variety of techniques using additive external electric fields, summation of beams of certain electromagnetic frequencies for which the skull and its underlying cerebral tissues were found to be transparent, ultrasonic waves and pulses, and other approaches, all focused upon the common goal of controlling the firing of selected brain patterns painlessly and without intrusion, from outside the skull.

  Collectively the subject was known as "DINS" (DIrect Neural Stimulation) technology. This was also Shipley's area of expertise, and he needed another specialist. Hence, Evelyn took it that, assuming that she was made an offer and accepted it; she would be working primarily with him rather than with Corrigan. Nevertheless, Corrigan seemed to have taken charge of the interview process. Evelyn attributed it to his natural flamboyance and enthusiasm. Shipley didn't seem to mind, and it added to the image of irrepressible Irish roguishness that Evelyn had begun to form of Corrigan.

  They entered one of the older buildings and went up a level and a short distance along a corridor, past a door marked J. M. CORRIGAN, to double doors inset with small glass panes. Inside was a large room cluttered with the paraphernalia of electronics R & D labs anywhere: cabinets and equipment racks draped with tangles of cable, making it difficult to tell which piece of hardware was associated with what; several office desks, littered with books and papers; a wall of metal shelving holding boxes, supplies, unidentifiable gadgets in various stages of assembly or dismemberment; a workbench along one wall, with tools on a pegboard above, soldering irons on stands, more shelves and drawers of electrical components, oscilloscopes and electronic test equipment. A couple of techs in shirts and jeans were working around a rig on the far side; another was wiring up a connector on some kind of assembly stripped down on the bench; a girl was operating a terminal at one of the desks.

  Corrigan led the way over to a cluster of racks and cubicles on the far side. A tall, loose-limbed figure with a generous mane of neck-length yellow hair, clad in a loose sweater and tan denims, was sprawled in front of a console. It was a typical lab-lashup, makeshift affair, consisting of several monitor screens, some electronics, and a panel, all fitted in a framework bolted to the body of an old steel desk. He unfolded himself in a lazy, unhurried movement and sat up to greet the arrivals with a grin.

  "How are we doing here, Tom?" Corrigan inquired.

  "All set."

  "This is the group's software supervisor, Tom Hatcher."

  "Hi, Tom."

  "Tom, this is Evelyn Vance, that I told you about. We've just been across in the museum and seen MIMIC." And to Evelyn: "Now we want to bring you up to date on what we're doing now."

  "So you're the lady who's gonna be joining this crazy outfit, eh?" Hatcher had a slow, easy southwestern drawl that went with his manner.

  "We'll see what happens, anyway," Evelyn said.

  There was another chair, upholstered in black and built upon a tubular steel frame, positioned in front and to one side of the console, where it could be observed by the console operator. It had a collar structure built in front of the headrest, heavier and more intricate than the one that MIMIC used, and hinged into two halves to admit the wearer. Evelyn commented that it looked like a pilot's seat. Shipley confirmed that it was from an Air Force jet.

  In front of the chair was a flat metal surface a foot or so square, bounded on the far side by vertical glass plates set at an angle like an opened book. Behind the plates was a collection of shiny tubes and mirrors that Evelyn recognized as the laser and optics of a hologram projector.

  "That's your next ride," Corrigan said. "Take a seat."

  "You mean I don't get to dance this time?"

  "Oh, sure you will. I told you, it gets better."

  Shipley held some of the trailing cables aside and beckoned Evelyn toward the chair. "It looks as if I'm going to be electrocuted," she said, stepping forward.

  "Medium, rare, or well-done?" Hatcher asked from the console. They all laughed.

  The headrest, Evelyn saw as she sat down, was in fact an integral part of the collar unit itself. Corrigan moved over to stand by Hatcher, and they went into a technical exchange about loop gains and parameter settings.

  "Where did you get your background in DINS?" she asked Shipley as he closed the collar and began securing connections—partly from curiosity, partly to get him to talk more.

  "Oh, I used to be with part of the SDI program—using active optics to precorrect laser beams for transmission distortion." He had a deep, gruff, but not unkindly voice. Corrigan could be fun to have around, but when it came to more serious business, she hoped that she would be working with Shipley. He went on. "That needed fast algorithms to compute complex signal patterns in real time, and the math turned out to be ideal for generati
ng brain-stimulation sequences, too. . . . Now you'll need to hush up so I can position the lateral pads."

