You Are Not So Smart: Why You Have Too Many Friends on Facebook, Why Your Memory Is Mostly Fiction, and 46 Other Ways You're Deluding Yourself (4 page)

Split-brain patients seem fine from the outside. They are able to hold down jobs and carry their weight in conversation. But researchers who have looked deeper have discovered the strengths and weaknesses of the separate hemispheres with the help of split-brain patients. Since the 1950s, studies with those who have undergone this procedure have revealed a great deal about how the brain works, but the insight most germane to the topic at hand is how quickly and unflinchingly these patients are capable of creating complete lies which they then hold to as reality. This is called split-brain confabulation, but you don’t have to have a split brain to confabulate.

You feel like a single person with a single brain, but in many ways, you really have two. Thoughts, memories, and emotions cascade throughout the whole, but some tasks are handled better by one side than the other. Language, for example, is usually a task handled by the left side of the brain, but then bounced back and forth between the two. Strange things happen when a person’s brain hemispheres are disconnected, making this transfer impossible.

Psychologist Michael Gazzaniga at the University of California at Santa Monica was one of the first researchers, along with Roger Sperry, to enlist the help of split-brain patients in his work. In one experiment subjects looked at a cross in the center of a computer screen, and then a word like “truck” was flashed on only the left side. They were then asked what they saw. