THE BRAIN #7
by David Eagleman
WHO WILL WE BE?
The human body is a masterpiece of complexity and beauty - a symphony of forty trillion cells working in concert However, it has its limitations. Your senses set boundaries on what you can experience. Your body sets limits on what you can do. But what if the brain could understand new kinds of inputs and control new kinds of limbs - expanding the reality we inhabit? We're at a moment in human history when the marriage of our biology and our technology will transcend the brain's limitations. We can hack our own hardware to steer a course into the future. This is poised to fundamentally change what it will mean to be a human.
Over the last 100,000 years our species has been on quite a journey: we've gone from living as primitive hunter-gatherers surviving on scraps to a planet-conquering hyper-connected species that defines its own destiny. Today we enjoy mundane experiences that our ancestors could never have dreamed of. We have clean rivers that we can call into our well-adorned caves when we desire. We hold small rock-sized devices that contain the knowledge of the world. We regularly see the tops of clouds and the curvature of our home planet from space. We send messages to the other side of the globe in eighty milliseconds and upload files to a floating space colony of humans at sixty megabits per second. Even when simply driving to work, we routinely move at speeds that outstrip biology's great masterpieces, such as cheetahs. Our species owes its runaway success to the special properties of the three pounds of matter stored inside our skulls.
What is it about the human brain that has made this journey possible? If we can understand the secrets behind our achievements, then perhaps we can direct the brain's strengths in careful, purposeful ways, opening a new chapter in the human story. What do the next thousand years have in store for us? In the far future, what will the human race be like?
A flexible, computational device
The secret to understanding our success - and our future opportunity - is the brain's tremendous ability to adjust, known as brain plasticity. As we saw in Chapter 2, this feature has allowed us to drop into any environment and pick up on the local details we need to survive, including the local language, local environmental pressures, or local cultural requirements.
Brain plasticity is also the key to our future, because it opens the door to making modifications to our own hardware. Let's begin by understanding just how flexible a computational device the brain is.
Consider the case of a young girl named Cameron Mott. At the age of four she began to have violent seizures. The seizures were aggressive: Cameron would suddenly drop to the floor, requiring her to wear a helmet all the time. She was quickly diagnosed with a rare and debilitating disease called Rasmussen's Encephalitis. Her neurologists knew that this form of epilepsy would lead to paralysis and eventually to death - and so they proposed a drastic surgery. In 2007, in an operation that took almost twelve hours, a team of neurosurgeons removed an entire half of Cameron's brain.
In this scan of Cameron's brain, the blank space is where half of her brain has been removed.
What would be the long-term effects of removing half her brain? As it turns out, the consequences were surprisingly slight. Cameron is weak on one side of her body, but otherwise she's essentially indistinguishable from the other children in her class. She has no problems understanding language, music, math, stories. She's good in school and she participates in sports.
How could this be possible? It's not that one half of Cameron's brain was simply not needed; instead, the remaining half of Cameron's brain dynamically rewired to take over the missing functions, essentially cramming all the operations into half the brain space. Cameron's recovery underscores a remarkable ability of the brain: it rewires itself to adjust to the inputs, outputs, and tasks at hand.
In this critical way, the brain is fundamentally unlike the hardware in our digital computers. Instead, it's "liveware". It reconfigures its own circuitry. Although the adult brain isn't quite as flexible as a child's, it still retains an astonishing ability to adapt and change. As we saw in previous chapters, every time we learn something new, whether it's the map of London or the ability to stack cups, the brain changes itself. It's this property of the brain - its plasticity - that enables a new marriage between our technology and our biology.
Plugging in peripheral devices
We've become progressively better at plugging machinery directly into our bodies. You may not realize it, but currently hundreds of thousands of people are walking around with artificial hearing and artificial vision.
With a device called a cochlear implant, an external microphone digitizes a sound signal and feeds it to the auditory nerve. Similarly, the retinal implant digitizes a signal from a camera, and sends it through an electrode grid plugged into the optic nerve at the back of the eye. For deaf and blind people around the planet, these devices have restored their senses.
