Lest You Remember
What is a memory? What is this thing, as ephemeral as a key fob’s whereabouts and as enduring as a brutal childhood? Is it the predisposition of certain neurons to fire in a certain sequence? A discrete and repeatable distribution of electrical activity? No more than a specific—but malleable and often temporary—spatiotemporal distribution of chemicals? How are memories kept and lost in the soft, wet tissues of the brain? How do we form, store, and protect these integral parts of our being? And how can we ‘forget’ something, only to have it recalled many years later, involuntarily, perhaps at the bidding of a song or a scent?
These questions are fundamental to the nature of Self, for each person’s identity is fused to, if not identical to, a unique set of recollections. With different memories, we would be different people; hence, the nature of memory is a mystery at the core of ‘human-being.’ A riddle wrapped, no doubt, in mysterious molecular signals, and buried, perhaps, in the hidden neurons of the hippocampus—itself a component of that enigmatic, primitive part of the nervous system called the ‘palaeomammalian brain.’ But knowing the location of the answer is not the same as knowing the answer, particularly when the location is a nugget of wet tissue containing a few billion neurons.
Yes indeed, when we study the brain, we see the brain attempting to understand itself. Sometimes I ask myself if this is even theoretically possible. Can a hammer nail itself down? It could be that our efforts are futile, in the sense that full understanding of the molecular basis of human cognition may be forever elusive. Nevertheless, in our lab, here at the Cambridge Unit for Advanced Cognitive Science (CUACS), we are probing this enigma. Does that make us more fools than angels? Well, there’d be few fools as clever. In any case, we think we are close to answering this most critical of mysteries. For we can now implant memories.
Yes: we can implant memories.
You’d have to work in the field to know how daring, how unprecedented the concept held in that statement is. I can almost hear the screams of protest from the research community, the resentment of puny minds overtaken by greatness! Listen: we can give a rat the ability to unerringly navigate a maze it has never seen. Is this not the same as implanting a memory? Unconvinced? Then consider our technique. We take a rat, and allow it to become familiar with a maze in which some food is cached. It is not an easy maze; there are no cues to trigger left or right turns; the rat simply has to know the way. We help it learn, of course; for example, although only one route delivers rewards, others lead to degrees of discomfort, perhaps pain. And after a while, the rat becomes entrained. It finds its way to the reward quickly and unerringly, with no hesitation or false turns. In other words, it has developed a memory of the maze.
But what does that mean, to ‘develop a memory?’ Evidently, something has changed in its brain; something is there that previously was not. And for many years, that was all one could say about the entrainment process; somehow, something has changed, and the maze can be navigated. But science will progress, and for some time now, by scanning specific types and locations of brain activity before and after entrainment, we at CUACS have been able to locate this memory, this specific, entrainment-related change. Yes, physically locate it, and define it as a precise set of IF/THEN-type neuronal firing sequences that can be recorded as digital data. This is an extraordinary advance in itself; it is like the first recordings of an unknown syntax. Nevertheless, this step, while necessary, was insufficient to satisfy our ambitions.
For we next asked ourselves this: having defined a specific memory in terms of neuro-electrical tendencies in a particular region, what if the same tendencies are provided to a different brain? Will not a different brain with the same firing predispositions, in the same anatomical-functional location, have the same memory? Obviously, we addressed this question by direct experiment; such a question cannot be posed without its answer being pursued. So, we recorded the specific maze-memories—the location-specific neuronal firing patterns—from entrained rats. We then imprinted these neuro-electrical tendencies onto equivalent regions of the brains of naïve rats: rats that have never seen the maze. And the results are compelling. All memory recipients—all of them—find the food significantly more quickly than the controls. Furthermore, some memory recipients, maybe 15%, find the food reward immediately, without any wrong turns whatsoever. What information could we be transferring other than memory? The experimental results permit no other conclusion. The data are unambiguous. Therefore, I say again: we can implant memories.
As you would expect from CUACS, this result is the first of its kind. And we are very proud of what we have achieved. Refining the technique from its first application in nematodes to the relative complexity of the rat brain was the labor of years. The method is a little abstruse, but mainly involves attention to predispositions in neural pathways linked to the hippocampus. Recordings are made using a combination of functional magnetic resonance imaging and one or two other techniques. The imprinting of memories in the naïve brain is done using a system of our own invention, which we are not going to disclose prior to publication. The spectacular success of this method, its reliability and reproducibility, took even the ego of its inventor by surprise. But using it is not without risk; it requires a delicate and highly skilled hand. You have to be careful. Especially with vertebrates. Yes, there’s less room for error in the higher organisms. If you use the wrong settings, you over-write the autonomic nervous system. In other words, all the neural signals that tell the body to keep breathing and pumping blood and digesting—they all cease. Because you’ve replaced them, these instructions for survival, with the memory of a maze. The memory recipient’s lungs and heart just stop. We had a few dead rats, I can tell you, before we figured out where we were going wrong. It got embarrassing. But that’s all done and dusted now. We’re lucky to have a post-doc, Jon Adams, who’s been with us from the start of this project. He can really make the machine sing and the neurons dance. We’d be in a mess if he ever left; it could take years to rebuild that kind of expertise.
