The Fifth Profession

past ten years, and the more I learn, the more I'm baffled…Describe what happens when you remember a past event.”

Savage and Akira hesitated.

Rachel gestured. “Well, it's sort of like seeing a movie inside my head.”

“That's how most people describe it. We experience an event, and it seems as though our brain works like a camera, retaining a series of images of that event. The more we experience, the more films we store in our brain. When circumstances require, when we need to review the past to understand the present, we select an appropriate reel and view it on a mental screen. Of course, we take for granted that the films are permanent records, as immutable as a movie.”

Rachel nodded.

“But a movie isn't permanent. It cracks. It discolors. Scenes can be eliminated. What's more, we're explaining memory by means of analogy. There aren't films in our brain. There isn't a screen. We merely imagine there are. And memory becomes even harder to explain when we pass from concrete events to learned abstractions. When I think of the mathematical principle of pi, I don't see a film in my head. I somehow, intuitively, understand what pi signifies. And when I think of an abstract word such as ‘honor,’ I don't see a film. I just know what ‘honor’ means. Why am I able to recall and understand these abstractions?”

“Do you have an answer?” Savage's chest ached.

“The prevailing theory is that memories are somehow encoded throughout the brain in the neurons. These billions of I nerves-the theory goes-not only transmit electricity and information but also retain the information they transmit. The analogy of a computer is frequently used to illustrate the process, but again, as with the illusion that we have a movie screen in our heads, an analogy is not an explanation. Our memory system is infinitely more complex than any computer. For one thing, the neurons seem capable of transferring information from one network to another, thus protecting certain memories if a portion of the brain is damaged. For another, there are two types of memory-short term and long term-and their relationship is paradoxical. ‘Short term’ refers to temporary memories of recently acquired but unimportant information. The telephone number of my dentist, for example. If I need to make an appointment, I look up the number, remember it long enough to call his office, and immediately forget it until the next time I need an appointment and repeat the process. ‘Long term’ refers to lasting memories of necessary information: the telephone number for my home. What physical mechanism causes my dentist's number to be easily forgotten but not my own? And why, in certain types of amnesia, is a patient unable to remember any recent event, whether trivial or important, while at the same time he can recall in vivid detail minor long-forgotten events from forty years ago? No one understands the process.”

“What do you believe?” Akira asked.

“A musical by Lerner and Loewe.”

“I don't…”

“Gigi. Maurice Chevalier and Hermione Gingold sing a wonderful song, I Remember It Well.’ Their characters are former lovers recalling when they met. ‘We went here.’ ‘No, we went there.’ ‘You wore this dress.’ ‘No, I wore that.’‘Ah, yes, I remember it well.’ But they don't. Sure, the point of the song is that old age has made them forget. The trouble is, I'm not sure the rest of us don't forget also. A lot of specifics. And sooner than we realize. Dr. Weinberg and I have a sentimental tradition. Every Saturday night, when Max and I aren't on call, we and our wives see a movie and then go to dinner. After the stress of the week, we look forward to the distraction. Yesterday, Max fondly remembered a film the four of us had seen together. ‘But Max,’ I said, ‘I saw that movie on cable television, not in a theater.’ ‘No,’ Max insisted, ‘the four of us saw it downtown.’ ‘No,’ I told him, ‘I was at a conference that weekend. You, your wife, and mine went to see the film without me.’ We questioned our wives, who didn't remember the circumstances. We still don't know the truth.”

“Of course,” Savage said. “You just explained short-term memory doesn't last.”

“But where does short term end and long term begin? And how can we be sure that long-term memory truly endures? The basic issue is the limitation of consciousness. We're capable of knowing we remember only if we remember. We can't be aware of something we've forgotten… Describe the future.”

“I can't. The future doesn't exist,” Savage said.

“No more than the past, though memory gives us the illusion the past does exist-in our minds. It's my opinion that our memories don't remain permanent after they're encoded. I believe our memories are constantly changing, details being altered, added, and subtracted. In effect, we each create a version of the past. The discrepancies are usually insignificant. After all, what difference does it make if Max and I saw that movie together or separately? But on occasion, the discrepancies are critical. Max once had a neurotic female patient who as a child had repeatedly been abused by her father. She'd sublimated her nightmarish memories and imagined an idyllic youth with a gentle, loving father. To cure her neuroses, Max had to teach her to discard her false memory and recognize the horrors she'd experienced.”

“False memory,” Savage said. “Jamais vu.But ourfalse memory isn't caused by psychological problems. Our brain scans suggest someone surgically altered our ability to remember. Is that possible?”

“If you mean, would I be able to do it, the answer is no, and I'm not aware of any other neurosurgeon who could do it, either. But is it possible? Yes. Theoretically. Though even if I knew how to do it, I wouldn't. It's called psychosurgery. It alters your personality, and except for a few procedures- an excision of brain tissue to prevent an epileptic from having seizures, or a lobotomy to stop self-destructive impulses-it isn't ethical.”

“But how, in theory, would you do it?” Rachel asked.

Santizo looked reluctant.

“Please.”

“I pride myself on being curious, but sometimes, against my nature, I've refused to investigate intriguing cerebral phenomena. When necessary, I've inserted electrodes into the brains of my patients. I've asked them to describe what they sensed.”

“Wait,” Akira said. “How could they describe the effects if their brains were exposed? They'd be unconscious.”

“Ah,” Santizo said. “I take too much for granted. I skip too many steps. I'm too used to dealing with fellow neurosurgeons. Obviously you think exposing the brain is the same as exposing the heart. I'll emphasize a former remark. The brain-our sense receptor-does notitselfhave a sense receptor. It doesn't feel pain. Using a local anesthetic to prevent the skull from transmitting pain, I can remove a portion of bone and expose the great mystery. Inserting an electrode into the brain, I can make the patient smell oranges that don't exist. I can make the patient hear music from his childhood. I can make him taste apples. I can make him have an orgasm. I can manipulate his sense receptors until he's convinced he's on a sailboat, the sun on his face, the wind in his hair, hearing waves crash, skirting Australia's Great Barrier Reef-a vacation he experienced years before.”

“But would he remember the illusions you caused?” Rachel asked.

“Of course. Just as he'd remember the true vivid event, the operation.”

“So that explains what happened,” Savage said.

“To you and your friend? Not at all,” Santizo said. “What I've just described is an activation of the patient's memory by means of an electronic stimulation to various neurons. But youhave memories of events that apparently…”

“Never happened,” Akira said. “So why do we remember them?”

“I told you, it's only a theory,” Santizo said. “But if I expose the left temporal lobe of your brain…and if I stimulate your neurons with electrodes… if I describe in detail what you're supposed to remember, perhaps show you films or even have actors dramatize the fictional events…if I administer amphetamines to encourage the learning process… and when I'm finished, if I use the electrode to scar selected neurons, to impair your memory of the operation…you'll remember what never happened and forget what did happen.”