It wasn't always clear that such an approach would work. When these technologies were first introduced, many researchers were skeptical: the brain is wired up with such precision and specificity that it wasn't clear there could be a meaningful dialog between metal electrodes and biological cells. Would the brain be able to understand crude, non-biological signals, or would it be confused by them?
As it turns out, the brain learns to interpret the signals. Getting used to these implants is a bit like learning a new language for the brain. At first the foreign electrical signals are unintelligible, but the neural networks eventually extract patterns in incoming data.
ARTIFICIAL HEARING AND VISION
A cochlear implant bypasses problems in the biology of the ear and feeds its audio signals directly to the undamaged auditory nerve, the brain's data cable for sending electrical impulses on to the auditory cortex for decoding. The implant picks up sounds from the outside world and passes them to the auditory nerve by means of sixteen tiny electrodes. The experience of hearing doesn't arrive immediately: people have to learn to interpret the foreign dialect of the signals fed to the brain. As one cochlear implant recipient, Michael Chorost, describes his experience:
"When the device was turned on a month after surgery, the first sentence I heard sounded like'Zzzzzz szz szvizzz ur brfzzzzzz?' My brain gradually learned how to interpret the alien signal. Before long, 'Zzzzzz szz szvizzz ur brfzzzzzz?' became 'What did you have for breakfast?' After months of practice, I could use the telephone again, even converse in loud bars and cafeterias."
Retinal implants work on similar principles. The tiny electrodes of the retinal implant bypass the normal functions of the photoreceptor sheet, sending out their tiny sparks of electrical activity. These implants are used mostly for eye diseases in which the photoreceptors at the back of the eye are degenerating, but in which the cells of the optic nerve remain healthy. Even though the signals sent by the implant are not precisely what the visual system is used to, the downstream processes are able to learn to extract the information they need for vision.
Although the input signals are crude, the brain finds a way to make sense of them. It hunts for patterns, cross-referencing with other senses. If there's structure to be found in the incoming data, the brain ferrets it out - and after several weeks the information begins to take on meaning. Even though the implants give slightly different signals than do our natural sense organs, the brain figures out how to make do with the information it can get.
Plug and play: an extrasensory future
The brains plasticity allows new inputs to be interpreted. What sensory opportunities does that open up?
We come into the world with a standard set of basic senses: hearing, touch, sight, smell, and taste, along with other senses such as balance, vibration, and temperature. The sensors we have are the portals by which we pick up signals from our environment.
However, as we saw in the first chapter, these senses only allow us to experience a tiny fraction of the world around us. All the information sources for which we don't have sensors are invisible to us.
I think of our sensory portals as peripheral plug-and-play devices. The key is that the brain doesn't know and doesn't care where it gets the data. Whatever information comes in, the brain figures out what to do with it. In this framework, I think of the brain as a general-purpose computing device: it operates on whatever it's fed. The idea is that Mother Nature only needed to invent the principles of brain operation once - and then she was freed up to tinker with designing new input channels.
The end result is that all these sensors we know and love are merely devices that can be swapped in and out. Stick them in and the brain can get to work. In this framework, evolution doesn't need to continually redesign the brain, just the peripherals, and the brain figures out how to utilize them.
Just look across the animal kingdom, and you'll find a mind-boggling variety of peripheral sensors in use by animal brains. Snakes have heat sensors. The glass knifefish has electrosensors for interpreting changes in the local electrical field. Cows and birds have magnetite, with which they can orient themselves to the Earth's magnetic field. Animals can see in ultraviolet; elephants can hear at very long distances, while dogs experience a richly scented reality. The crucible of natural selection is the ultimate hacker space, and these are just some of the ways that genes have figured out how to channel data from the outside world into the internal world. The end result is that evolution has built a brain that can experience many different slices of reality.