So the technology, the technique, is well-understood, albeit subtle and difficult. The principle has been well and truly proven. The real issue at present is that we have no idea of the subjective experience of the rats. What is it like to have another’s memory? Is it recognizably exogenous? Or is it just like your own? If it is now ‘your’ memory, how deep is your experience of it? I mean, is it just factual (this was my teddy), or does it carry the complex mixture of emotions attached to a real memory? This was my Teddy, to whom I went when all was black in my childish world, and who soaked up my tears; and I loved him. In the former case, we transfer dry knowledge; in the latter, we provide something that drags at the soul and pulls at the heart. But which is it? We just don’t know. That’s why we are going into humans. Unofficially, that is; there’s no ethical approval for this experiment. In fact, it’s illegal. But it’s just too interesting not to do.
OK, let me be honest. It is not just scientific curiosity that motivates us. This kind of work could make somebody’s career. You can be set up for life, just by being in the right place at the right time. Look at Watson and Crick, and their work on DNA. They received a Nobel Prize for that, and unending fame. Permanent seats in the first-class carriage of the gravy train. But would either of them be described as a genius? Hardly. Life rolled the dice, and their numbers came up. Don’t get me wrong, they did well; they seized the opportunity, and not everybody would have done that. But there are cleverer and harder-working people who have no Nobel Prize. That’s for sure. Some of them don’t even have a job. Equally, there are some Nobel recipients who are less deserving still than Watson and Crick. That’s life. There’s no logic to it. There’s no fairness or rationale. It’s just a numbers game. All you can do is work hard, and try to be in the right place at the right time. And in terms of medical research, the neurophysiology of the human mind is the place to be right now. There’s a Prize for Medicine at stake here, I’m sure of it, and I want it. It will be the first Nobel to come out of CUACS research. That’s why it’s so frustrating that the regulators won’t approve our first-in-man study. Typical short-sighted, sour-grapes reaction. Sometimes I think I’d rather be in China. There’s none of that ethical approval nonsense there. No stuffed-shirt establishment to appease. In China, if there’s the money to do it, it gets done. End of. UK science needs to learn from that before it gets overtaken. Well, I’m not going to let my research be hampered by pompous jobsworthies. I’m proceeding without approval. All the great scientists have cut corners, taken risks, and tested hypotheses on themselves. It’s a fine tradition, from Newton on. And I am proud to be a part of it.
So we’re going into man. Tonight. Now that it’s gone 9 PM, and everyone else has clocked off. Yes, it’s a bit late in the day, and I’m starting to slow down a bit, but people in biomedical research work long hours. You have to. If you don’t do something pretty special in your current three-year contract, you don’t get another one. It’s brutal; three years of cutting-edge molecular biology can leave you qualified for nothing more than a lifetime of telesales and gardening. That’s partly why I’m taking this risk. If it comes off, I’ll never have to beg for a new contract or worry about grant funding again. But it’s totally illegal. That’s why we have to do this after hours. We’d be immediately sacked if anyone found out. Although I suspect that the CUACS Directorate would be less concerned about the illegality, per se, than by the attendant bad publicity. They’ve had enough scandals in recent times, and would be infuriated by further transgressions of regulatory guidelines and laws. So I am not just putting my head on the block; I am also handing a sharpened axe to a vindictive executioner.
This knowledge contributes to the hammering of my pulse; my career has reached an inflection point. Either I fly, or I crash and burn. But the squirting adrenalin and sweating is also a response to the very real risks of the procedure itself. Sure, we’ve done it in rats. But going from rats to man is a big step. We think it will be OK. It ought to be. But, frankly, we don’t know. The memory uploading procedure is not an issue, of course. Nobody’s brain gets altered in that step; it’s like leaving a voicemail. And it doesn’t require as much skill as the imprinting step. That’s why Jon is OK with me recording his test memory. It can’t go wrong. The idea is that Jon memorizes a simple picture, one that I haven’t seen, but one that I will recognize. A shape rather than a squiggle. I then record the changes in his temporal lobe predispositions that have occurred as a consequence of memorizing said picture. In other words, I will scan specific changes in a specific region of his brain; changes that represent his memory of the picture. That part of the operation is risk-free. It’s no more of a big deal than spitting into a cup. It’s the next bit that is difficult—the part where we swap roles, and I become the subject—where Jon implants his recorded memory into my brain.
