Read The Future of the Mind Online
Authors: Michio Kaku
All these make for thrilling plot lines and box-office hits, but are any of them really possible, even in the future?
We know that amnesia is, indeed, possible, and that there are two basic types, depending on whether short- or long-term memory has been affected. “Retrograde amnesia” occurs when there is some trauma or damage to the
brain and preexisting memories are lost, usually dating from the event that caused the amnesia. This would be similar to the amnesia faced by Jason Bourne, who lost all memories from before he was left for dead in the water. Here the hippocampus is still intact, so new memories can be formed even though long-term memory has been damaged. “Anterograde amnesia” occurs when short-term memory is damaged, so the person has difficulty forming new memories after the event that caused the amnesia. Usually, amnesia may last for minutes to hours due to damage to the hippocampus. (Anterograde amnesia was featured prominently in the movie
Memento
, where a man is bent on revenge for the death of his wife. The problem, however, is that his memory lasts only about fifteen minutes, so he has to continually write messages on scraps of papers, photos, and even tattoos in order to remember the clues he has uncovered about the murderer. By painfully reading this trail of messages he has written to himself, he can accumulate crucial evidence that he would have soon forgotten.)
The point here is that memory loss dates back to the time of the trauma or disease, which would make the selective amnesia of Hollywood highly improbable. Movies like
Men in Black
assume that memories are stored sequentially, as in a hard disk, so you just hit the “erase” button after a designated point in time. However, we know that memories are actually broken up, with separate pieces stored in different places in the brain.
A FORGETFUL DRUG
Meanwhile, scientists are studying certain drugs that may erase traumatic memories that continue to haunt and disturb us. In 2009, Dutch scientists, led by Dr. Merel Kindt, announced that they had found new uses for an old drug called propranolol, which could act like a “miracle” drug to ease the pain associated with traumatic memories. The drug did not induce amnesia that begins at a specific point in time, but it did make the pain more manageable—and in just three days, the study claimed.
The discovery caused a flurry of headlines, in light of the thousands of victims who suffer from PTSD (post-traumatic stress disorder). Everyone from war veterans to victims of sexual abuse and horrific accidents could apparently find relief from their symptoms. But it also seemed to fly in the face of brain research, which shows that long-term memories are encoded
not electrically, but at the level of protein molecules. Recent experiments, however, suggest that recalling memories requires both the retrieval and then the reassembly of the memory, so that the protein structure might actually be rearranged in the process. In other words, recalling a memory actually changes it. This may be the reason why the drug works: propranolol is known to interfere with adrenaline absorption, a key in creating the long-lasting, vivid memories that often result from traumatic events. “
Propranolol sits on that nerve cell and blocks it. So adrenaline can be present, but it can’t do its job,” says Dr. James McGaugh of the University of California at Irvine. In other words, without adrenaline, the memory fades.
Controlled tests done on individuals with traumatic memories showed very promising results. But the drug hit a brick wall when it came to the ethics of erasing memory. Some ethicists did not dispute its effectiveness, but they frowned on the very idea of a forgetfulness drug, since memories are there for a purpose: to teach us the lessons of life. Even unpleasant memories, they said, serve some larger purpose. The drug got a thumbs-down from the President’s Council on Bioethics.
Its report concluded that “dulling our memory of terrible things [would] make us too comfortable with the world, unmoved by suffering, wrongdoing, or cruelty.… Can we become numb to life’s sharpest sorrows without also becoming numb to its greatest joys?”
Dr. David Magus of Stanford University’s Center for Biomedical Ethics says, “
Our breakups, our relationships, as painful as they are, we learn from some of those painful experiences. They make us better people.”
Others disagree. Dr. Roger Pitman of Harvard University says that if a doctor encounters an accident victim who is in intense pain, “
should we deprive them of morphine because we might be taking away the full emotional experience? Who would ever argue with that? Why should psychiatry be different? I think that somehow behind this argument lurks the notion that mental disorders are not the same as physical disorders.”
How this debate is ultimately resolved could have direct bearing on the next generation of drugs, since propranolol is not the only one involved.
In 2008, two independent groups, both working with animals, announced other drugs that could actually erase memories, not just manage the pain they cause. Dr. Joe Tsien of the Medical College of Georgia and his colleagues in Shanghai stated that they had actually eliminated a memory in mice using a protein called CaMKII, while scientists at SUNY Downstate Medical Center
in Brooklyn found that the molecule PKMzeta could also erase memories. Dr. Andre Fenson, one of the authors of this second study, said, “
If further work confirms this view, we can expect to one day see therapies based on PKMzeta memory erasure.” Not only may the drug erase painful memories, it also “might be useful in treating depression, general anxiety, phobias, post-traumatic stress, and addictions,” he added.
So far, research has been limited to animals, but human trials will begin soon. If the results transfer from animals to humans, then a forgetful pill may be a real possibility. It will not be the kind of pill seen in Hollywood movies (which conveniently creates amnesia at a precise, opportune time) but could have vast medical applications in the real world for people haunted by traumatic memories. It remains to be seen, though, how selective this memory erasure might be in humans.
WHAT CAN GO WRONG?
There may come a day, however, when we can carefully register
all
the signals passing through the hippocampus, thalamus, and the rest of the limbic system and make a faithful record. Then, by feeding this information into our brains, we might be able to reexperience the totality of what another person went through. Then the question is: What can go wrong?