The consequence I want to highlight is that there may be nothing special or fundamental about the sensors we're used to. They're just what we've inherited from a complex history of evolutionary constraints. We're not stuck with them.
Our main proof of principle for this idea comes from a concept called sensory substitution, which refers to feeding sensory information through unusual sensory channels such as vision through touch. The brain figures out what to do with the information, because it doesn't care how the data finds its way in.
Sensory substitution might sound like science fiction, but in fact it's already well established. The first demonstration was published in the journal Nature in 1969. In that report, neuroscientist Paul Bach-y-Rita demonstrated that blind subjects could learn to "see" objects - even when the visual information was fed to them in an unusual way. Blind people were seated in a modified dental chair, and the video feed from a camera was converted into a pattern of small plungers pressed against their lower back. In other words, if you put a circle in front of the camera, the participant would feel a circle on her back. Put a face in front of the camera, and the participant feels the face on her back. Amazingly, blind people could come to interpret the objects, and could also experience the increasing size of approaching objects. They could, at least in a sense, come to see through their backs.
This was the first example of sensory substitution of many to follow. Modern incarnations of this approach include turning a video feed into a sound stream, or a series of small shocks on the forehead or the tongue.
Four methods to push visual information to the brain through unusual sensory channels: the lower back, the ears, the forehead, and the tongue.
An example of the latter is the postage stamp-sized device called the BrainPort, which works by delivering tiny electrical shocks to the tongue via a small grid that sits on the tongue. A blind subject wears sunglasses with a small camera attached. Camera pixels are converted into electrical pulses on the tongue, which feels something like the fizz of a carbonated drink. Blind people can become quite good at using the BrainPort, navigating obstacle courses or throwing a ball into a basket. One blind athlete, Erik Weihenmayer, uses the BrainPort to rock climb, assessing the position of crags and crevices from the patterns on his tongue.
If it sounds crazy to "see" through your tongue, just keep in mind that seeing is never anything but electrical signals streaming into the darkness of your skull. Normally this happens via the optic nerves, but there's no reason the information can't stream in via other nerves instead. As sensory substitution demonstrates, the brain takes whatever data comes in and figures out what it can make of it.
One of the projects in my laboratory is to build a platform for enabling sensory substitution. Specifically, we have built a wearable technology called the Variable Extra-Sensory Transducer, or VEST. Worn inconspicuously under the clothing, the VEST is covered with tiny vibratory motors. These motors convert data streams into dynamic patterns of vibration across the torso. We're using the VEST to give hearing to the deaf.
After about five days of using the VEST, a person who was born deaf can correctly identify spoken words. Although the experiments axe still in their early stages, we expect that after several months of wearing the VEST, users will come to have a direct perceptual experience - essentially the equivalent of hearing.
It may seem strange that a person can come to hear via moving patterns of vibration on the torso. But just as with the dental chair or the tongue grid, the trick is this: the brain doesn't care how it gets the information, as long as it gets it.
Sensory substitution is great for circumventing broken sensory systems - but beyond substitution, what if we could use this technology to extend our sensory inventory? To this end, my students and I are currently adding new senses to the human repertoire to augment our experience of the world.
Consider this: the internet is streaming petabytes of interesting data, but currently we can only access that information by staring at a phone or computer screen. What if you could have real-time data streamed into your body, so that it became part of your direct experience of the world? In other words, what if you could feel data? This could be weather data, stock exchange data, Twitter data, cockpit.
To provide sensory substitution for the deaf, my graduate student Scott Novich and I built the VEST. This wearable tech captures sound from the environment and maps it to small vibrational motors all over the torso. The motors activate in patterns according to the frequencies of the sound. In this way, sound becomes moving patterns of vibrations.
At first, these vibratory signals make no sense. But with enough practice, the brain works out what to do with the data. Deaf people become able to translate the complicated patterns on the torso into an understanding of what's being said.The brain figures out how to unconsciously unlock the patterns, similar to the manner in which a blind person comes to effortlessly read Braille.
