The Future of the Mind Page 7

  This works for mice as well. Put an electrode in front of a piece of cheese. If the mouse gets too close, the electrode will shock it. One feedback loop tells the mouse to eat the cheese, but another one tells the mouse to stay away and avoid being shocked. By adjusting the location of the electrode, you can get the mouse to oscillate, torn between two conflicting feedback loops. While a human has a CEO in its brain to evaluate the pros and cons of the situation, the mouse, governed by two conflicting feedback loops, goes back and forth. (This is like the proverb about the donkey that starves to death because it is placed between two equal bales of hay.)

  Precisely how does the brain simulate the future? The human brain is flooded by a large amount of sensory and emotional data. But the key is to simulate the future by making causal links between events—that is, if A happens, then B happens. But if B happens, then C and D might result. This sets off a chain reaction of events, eventually creating a tree of possible cascading futures with many branches. The CEO in the prefrontal cortex evaluates the results of these causal trees in order to make the ultimate decision.

  Let’s say you want to rob a bank. How many realistic simulations of this event can you make? To do this, you have to think of the various causal links involving the police, bystanders, alarm systems, relations with fellow criminals, traffic conditions, the DA’s office, etc. For a successful simulation of the robbery, hundreds of causal links may have to be evaluated.

  It is also possible to measure this level of consciousness numerically. Let’s say that a person is given a series of different situations like the one above and is asked to simulate the future of each. The sum total number of causal links that the person can make for all these situations can be tabulated. (One complication is that there are an unlimited number of causal links that a person might make for a variety of conceivable situations. To get around this complication, we divide this number by the average number of causal links obtained from a large control group. Like the IQ exam, one may multiply this number by 100. So a person’s level of consciousness, for example, might be Level III:100, meaning that the person can simulate future events just like the average person.)

  We summarize these levels of consciousness in the following diagram:

  LEVELS OF CONSCIOUSNESS FOR DIFFERENT SPECIES

  Space-time theory of consciousness. We define consciousness as the process of creating a model of the world using multiple feedback loops in various parameters (e.g., in space, time, and in relation to others), in order to accomplish a goal. Human consciousness is a particular type that involves mediating between these feedback loops by simulating the future and evaluating the past.

  (Notice that these categories correspond to the rough evolutionary levels we find in nature—e.g., reptiles, mammals, and humans. However, there are also gray areas, such as animals that might possess tiny aspects of different levels of consciousness, animals that do some rudimentary planning, or even single cells that communicate with one another. This chart is meant only to give you the larger, global picture of how consciousness is organized across the animal kingdom.)

  WHAT IS HUMOR? WHY DO WE HAVE EMOTIONS?

  All theories have to be falsifiable. The challenge for the space-time theory of consciousness is to explain all aspects of human consciousness in this framework. It can be falsified if there are patterns of thought that cannot be brought into this theory. A critic might say that surely our sense of humor is so quixotic and ephemeral that it is beyond explanation. We spend a great deal of time laughing with our friends or at comedians, yet it seems that humor has nothing to do with our simulations of the future. But consider this. Much of humor, such as telling a joke, depends on the punch line.

  When hearing a joke, we can’t help but simulate the future and complete the story ourselves (even if we’re unaware that we’re doing so). We know enough about the physical and social world that we can anticipate the ending, so we burst out with laughter when the punch line gives us a totally unexpected conclusion. The essence of humor is when our simulation of the future is suddenly disrupted in surprising ways. (This was historically important for our evolution since success depends, in part, on our ability to simulate future events. Since life in the jungle is full of unanticipated events, anyone who can foresee unexpected outcomes has a better chance at survival. In this way, having a well-developed sense of humor is actually one indication of our Level III consciousness and intelligence; that is, the ability to simulate the future.)

  For example, W. C. Fields was once asked a question about social activities for youth. He was asked, “Do you believe in clubs for young people?” He replied, “Only when kindness fails.”

  The joke has a punch line only because we mentally simulate a future in which children have social clubs, while W. C. Fields simulates a different future involving clubs as a weapon. (Of course, if a joke is deconstructed, it loses its power, since we have already simulated various possible futures in our minds.)

  This also explains what every comedian knows: timing is the key to humor. If the punch line is delivered too quickly, then the brain hasn’t had time to simulate the future, so there is no experience of the unanticipated. If the punch line is delivered too late, the brain has already had time to simulate various possible futures, so again the punch line loses the element of surprise.

  (Humor has other functions, of course, such as bonding with fellow members of our tribe. In fact, we use our sense of humor as a way to size up the character of others. This, in turn, is essential to determine our status within society. So in addition, laughter helps define our position in the social world, i.e., Level II consciousness.)

  WHY DO WE GOSSIP AND PLAY?

  Even seemingly trivial activities, such as engaging in idle gossip or horsing around with our friends, must be explained in this framework. (If a Martian were to visit a supermarket checkout line and view the huge display of gossip magazines, it might conclude that gossip is the main activity of humans. This observation would not be far off.)