You might think that it would be easier to do in a man than a rat. After all, the target is so much bigger; and the subject is co-operative. But co-operation is not an issue, for, like the rat, the human subject is immobilized; in particular, the skull is anchored in a retention cage. This is a semicircle of pale metal that sits over the head and is itself immovably attached to the bench on which the subject is lying. Small titanium screws penetrate the semicircle and are rotated along their thread, through the skin, finding shallow anchorage in the bone. The cage makes movement from the neck up utterly impossible; so the subject can’t not co-operate, or rather, it makes no difference whether he does or he doesn’t. And, with belt and braces philosophy, the rest of the body is also restrained. Of course, the object is only the safety of the subject, but it’s uncomfortable being tied to a bench under a crown of silver thorns. And targeting precise neuroanatomical regions is not the issue either. The brain may be hidden behind its bony shell, but its anatomy holds no secrets for us. Furthermore, our computer-guided neural imprinter has nanometer precision. We could write the entire text of Hamlet on the head of a pin, and still leave enough room for a brace of angels to dance.
No, the issues are not targeting or co-operation, but complexity. A human brain is much more complicated than a rat’s. The neurons are more interconnected at more levels and in more ways. And some neurons may be multifunctional; so by altering a memory synapse you might also, who knows, subtly alter numerical ability. More dangerous still is the prospect that what we believe to be just a depository for a specific memory is actually far more fundamental. In this case, the experiment could, for example, completely wipe my short-term memory. Life would be impossible. I would not understand my present; I would exist in a bubble of confusion, reaching always for an unattainable past. That permanently, unimaginably crippled existence would be the result of a small miscalculation, just a small one. A larger one, one that wiped out the functions of, say, the medulla oblongata—which controls functions such as breathing and heart rate—would just stop my brain, and with it, the rest of me—heart, lungs, bowels, everything. Just like the first few rats.
So yes, I’d be lying if I said I wasn’t nervous. We’ve tried to manage the risks, but management is not the same as elimination. Even the restraining bench, with its straps and retention cage, like something from a Victorian nightmare, doesn’t remove all risk. But I’ve seen Jon at work; he can perform the most delicate of operations. I have complete confidence in him. And he is pretty damn sure of himself too. After all, he was originally going to implant the memories into his own wife. Yes, Liz was going to be the memory recipient, but she’s not here. Apparently she’s left him—gone back to Australia. Which would explain why Jon has been looking a bit grim and harassed all week, losing his rag over the smallest things. I know those two had a very, er, passionate relationship, so I’m not too surprised at the outcome. Anyway, it’s her loss, and my gain. I’ll be able to write the paper from a personal, directly experiential perspective, which will have so much more impact. Yes, I’ll be giving the keynote talk at every neurobiological conference for the next five years. Here comes the gravy train. I can almost hear it.
That’s what I keep thinking of as I take the neuronal imprinter readings. Jon is lying inside the machine’s tunnel, holding a white A4 envelope. I can’t see him, of course—I stay out of the room when the machine is on—but I know he has the envelope containing the test picture. I look at the readings on the computer screen, a 3-D representation of the transient de- and re-polarizations of Jon’s memories. I flip it around, and look at it from different angles. The detail is good: a nice clean recording, almost beautiful, a pattern of sorts. Actually, more like a sculpture, a delicate sculpture, spun from the stuff of dreams and captured in a frozen instant.
“OK,” I say, through the intercom, “I’ve got the base readings; you can memorize the picture now.”
There’s no answer; suddenly, for no good reason, I’m worried.
“Jon?” I say. “Can you hear me? You can open the envelope now.”
“Alright!” he snaps back at me. “I heard you the first bloody time.”
Moody sod, I think. But I don’t say anything; I just don’t care. I’ll put up with Jon in exchange for a ticket on the gravy train, for sure. I look at Jon’s readings on the monitor. The machine is focusing on a particular region that is exhibiting discrete, regular changes. There it is, I think, just the ticket. I give the statistics software a few minutes to remove background noise from the signal. Then, when I’m sure we’ve got the cleanest data we can, I turn the machine off and call Jon in. We look at the readings together. The changes are located where we would expect them to be, based on our knowledge of the neuroanatomical location of human memory. The data also look somewhat similar to the rat recordings, which is encouraging. However, there are some differences too. The rat firing patterns were very discrete and defined: crisp readings, with clear-cut edges. Jon’s are a bit more diffuse. But you’d kind of expect that; humans are more complex than rats. It’s a minor variation, and I’m happy to proceed.
However, to my surprise, Jon seems a bit equivocal. A muscle in his jaw is clenching, on and off, on and off.
