The Future of the Mind (8 page)

In short, there could be two wills acting within one skull, sometimes struggling for control of the body. This creates the bizarre situation where the left hand (controlled by the right brain) starts to behave independently of your wishes, as if it were an alien appendage.

There is one documented case in which a man was about to hug his wife with one hand, only to find that the other hand had an entirely different agenda. It delivered a right hook to her face. Another woman reported that she would pick out a dress with one hand, only to see her other hand grab an entirely different outfit. Meanwhile, one man had difficulty sleeping at night thinking that his other rebellious hand might strangle him.

At times, split-brain people think they are living in a cartoon, where one hand struggles to control the other. Physicians sometimes call this the Dr. Strangelove syndrome, because of a scene in the movie in which one hand has to fight against the other hand.

Dr. Sperry, after detailed studies of split-brain patients, finally concluded that there could be two distinct minds operating in a single brain. He wrote that each hemisphere is “
indeed a conscious system in its own right, perceiving, thinking, remembering, reasoning, willing, and emoting, all at a characteristically human level, and … both the left and right hemisphere may be conscious simultaneously in different, even in mutually conflicting, mental experiences that run along in parallel.”

When I interviewed Dr. Michael Gazzaniga of the University of California, Santa Barbara, an authority on split-brain patients,
I asked him how experiments can be done to test this theory. There are a variety of ways to communicate separately to each hemisphere without the knowledge of the other hemisphere. One can, for example, have the subject wear special glasses on which questions can be shown to each eye separately, so that directing questions to each hemisphere is easy. The hard part is trying to get an answer from each hemisphere. Since the right brain cannot speak (the speech centers are located only in the left brain), it is difficult to get answers from the right brain. Dr. Gazzaniga told me that to find out what the right brain was thinking, he created an experiment in which the (mute) right brain could “talk” by using Scrabble letters.

He began by asking the patient’s left brain what he would do after graduation. The patient replied that he wanted to become a draftsman. But things got interesting when the (mute) right brain was asked the same question. The right brain spelled out the words: “automobile racer.” Unknown to the dominant left brain, the right brain secretly had a completely different agenda for the future. The right brain literally had a mind of its own.

Rita Carter writes, “
The possible implications of this are mind-boggling. It suggests that we might all be carrying around in our skulls a mute prisoner with a personality, ambition, and self-awareness quite different from the day-to-day entity we believe ourselves to be.”

Perhaps there is truth to the oft-heard statement that “inside him, there is someone yearning to be free.” This means that the two hemispheres may even have different beliefs. For example, the neurologist V. S. Ramanchandran describes one split-brain patient who, when asked if he was a believer or not, said he was an atheist, but his right brain declared he was a believer. Apparently, it is possible to have two opposing religious beliefs residing in the same brain. Ramachandran continues: “
If that person dies, what happens? Does one hemisphere go to heaven and the other go to hell? I don’t know the answer to that.”

(It is conceivable, therefore, that a person with a split-brain personality might be both Republican and Democrat at the same time. If you ask him whom he will vote for, he will give you the candidate of the left brain, since the right brain cannot speak. But you can imagine the chaos in the voting booth when he has to pull the lever with one hand.)

WHO IS IN CHARGE?

One person who has spent considerable time and done much research to understand the problem of the subconscious mind is Dr. David Eagleman, a neuroscientist at the Baylor College of Medicine. When I interviewed him, I asked him, If most of our mental processes are subconscious, then why are we ignorant of this important fact? He gave an example of
a young king who inherits the throne and takes credit for everything in the kingdom, but hasn’t the slightest clue about the thousands of staff, soldiers, and peasants necessary to maintain the throne.

Our choice of politicians, marriage partners, friends, and future occupations
are all influenced by things that we are not conscious of. (For example, it is an odd result, he says, that “
people named Denise or Dennis are disproportionately likely to become dentists, while people named Laura or Lawrence are more likely to become lawyers, and people with names like George or Georgina to become geologists.”) This also means that what we consider to be “reality” is only an approximation that the brain makes to fill in the gaps. Each of us sees reality in a slightly different way. For example, he pointed out,
“at least 15 percent of human females possess a genetic mutation that gives them an extra (fourth) type of color photoreceptor—and this allows them to discriminate between colors that look identical to the majority of us with a mere three types of color photoreceptors.”

Clearly, the more we understand the mechanics of thought, the more questions arise. Precisely what happens in the command center of the mind when confronted with a rebellious shadow command center? What do we mean by “consciousness” anyway, if it can be split in half? And what is the relationship between consciousness and “self” and “self-awareness”?

If we can answer these difficult questions, then perhaps it will pave the way for understanding nonhuman consciousness, the consciousness of robots and aliens from outer space, for example, which may be entirely different from ours.

So let us now propose a clear answer to this deceptively complex question: What is consciousness?

The mind of man is capable of anything … because everything is in it, all the past as well as all the future.

—JOSEPH CONRAD

Consciousness can reduce even the most fastidious thinker to blabbering incoherence.

—COLIN MCGINN

2
CONSCIOUSNESS—A PHYSICIST’S VIEWPOINT

The idea of consciousness has intrigued philosophers for centuries, but it has resisted a simple definition, even to this day. The philosopher David Chalmers has cataloged more than twenty thousand papers written on the subject; nowhere in science have so many devoted so much to create so little consensus. The seventeenth-century thinker Gottfried Leibniz once wrote, “If you could blow the brain up to the size of a mill and walk about inside, you would not find consciousness.”