  Gossiping is essential for survival because the complex mechanics of social interactions are constantly changing, so we have to make sense of this ever-shifting social terrain. This is Level II consciousness at work. But once we hear a piece of gossip, we immediately run simulations to determine how this will affect our own standing in the community, which moves us to Level III consciousness. Thousands of years ago, in fact, gossip was the only way to obtain vital information about the tribe. One’s very life often depended on knowing the latest gossip.

  Something as superfluous as “play” is also an essential feature of consciousness. If you ask children why they like to play, they will say, “Because it’s fun.” But that invites the next question: What is fun? Actually, when children play, they are often trying to reenact complex human interactions in simplified form. Human society is extremely sophisticated, much too involved for the developing brains of young children, so children run simplified simulations of adult society, playing games such as doctor, cops and robber, and school. Each game is a model that allows children to experiment with a small segment of adult behavior and then run simulations into the future. (Similarly, when adults engage in play, such as a game of poker, the brain constantly creates a model of what cards the various players possess, and then projects that model into the future, using previous data about people’s personality, ability to bluff, etc. The key to games like chess, cards, and gambling is the ability to simulate the future. Animals, which live largely in the present, are not as good at games as humans are, especially if they involve planning. Infant mammals do engage in a form of play, but this is more for exercise, testing one another, practicing future battles, and establishing the coming social pecking order rather than simulating the future.)

  My space-time theory of consciousness might also shed light on another controversial topic: intelligence. Although IQ exams claim to measure “intelligence,” IQ exams actually give no definition of intelligence in the first place. In fact, a cynic may
claim, with some justification, that IQ is a measure of “how well you do on IQ exams,” which is circular. In addition, IQ exams have been criticized for being too culturally biased. In this new framework, however, intelligence may be viewed as the complexity of our simulations of the future. Hence, a master criminal, who may be a dropout and functionally illiterate and score dismally low on an IQ exam, may also far outstrip the ability of the police. Outwitting the cops may entail simply being able to run more sophisticated simulations of the future.

  LEVEL I: STREAM OF CONSCIOUSNESS

  Humans are probably alone on this planet in being able to operate on all levels of consciousness. Using MRI scans, we can break down the different structures involved in each level of consciousness.

  For us, Level I stream of consciousness is largely the interplay between the prefrontal cortex and the thalamus. When taking a leisurely stroll in the park, we are aware of the smells of the plants, the sensation of a gentle breeze, the visual stimuli from the sun, and so on. Our senses send signals to the spinal cord, the brain stem, and then to the thalamus, which operates like a relay station, sorting out the stimuli and sending them on to the various cortices of the brain. The images of the park, for example, are sent to the occipital cortex in the back of the brain, while the sense of touch from the wind is sent to the parietal lobe. The signals are processed in appropriate cortices, and then sent to the prefrontal cortex, where we finally become conscious of all these sensations.

  This is illustrated in Figure 7.

  LEVEL II: FINDING OUR PLACE IN SOCIETY

  While Level I consciousness uses sensations to create a model of our physical location in space, Level II consciousness creates a model of our place in society.

  Let’s say we are going to an important cocktail party, in which people essential to our job will be present. As we scan the room, trying to identify people from our workplace, there is an intense interplay between the hippocampus (which processes memories), the amygdala (which processes emotions), and the prefrontal cortex (which puts all this information together).

  Figure 7. In Level I consciousness, sensory information travels through the brain stem, past the thalamus, onto the various cortices of the brain, and finally to the prefrontal cortex. Thus this stream of Level I consciousness is created by the flow of information from the thalamus to the prefrontal cortex. (illustration credit 2.1)

  With each image, the brain automatically attaches an emotion, such as happiness, fear, anger, or jealousy, and processes the emotion in the amygdala.

  If you spot your chief rival, whom you suspect of stabbing you in the back, the emotion of fear is processed by the amygdala, which sends an urgent message to the prefrontal cortex, alerting it to possible danger. At the same time, signals are sent to your endocrine system to start pumping adrenaline and other hormones into the blood, thereby increasing your heartbeat and preparing you for a possible fight-or-flight response.

  This is illustrated in Figure 8.

  But beyond simply recognizing other people, the brain has the uncanny ability to guess what other people are thinking about. This is called the Theory of Mind, a theory first proposed by Dr. David Premack of the University of Pennsylvania, which is the ability to infer the thoughts of others. In any complex society, anyone with the ability to correctly guess the intentions, motives, and plans of other people has a tremendous survival advantage over those who can’t. The Theory of Mind allows you to form alliances with others, isolate your enemies, and solidify your friendships, which vastly increases your power and chances of survival and mating. Some anthropologists even believe that the mastery of the Theory of Mind was essential in the evolution of the brain.