  The front portion of the collar immobilized her jaw, making this a lot more constraining than MIMIC and fixing her gaze on the holo-projection space above the metal plate.

  "Okay, Evelyn, relax," Corrigan said, turning to face her. "You might experience a few funny feelings at first, but don't worry about it. This time we'll also be injecting sensations into your neural centers. Your brain won't be able to tell that they're not coming in via the sensory system. But first we have to calibrate to your particular ranges of scale and sensitivity. It only takes a minute."

  Suddenly, Evelyn's body went numb from the neck down, as if she had undergone an instant spinal block. Then she felt a pins-and-needles sensation in her arms and legs, especially in the fingertips. When she tried wriggling them, they wouldn't respond. After a few seconds this faded, and more normal feelings returned, but blurred somehow, as if she were suspended in molasses.

  Tom Hatches called across to her from the console. "Feel okay? Blink once for yes, twice for no, three times or make dentist noises in an emergency."

  She blinked, and could see the word "Yes" appear in green in a corner of one of Hatcher's screens. Evidently there was an eye tracker operating somewhere. A trained user would be able to communicate a whole vocabulary through eye movements.

  "Weird—kinda like an all-around water bed, but okay?" Hatches asked, checking.

  She blinked once.

  "Any discomfort?"

  She blinked twice. A red "No" on the screen confirmed it.

  "Now I want you to close your eyes and imagine that you're standing normally on the ground. Open your eyes when you start to feel heavy, then blink once when it's about right."

  Evelyn closed her eyes. An instant later, sensations came over her that were completely at odds with the situation she knew herself to be in. She could feel herself standing: feet pressing on the floor, back erect, arms hanging loosely. But too light. She felt precariously anchored, like a balloon just touching the ground, waiting for the first breath of wind to carry her away. But even as she thought it, her weight started to increase. Then she was twenty pounds too heavy, her spine sagging. She opened her eyes abruptly. The heaviness slackened off, reduced slowly . . . and she felt normal. She blinked.

  "Close your eyes again," Hatcher called. "Now imagine that you're holding a grapefruit in each hand. Lift them sideways to shoulder height, keeping your arms straight. Open your eyes when they get heavy. Blink once when they feel about right."

  The routine went the same as before.

  "Now raise both arms straight up over your head—without the grapefruits. . . . Point them straight forward from the shoulders. That's great. . . . Now raise each leg in turn, knee bent, until the thigh is horizontal. Okay. . . . Now keep your eyes closed and try walking a few steps."

  It was uncanny. Although Evelyn knew that she was sitting immobile with her head held in a restraint, she could feel herself walking across a floor. A bit lumpily and jerkily, it was true—but walking.

  "Does it feel quite right?" Hatcher's voice asked. Evelyn opened her eyes and blinked twice. "Tell me which of these corrections feels more normal. This? . . ." The discontinuity got worse, as if her leg were actually coming apart at the knee with each step. "Or this?" The feelings became smoother, almost right now. "Which was better?" Hatcher asked. "The first one?" Two blinks. "The second one?" One blink. After a couple more trials they had it perfect.

  "Okay." Corrigan pulled another chair close and sat down where Evelyn could see him. "MIMIC reads muscle-control information directly from the brain," he said. "DINS transmits information into the brain, bypassing the normal sensory apparatus. This is what happens when we combine the two together."

  A solid figure appeared in the holo-space, again female, wearing a simple red, loose-fitting dress. Once again, Evelyn could feel herself standing—in the same attitude as the figure, she realized after a second or two. She moved her eyes to look at Corrigan inquiringly. He nodded. She looked back at the holo-figure and made to move her arms. From the corner of her eye she could see that they remained motionless on the armrests of the chair. Instead, the hologram figure moved its arms. But unlike the case with MIMIC, this time Evelyn could actually feel it: the weight shifting and pressures in her joints altering as the shoulder and elbow angles changed, the tensions in her muscles—even the light rubbing of the dress material against her skin. Yet she knew that all the time she was sitting unmoving in a chair. It was unbelievable.

  "Still feel like a dance?" Corrigan asked, his eyes twinkling. "There's no cable to worry about this time. The motor outputs from your brain are being read as before with MIMIC, but a DINS signal is suppressing the onward transmission of them into the spine—like an externally induced anesthetic. At the same time, the computer is synthesizing the feedback signals that you ought to be experiencing, and injecting them back the other way."