The VEST has the potential to be a game-changer for the deaf community. Unlike a cochlear implant, it doesn't require an invasive surgery. And it's at least twenty times cheaper, which makes it a solution that can be global.
The bigger vision for the VEST is this: beyond sound, it can also serve as a platform for any kind of streaming information to find its way to the brain.
data from an airplane, or data about the state of a factory - all encoded as a new vibratory language that the brain learns to understand. As you went about your daily tasks, you could have a direct perception of whether its raining a hundred miles away or whether it's going to snow tomorrow. Or you could develop intuitions about where the stock markets were going, subconsciously identifying the movements of the global economy. Or you could sense what's trending across the Twittersphere, and in this way be tapped into the consciousness of the species.
Although this sounds like science fiction, we're not far off from this future - all thanks to the brain's talent at extracting patterns, even when we're not trying. That is the trick that can allow us to absorb complex data and incorporate it into our sensory experience of the world. Like reading this page, absorbing new data streams will come to feel effortless. Unlike reading, however, sensory addition would be a way to take on new information about the world without having to consciously attend to it.
At the moment, we don't know the limits - or if there are limits -to the kinds of data the brain can incorporate. But it's clear that we are no longer a natural species that has to wait for sensory adaptations on an evolutionary timescale. As we move into the future, we will increasingly design our own sensory portals on the world. We will wire ourselves into an expanded sensory reality.
How to get a better body
How we sense the world is only half the story. The other half is how we interact with it. In the same way that we are beginning to modify our sensory selves, can the brain's flexibility be leveraged to modify the way we reach out and touch the world?
Meet Jan Scheuermann. Because of a rare genetic disease called spinocerebellar disorder, the spinal cord nerves connecting her brain to her muscles have deteriorated. She can feel her body, but she can't move it. As she describes it, "my brain is saying lift up' to my arm, but the arm is saying 'I can't hear you.'" Her total paralysis made her an ideal candidate for a new study at the University of Pittsburgh School of Medicine.
Researchers there have implanted two electrodes into her left motor cortex, the last stop for brain signals before they plunge down the spinal cord to control the muscles of the arm. The electrical storms in her cortex are monitored, translated on a computer to understand the intention, and the output is used to control the world's most advanced robotic arm.
The electrical signals in Jan's brain are decoded, and the bionic arm follows the commands. Via her thoughts, the arm can accurately reach, the fingers can smoothly curl and uncurl, and the wrist can roll and flex.
When Jan wants to move the robotic arm, she simply thinks about moving it. As she moves the arm, Jan tends to talk to it in the third person: "Go up. Go down, down, down. Go right. And grasp. Release." And the arm does so on cue. Although she speaks the commands out loud, she has no need to. There's a direct physical link between her brain and the arm. Jan reports that her brain has not forgotten how to move an arm, even though it hadn't moved one in ten years. "It's like riding a bicycle," she says.
Jan's proficiency points to a future in which we use technology to enhance and extend our bodies, not only replacing limbs or organs, but improving them: elevating them from human fragility to something more durable. Her robotic arm is just the first hint of an upcoming bionic era in which we'll be able to control much stronger and longer-lasting equipment than the skin and muscle and brittle bones we're born with. Among other things, that opens up new possibilities for space travel, something for which our delicate bodies are ill-equipped.
Beyond replacement limbs, advancing brain-machine interface technology suggests more exotic possibilities. Imagine extending your body to be something unrecognizable. Start with this idea: what if you could use your brain signals to wirelessly control a machine across the room? Envision answering emails while simultaneously using your motor cortex to control a thought-controlled vacuum cleaner. At first glance, the concept may sound unworkable, but keep in mind that brains are great at running tasks in the background, not requiring much in the way of conscious bandwidth. Just consider how easily you can drive a car while simultaneously talking to a passenger and fiddling with the radio knob.