  Figure 8. Emotions originate and are processed in the limbic system. In Level II consciousness, we are continually bombarded with sensory information, but emotions are rapid-fire responses to emergencies from the limbic system that do not need permission from the prefrontal cortex. The hippocampus is also important for processing memories. So Level II consciousness, at its core, involves the reaction of the amygdala, hippocampus, and prefrontal cortex. (illustration credit 2.2)

  But how is the Theory of Mind accomplished? One clue came in 1996, with the discovery of “mirror neurons” by Drs. Giacomo Rizzolatti, Leonardo Fogassi, and Vittorio Gallese. These neurons fire when you are performing a certain task and also when you see someone else performing that same task. (Mirror neurons also fire for emotions as well as physical acts. If you feel a certain emotion, and think another is feeling that same emotion, then the mirror neurons will fire.)

  Mirror neurons are essential for mimicry and also for empathy, giving us the ability not only to copy the complex tasks performed by others but also to experience the emotions that person must be feeling. Mirror neurons were thus probably essential for our evolution as human beings, since cooperation is essential for holding the tribe together.

  Mirror neurons were first found in the premotor areas of monkey brains. But since then, they have been found in humans in the prefrontal cortex. Dr. V. S. Ramachandran believes that mirror neurons were essential in giving us the power of self-awareness and concludes, “I predict that mirror neurons will do for psychology what DNA did for biology: they will provide a unifying framework and help explain a host of mental abilities that have hitherto remained mysterious and inaccessible to experiments.” (We should point out, however, that all scientific results have to be tested and reconfirmed. There is no doubt that certain neurons are performing this crucial behavior involved with empathy, mimicry, etc., but there is some debate about the identity of these mirror neurons. For example, some critics claim that perhaps these behaviors are common to many neurons, and that there is not a single class of neurons dedicated to this behavior.)

  LEVEL III: SIMULATING THE FUTURE

  The highest level of consciousness, which is associated primarily with Homo sapiens, is Level III consciousness, in which we take our model of the world and then run simulations into the future. We do this by analyzing past memories of people and events, and then simulating the future by making many causal links to form a “causal” tree. As we look at the various faces at the cocktail party, we begin to ask ourselves simple questions: How can this individual help me? How will the gossip floating in the room play out in the future? Is anyone out to get me?

  Let’s say that you just lost your job and you are desperately looking for a new one. In this case, as you talk to various people at the cocktail party, your mind is feverishly simulating the future with each person you talk to. You ask yourself, How can I impress this person? What topics should I bring out to present my best case? Can he offer me a job?

  Figure 9. Simulating the future, the heart of Level III consciousness, is mediated by the dorsolateral prefrontal cortex, the CEO of the brain, with competition between the pleasure center and the orbitofrontal cortex (which acts to check our impulses). This roughly resembles the outline given by Freud of the struggle between our conscience and desires. The actual process of simulating the future takes place when the prefrontal cortex accesses the memories of the past in order to approximate future events. (illustration credit 2.3)

  Recent brain scans have shed partial light on how the brain simulates the future. These simulations are done mainly in the dorsolateral prefrontal cortex, the CEO of the brain, using memories of the past. On one hand, simulations of the future may produce outcomes that are desirable and pleasurable, in which case the pleasure centers of the brain light up (in the nucleus accumbens and hypothalamus). On the other hand, these outcomes may also have a downside to them, so the orbitofrontal cortex kicks in to warn us of possible dangers. There is a struggle, then, between different parts of the brain concerning the future, which may have desirable and undesirable outcomes. Ultimately it is the dorsolateral prefrontal cortex that mediates between these and makes the final decisions. (See Figure 9.) (Some neurologists have pointed out that this struggle resembles, in a crude way, the dynamics between Freud’s ego, id, and s
uperego.)

  THE MYSTERY OF SELF-AWARENESS

  If the space-time theory of consciousness is correct, then it also gives us a rigorous definition of self-awareness. Instead of vague, circular references, we should be able to give a definition that is testable and useful. We’ll define self-awareness as follows:

  Self-awareness is creating a model of the world and simulating the future in which you appear.

  Animals therefore have some self-awareness, since they have to know where they are located if they are going to survive and mate, but it is limited largely by instinct.

  When most animals are placed in front of a mirror, they either ignore it or attack it, not realizing that it is an image of themselves. (This is called the “mirror test,” which goes all the way back to Darwin.) However, animals like elephants, the great apes, bottlenose dolphins, orcas, and European magpies can figure out that the image they see in the mirror represents themselves.

  Humans, however, take a giant step forward and constantly run future simulations in which we appear as a principal actor. We constantly imagine ourselves faced with different situations—going on a date, applying for a job, changing careers—none of which is determined by instinct. It is extremely difficult to stop your brain from simulating the future, though elaborate methods have been devised (for instance, meditation) to attempt to do so.

  Daydreaming, as an example, consists largely of our acting out different possible futures to attain a goal. Since we pride ourselves in knowing our limitations and strengths, it is not hard to put ourselves inside the model and hit the “play” button so we begin to act out hypothetical scenarios, like being an actor in a virtual play.