  She walked the figure forward, then back, sideways and in circles, finally pirouetting and launching it into a series of twirls and minor acrobatics. At first it was odd to feel the figure's internal dynamics, yet at the same time to be observing it from a viewpoint outside. Corrigan watched, letting her get the hang of it. And then something changed suddenly, like the image of a wire cube reversing: the two bodies of sensation fused, and she was able to project herself inside, compensating unconsciously for the discrepancy in visual space.

  Corrigan sensed it. "Managed to make the flip?" he asked. She blinked at him once and forced a parody of a grin.

  "Try these," Hatcher's voice said. A flight of steps appeared in the display. Evelyn walked the figure over to them and began climbing. The sensations of her legs lifting and pushing, foot tilting and shifting the weight onto the ball, felt completely real.

  "The illusion is totally compelling if you close your eyes," Corrigan said.

  She did, and there was no longer any doubt: she was climbing a staircase. Already her thighs were starting to ache; and ache; and—surely not—she could feel her heartbeat accelerate from the effort, even slight perspiration. She opened her eyes again. They must have looked alarmed.

  "Don't worry," Corrigan said. "It's all simulated. You're bone dry and as relaxed as a sleeping baby. . . . So now you can see why MIMIC is in the museum already. This is its successor. We call it `Pinocchio.' What do you think?"

  * * *

  The three of them got down to specifics over lunch in the staff dining room at the top of the Executive Building, back at the front of the complex.

  "We're looking for more help on the neurophysiology side to go into the next step," Shipley said to Evelyn. He had said little since his few words about his SDI background, over in the IE Block, which Evelyn now knew was dedicated to various aspects of Interactive Environments. Now that they were into Shipley's territory, Corrigan no longer played the lead but was happy to sit back and let him get on with it. Evelyn sensed an easy, informal working relationship between them. She was finding the prospect of becoming a part of it increasingly appealing.

  "What is the next step?" she asked.

  "Pinocchio Two," Shipley replied. "As things stand, we're limited to the medulla. The system can't handle the Trigeminal and the Abducens. To go further, we want to bring somebody into the team with the kind of background you've had at Harvard—experience of connecting at the pons."

  Evelyn thought for a second. "That's why the face and eye movements didn't look right, isn't it?" she said. "I noticed when Tom went to close-up. I pulled a face deliberately, but the holo was still smiling."

  Shipley raised an eyebrow at Corrigan. Corrigan nodded that he liked what he was hearing. "You're right," Shipley told Evelyn. "The face is dubbed, purely for effect. The computer fills in what it thinks is appropriate."

  They were saying that Pinocchio's combined motor-intercept and DINS interface coupled in at the lowest region of the brain stem, the medulla oblongata, the main railroad
of the nervous system, where the seventh through twelfth of the body's twelve cranial nerves terminated. These were the nerves serving the body's voluntary and involuntary motor systems, along with the sense of balance, which was what enabled body movements and sensations to be reproduced in the ways that Evelyn had experienced. (These nerves also handled speech, taste, and hearing, but those faculties were not subjects of the current research.) The remaining functions—jaw and upper-face movements, ocular motion, vision, and smell—were handled by the first to sixth cranial nerves, which synapsed in higher regions of the brain.

  In particular, the fifth and sixth cranial nerves, known as the Trigeminal and the Abducens, both synapsed in the next region above the medulla oblongata: the pons. Shipley was saying that they now wanted to extend the coupling level up to the pons. Such a step could be in preparation for only one thing.

  "So the eventual intention must be to add vision," Evelyn concluded. That would require going further, to the thalamus, the next region above the pons. "You've already got hearing and speech, potentially, at the medulla—via the Acoustic, Glossopharyngeal, and Vagus. Extend from the pons to the thalamus, and you'll have it all: full-sensory direct-neural."

  "Except for olfactory," Shipley said, smiling faintly.

  "Oh, yes, of course." Evelyn checked herself. Smell was handled by the first cranial nerve. The most primitive of the senses, it was the only one to enter the brain above the thalamus and go directly into the cerebrum.

  "Well, now you know what we're up to here," Corrigan said, sitting back in his chair. He turned an inquiring eye to Shipley. Shipley returned a nod that he was satisfied. Corrigan looked back at Evelyn. "I think we've heard all we want to. To hell with the bureaucratic nonsense—that can catch up later. There's a place here for you if you want it. What do you say?"