Some philosophers doubt that a theory of consciousness is even possible. They claim that consciousness can never be explained since an object can never understand itself, so we don’t even have the mental firepower to solve this perplexing question. Harvard psychologist Steven Pinker writes, “
We cannot see ultraviolet light. We cannot mentally rotate an object in the fourth dimension. And perhaps we cannot solve conundrums like free will and sentience.”

In fact, for most of the twentieth century, one of the dominant theories of psychology, behaviorism, denied the importance of consciousness entirely. Behaviorism is based on the idea that only the objective behavior of animals
and people is worthy of study, not the subjective, internal states of the mind.

Others have given up trying to define consciousness, and try simply to describe it. Psychiatrist Giulio Tononi has said, “
Everybody knows what consciousness is: it is what abandons you every night when you fall into dreamless sleep and returns the next morning when you wake up.”

Although the nature of consciousness has been debated for centuries, there has been little resolution. Given that physicists created many of the inventions that have made the explosive advancements in brain science possible, perhaps it will be useful to follow an example from physics in reexamining this ancient question.

HOW PHYSICISTS UNDERSTAND THE UNIVERSE

When a physicist tries to understand something, first he collects data and then he proposes a “model,” a simplified version of the object he is studying that captures its essential features. In physics, the model is described by a series of parameters (e.g., temperature, energy, time). Then the physicist uses the model to predict its future evolution by simulating its motions. In fact, some of the world’s largest supercomputers are used to simulate the evolution of models, which can describe protons, nuclear explosions, weather patterns, the big bang, and the center of black holes. Then you create a better model, using more sophisticated parameters, and simulate it in time as well.

For example, when Isaac Newton was puzzling over the motion of the moon, he created a simple model that would eventually change the course of human history: he envisioned throwing an apple in the air. The faster you threw the apple, he reasoned, the farther it would travel. If you threw it fast enough, in fact, it would encircle the Earth entirely, and might even return to its original point. Then, Newton claimed, this model represented the path of the moon, so the forces that guided the motion of the apple circling the Earth were identical to the forces guiding the moon.

But the model, by itself, was still useless. The key breakthrough came when Newton was able to use his new theory to simulate the future, to calculate the future position of moving objects. This was a difficult problem, requiring him to create an entirely new branch of mathematics, called calculus. Using this new mathematics, Newton was then able to predict the trajectory of not just the moon, but also Halley’s Comet and the planets.
Since then, scientists have used Newton’s laws to simulate the future path of moving objects, from cannonballs, machines, automobiles, and rockets to asteroids and meteors, and even stars and galaxies.

The success or failure of a model depends on how faithfully it reproduces the basic parameters of the original. In this case, the basic parameter was the location of the apple and the moon in space and time. By allowing this parameter to evolve (i.e., letting time move forward), Newton unlocked, for the first time in history, the action of moving bodies, which is one of the most important discoveries in science.

Models are useful, until they are replaced by even more accurate models described by better parameters. Einstein replaced Newton’s picture of forces acting on apples and moons with a new model based on a new parameter, the curvature of space and time. An apple moved not because the Earth exerted a force on it, but because the fabric of space and time was stretched by the Earth, so the apple was simply moving along the surface of a curved space-time. From this, Einstein could then simulate the future of the entire universe. Now, with computers, we can run simulations of this model into the future and create gorgeous pictures presenting the collisions of black holes.

Let us now incorporate this basic strategy into a new theory of consciousness.

DEFINITION OF CONSCIOUSNESS

I’ve taken bits and pieces from previous descriptions of consciousness in the fields of neurology and biology in order to define consciousness as follows:

Consciousness is the process of creating a model of the world using multiple feedback loops in various parameters (e.g., in temperature, space, time, and in relation to others), in order to accomplish a goal (e.g., find mates, food, shelter)
.

I call this the “space-time theory of consciousness,” because it emphasizes the idea that animals create a model of the world mainly in relation to space, and to one another, while humans go beyond and create a model of the world in relation to time, both forward and backward.

For example, the lowest level of consciousness is Level 0, where an organism
is stationary or has limited mobility and creates a model of its place using feedback loops in a few parameters (e.g., temperature). For example, the simplest level of consciousness is a thermostat. It automatically turns on an air conditioner or heater to adjust the temperature in a room, without any help. The key is a feedback loop that turns on a switch if the temperature gets too hot or cold. (For example, metals expand when heated, so a thermostat can turn on a switch if a metal strip expands beyond a certain point.)

Each feedback loop registers “one unit of consciousness,” so a thermostat would have a single unit of Level 0 consciousness, that is, Level 0:1.

In this way, we can rank consciousness numerically, on the basis of the number and complexity of the feedback loops used to create a model of the world. Consciousness is then no longer a vague collection of undefined, circular concepts, but a system of hierarchies that can be ranked numerically. For example, a bacterium or a flower has many more feedback loops, so they would have a higher level of Level 0 consciousness. A flower with ten feedback loops (which measure temperature, moisture, sunlight, gravity, etc.), would have a Level 0:10 consciousness.

Organisms that are mobile and have a central nervous system have Level I consciousness, which includes a new set of parameters to measure their changing location. One example of Level I consciousness would be reptiles. They have so many feedback loops that they developed a central nervous system to handle them. The reptilian brain would have perhaps one hundred or more feedback loops (governing their sense of smell, balance, touch, sound, sight, blood pressure, etc., and each of these contains more feedback loops). For example, eyesight alone involves a large number of feedback loops, since the eye can recognize color, movement, shapes, light intensity, and shadows. Similarly, the reptile’s other senses, such as hearing and taste, require additional feedback loops. The totality of these numerous feedback loops creates a mental picture of where the reptile is located in the world, and where other animals (e.g., prey) are located as well. Level I consciousness, in turn, is governed mainly by the reptilian brain, located in the back and center of the human head.