In fact, the implications of this idea were explored in a movie,
Brainstorm
(1983), starring Natalie Wood, which was far ahead of its time. In the movie, scientists create the Hat, a helmet full of electrodes that can faithfully record all the sensations a person is experiencing. Later, a person can have precisely the same sensory experience by playing that tape back into his brain. For fun, one person puts on the Hat when he is making love and tape-records the experience. Then the tape is put into a loop so the experience is greatly magnified. But when another person unknowingly inserts the experience into his brain, he nearly dies because of a sensory overload. Later, one of the scientists experiences a fatal heart attack. But before she dies, she records her final moments on tape. When another person plays the death tape into his brain, he, too, has a sudden heart attack and dies.
When news of this powerful machine finally leaks out, the military wants to seize control. This sets off a power struggle between the military, which views it as a powerful weapon, and the original scientists, who want to use it to unlock the secrets of the mind.
Brainstorm
prophetically highlighted not only the promise of this technology but also its potential pitfalls. It was meant to be science fiction, but some scientists believe that sometime in the future, these very issues may play out in our headlines and in our courts.
Earlier, we saw that there have been promising developments in recording a single memory created by a mouse. It may take until mid-century before we can reliably record a variety of memories in primates and humans. But creating the Hat, which can record the totality of stimulation entering into the brain, requires tapping into the raw, sensory data surging up the spinal cord and into the thalamus. It may be late in this century before this can be done.
SOCIAL AND LEGAL ISSUES
Some aspects of this dilemma may play out in our lifetimes. On one hand, we may reach a point where we can learn calculus by simply uploading the skill. The educational system would be turned upside down; perhaps it would free teachers to spend more time mentoring students and giving them one-on-one attention in areas of cognition that are less skill-based and cannot be mastered by hitting a button. The rote memorization necessary to become a professional doctor, lawyer, or scientist could also be drastically reduced through this method.
In principle, it might even give us memories of vacations that never happened, prizes that we never won, lovers whom we never loved, or families that we never had. It could make up for deficiencies, creating perfect memories of a life never lived. Parents would love this, since they could teach their children lessons taken from real memories. The demand for such a device could be enormous. Some ethicists fear that these fake memories would be so vivid that we would prefer to relive imaginary lives rather than experiencing our real ones.
The unemployed may also benefit from being able to learn new marketable skills by having memories implanted. Historically, millions of workers were left behind every time a new technology was introduced, often without any safety net. That’s why we don’t have many blacksmiths or wagon makers anymore. They turned into autoworkers and other industrial workers. But retraining requires a large amount of time and commitment. If skills can be implanted into the brain, there would be an immediate impact on the world
economic system, since we wouldn’t have to waste so much human capital. (To some degree, the value of a certain skill may be devalued if memories can be uploaded into anyone, but this is compensated for by the fact that the number and quality of skilled workers would vastly increase.)
The tourism industry will also experience a tremendous boost. One barrier to foreign travel is the pain of learning new customs and conversing with new phrases. Tourists would be able to share in the experience of living in a foreign land, rather than getting bogged down trying to master the local currency and the details of the transportation system. (Although uploading an entire language, with tens of thousands of words and expressions, would be difficult, it might be possible to upload enough information to carry on a decent conversation.)
Inevitably, these memory tapes will find their way onto social media. In the future, you might be able to record a memory and upload it to the Internet for millions to feel and experience. Previously, we discussed a brain-net through which you can send thoughts. But if memories can be recorded and created, you might also be able to send entire experiences. If you just won a gold medal at the Olympic Games, why not share the agony and the ecstasy of victory by putting your memories on the web? Maybe the experience will go viral and billions can share in your moment’s glory. (Children, who are often at the forefront of video games and social media, may make a habit of recording memorable experiences and uploading them onto the Internet. Like taking a picture with a cell phone, it would be second nature to them to record entire memories. This would require both the sender and the receiver to have nearly invisible nanowires connecting to their hippocampus. The information would then be sent wirelessly to a server, which would convert the message to a digital signal that can be carried by the Internet. In this way, you could have blogs, message boards, social media, and chat rooms where, instead of uploading pictures and videos, you would upload memories and emotions.)
A LIBRARY OF SOULS
People may also want to have a geneology of memories. When searching records of our ancestors, we see only a one-dimensional portrait of their lives. Throughout human history, people have lived, loved, and died without
leaving a substantial record of their existence. Mostly we just find the birth and death dates of our relatives, with little in between. Today we leave a long trail of electronic documents (credit card receipts, bills, e-mails, bank statements, etc.). By default, the web is becoming a giant repository of all the documents that describe our lives, but this still doesn’t tell anyone much about what we were thinking or feeling. Perhaps in the far future, the web could become a giant library chronicling not just the details of our lives but also our consciousness.
In the future, people might routinely record their memories so their descendants can share the same experiences. Visiting the library of memories for your clan, you would be able to see
and
feel how they lived, and also how you fit into the larger scheme of things.
This means that anyone could replay our lives, long after we have died, by hitting the “play” button. If this vision is correct, it means that we might be able to “bring back” our ancestors for an afternoon chat, simply by inserting a disk into the library and pushing a button.
Meanwhile, if you want to share in the experiences of your favorite historical figures, you might be able to have an intimate look into how they felt as they confronted major crises in their lives. If you have a role model and wish to know how they negotiated and survived the great defeats of their life, you could experience their memory tapes and gain valuable insight. Imagine being able to share the memories of a Nobel Prize–winning scientist. You might get clues about how great discoveries are made. Or you might be able to share the memories of great politicians and statesmen as they made crucial decisions that affected world history.
Dr. Miguel Nicolelis believes all this will one day become reality. He says, “
Each of these perennial records would be revered as a uniquely precious jewel, one among billions of equally exclusive minds that once lived, loved, suffered, and prospered, until they, too, become immortalized, not clad in cold and silent gravestones, but released through vivid thoughts, intensely lived loves, and mutually endured sorrows.”