With the proper brain-machine interface and wireless technology, there's no reason you couldn't control large devices such as a crane or a forklift wirelessly, at a distance, with your thoughts, in the same way that you might absent-mindedly dig with a trowel or play a guitar. Your capacity to do this well would be enhanced by sensory feedback, which could be done visually (you watch how the machine moves), or even by feeding data back into your somatosensory cortex (you feel how the machine moves). Controlling such limbs would take practice and be awkward at first, in the same way that a baby has to flail for some months to learn how to finely control its arms and legs. With time, these machines would effectively become an extra limb - one that could have extraordinary strength, hydraulic or otherwise. They would come to feel the way that your arms or legs do to you now. They would just be another limb - simple extensions of ourselves.
We don't know of a theoretical limit on the kinds of signals brain could learn to incorporate. It may be possible to have almost any sort of physical body and any kind of interaction with the world that we want. There's no reason an extension of you couldn't be taking care of tasks on the other side of the planet, or mining rocks on the moon while you're enjoying a sandwich here on Earth.
The body we arrive with is really just the starting point for humanity. In the distant future, we won't just be extending our physical bodies, but fundamentally our sense of self. As we take on new sensory experiences and control new kinds of bodies, that will change us profoundly as individuals: our physicality sets the stage for how we feel, how we think, and who we are. Without the limitations of the standard-issue senses and the standard-issue body, we'll become different people. Our great-great-great-great-grandchildren may struggle to understand who we were, and what was important to us. At this moment in history, we may have more in common with our Stone Age ancestors than with our near-future descendants.
Stay in' alive
We're already beginning to extend the human body, but no matter how much we enhance ourselves, there is one snag that's difficult to avoid: our brains and bodies are built of physical stuff. They will deteriorate and die. There will come a moment when all your neural activity will come to a halt, and then the glorious experience of being conscious will come to an end. It doesn't matter who you know or what you do: this is the fate of all of us. In fact, it's the fate of all life, but only humans are so unusually foresighted that we suffer over this knowledge.
Not everyone is content to suffer; some have chosen to fight death's specter. Scattered confederacies of researchers are interested in the idea that a better understanding of our biology can address our mortality. What if in the future we didn't have to die?
When my friend and mentor, Francis Crick, was cremated, I spent some time thinking about what a shame it was that all his neural matter was going up in flames. That brain contained all the knowledge, wisdom, and intellect of one of the heavyweight champions of twentieth-century biology. All the archives of his life - his memories, his capacity for insight, his sense of humor - were stored in the physical structure of his brain, and simply because his heart had stopped everyone was content to throw away the hard-drive. It made me wonder: could the information in his brain be preserved somehow? If the brain were preserved, could a person's thoughts and awareness and personhood ever be brought back to life?
For the past fifty years, the Alcor Life Extension Foundation has been developing technology they believe will allow people living today to enjoy a second life-cycle later. The organization currently stores 129 people in a deep freeze that halts their biological decay.
Here's how cryopreservation works: first, an interested party signs his life insurance policy over to the foundation. Then, upon the legal declaration of his death, Alcor is alerted. A local team sweeps in to manage the body.
The team immediately transfers the body to an ice bath. In a process known as cryoprotective perfusion, they circulate sixteen different chemicals to protect the cells as the body cools. The body is then relocated as quickly as possible to the Alcor operating room for the final stage of the procedure. The body is cooled by computer-controlled fans circulating extremely low-temperature nitrogen gas. The goal is to cool all parts of the body below -124°C as rapidly as possible to avoid any ice formation. The process takes about three hours, at the end of which the body will have "vitrified", that is, reached a stable ice-free state. The body is then further cooled to -196°C over the next two weeks.