“You sure about this?” he growls. “It looks different from the rat data. Looks a bit messy, like it’s got multiple cross-overs.”
That’s the thing about post-docs. They’re at this awkward stage: beyond PhD, but not yet lecturers. You have to be tolerant.
“Don’t worry,” I say. “The human brain has multiple connections allowing complex cross-talk. The pattern is as I would expect.”
This isn’t quite true, but it serves as a timely reminder to Jon: I’m the junior lecturer, not you. Know your place, chum.
“It’s your brain,” he says, in his charmless way.
Too right, I think; my brain, and my gravy train. But Jon still looks tense and worried. I guess the momentous nature of what we are about to achieve has finally sunk in. I get on the restraining bench before he can start to raise any more objections.
“Come on,” I say breezily. “Get on with it.”
And he does, sullen as ever. He restrains my body first, before immobilizing my head. The muscle in his jaw is still going tic, tic, tic. The immobilizing straps are made of the kind of fabric—like heavy-duty canvas—that they use on rucksacks; the same design of plastic buckles, too. He pulls them tight, one across my shins, another across my thighs; others over my waist and chest, and smaller ones for wrists and biceps. I try to wriggle, and find I can’t move. I breathe deeply, fighting the claustrophobia. Jon looks at me sullenly, almost hostile.
“Why do you keep saying that, anyway?” he snarls.
I didn’t realize I had been saying anything.
“Saying what?” I ask.
“Gravy train, gravy train. Over and over.” He looks at me. “What do you mean by it? What’s the matter with you?”
He places the retention cage over my forehead and tightens the nuts that hold it to the bench.
“Sorry,” I say. “I’ll shut up.”
“Yes, do,” said Jon. “It’s bloody annoying.”
He inserts the titanium screws through the retention cage framework. There are ten of them. Two above each ear, two at each temple, and two in the center of the forehead. He tightens them until they are touching the skin. Then he pauses and looks at me. There’s something eating him; I can see more of the whites of his eyes than usual.
“This is the fun bit,” I say.
Jon doesn’t answer, just stares at me. It’s getting creepy, but then he seems to come to a decision, and nods. And he starts tightening the screws. I feel the thread biting into the bone, ten points of almost unendurable pressure. I just didn’t think it would hurt this much. The train had better be extraordinarily luxurious, when it turns up. Jon dabs at my face with something, and then holds it up. A bloody tissue.
“Gravy,” he says. “Yum, yum.”
One corner of his mouth is lifted up in a sardonic half-smile. I should have known he would enjoy this bit, the sadist. I ignore him and focus on the extra monitor, which we’ve set above the bench so I can see it from the retention cage. I can see the scan of my brain activity on the screen. This reassures me and helps me control the rising panic induced by immobilization. A tracery of green and red—my fears, my hopes and desires, strung out in false colors on the computer screen. They are beautiful. On the bottom left of the screen is the status window. It gives the message ‘Awaiting input’ over and over. Jon must be about to trigger the imprinting process. What’s taking him so long? Any minute now, surely. OK, he’s started. I hear the processor cooling fans going into overdrive, and on the screen the window changes to ‘Inputting…’ No sensation, at least nothing that I can feel over the pain of the screws cutting into my skull. This had better work.
There it is! I get it just after the status window changes to ‘Input complete.’ We have made history! At least, I think we have. Time to analyze the data. Does my implanted memory correspond with Jon’s memorized picture? I try to recall what I first grasped. It is just imagery, in fact a confusion of images. Strongest are a plate, knife, and fork. Jon is standing over me now, looking down. He looks scared.
“Are you OK? What did you see?”
I try to smile, but I am almost hyperventilating.
“I think it worked,” I gasp. “Plate, knife, and fork? On a table?”
Jon holds up his picture. Plate, knife, and fork! Success! He grins, relieved.
But there’s something different about the picture. Or rather, different about my memory. This is interesting. We should note this down. Perhaps memories are modulated by the recipient. Because I ‘remember’ a large kitchen knife with a serrated edge, not a table knife. And it’s not a simple, stylized picture that I see. It’s an image of a table. It’s the table in Jon’s kitchen, I know it is. I’ve never been there, but I remember it. And my knife has blood on it. And on my plate, I see it clearly, Liz’s severed head. Dear God, Jon, what have you done?
I am still trapped in the retention cage. I cannot move. Jon looks down at me. As our eyes meet, I see that he knows what I remember. And we share also the knowledge of what he is about to do, what he now must do. He goes to the machine. I cannot see him, but I know what those sounds mean. He is altering the settings, and aiming the field at my medulla oblongata.
I see my thoughts lit up on the screen, a beautiful filigree of electrical pulses, my soul’s glowing outline.