LEGAL VERSUS BIOLOGICAL DEATH
A person is declared legally dead when either his brain is clinically dead or his body has experienced irreversible cessation of respiration and circulation. For the brain to be declared dead, all activity must have ceased in the cortex, involved in higher function. After brain death, vital functions can still be maintained for organ donation or body donation, a fact critical for Alcor. Biological death, on the other hand, happens in the absence of intervention, and involves the death of cells throughout the body: in the organs and in the brain, and means that the organs are no longer suitable for donation. Without oxygen from circulating blood, the body's cells rapidly start to die.To preserve a body and a brain in its least degraded form, cell death must be stopped, or at least decelerated, as quickly as possible. In addition, during cooling the priority is to prevent ice crystals from forming, which can destroy the delicate structures of the cells.
Not all clients choose to have their whole body frozen. A less expensive option is to simply preserve the head. The separation of the head from the body is performed on a surgical table, where the blood and fluids are washed out and, as with the whole-body clients, are replaced with liquids that fix the tissue into place.
At the end of the procedure, the clients are lowered into ultra-cooled liquid in giant stainless steel cylinders called dewars. This is where they'll remain for a long time; no one on the planet today knows how to successfully unfreeze and reanimate these frozen residents. But that's not the point. The hope is that one day the technology will exist to carefully thaw - and then revive - the people in this community. Civilizations in the distant future, it is presumed, will command the technology to cure the diseases that ravaged these bodies and brought them to a halt.
Alcor members understand that the technology may never exist to revive them. Each person dwelling in the Alcor dewars took a leap of faith, hoping and dreaming that someday the technology will materialize to thaw them out, revive them, and give them a second chance at life. The venture is a gamble that the future will develop the necessary technology. I spoke to a member of the community (who awaits his eventual entry into the dewars when the time comes), and he allowed the whole conception was a wager. But, he pointed out, at least it gives him a better-than-zero chance of cheating death - better odds than the rest of us.
Dr. Max More, who runs the facility, doesn't use the word "immortality". Instead, he says, Alcor is about giving people a second chance at life, with the potential to live thousands of years or longer. Until that time comes, Alcor is their final resting place.
HUMANS WILL NOT FIND THE WAY TO LIVE FOR THOUSANDS OF YEARS. GOD DOES SAY PEOPLE WILL LIVE LIKE TREES IN LONGEVITY IN THE COMING NEW AGE. SO WE ARE FINDING MORE AND MORE ABOUT THE BRAIN EVERY YEAR; YOU HAVE BEEN READING SOME OF THE LATEST [UP TO 2015] THAT SCIENCE IS FINDING ON THE BRAIN; TO BE SURE THERE WILL BE MUCH MORE DISCOVERED IN THE YEARS TO COME. MANY OF THESE THINGS WILL BE OF ENORMOUS HELP FOR THOSE WITH DEBILITATING PHYSICAL FUNCTIONS OF THE BODY.
WE HAVE SEEN WITH THE RECENT MOVIE STARING WILL SMITH, THE FACTS ABOUT “CONCUSSIONS” - THE HEAD BEING BANGED MANY MANY TIMES IN SOME CONTACT TEAM SPORTS, LIKE RUGBY AND AMERICAN FOOTBALL, ICE HOCKEY, AND EVEN SOCCER. WHEN I PLAYED SOCCER THROUGH MY TEENAGE YEARS, THE RULES OR I SHOULD SAY NOT BREAKING THE RULES, WAS VERY MUCH IN VOGE, TODAY IT IS A WAY MORE BRUTAL GAME, A WIN AT ALL COST ATTITUDE.
THE RULES FOR MANY OF THE TEAM SPORTS REALLY DO NEED TO BE CHANGED. THE WAY SOME OF THESE SPORTS ARE PLAYED TODAY, MOST CERTAINLY WILL NOT BE PLAYED THAT WAY IN THE AGE TO COME.
THE BRAIN IS A FANTASTIC PART OF THE HUMAN BODY, IT SHOULD BE RESPECTED DEEPLY, TAKEN CARE OF WITH ALL THE HEALTH RULES FOLLOWED: GOOD CORRECT DIET, ENOUGH SLEEP [7-9 HOURS EACH DAY], AND VARIOUS WAYS TO KEEP IT MENTALLY EXERCISED.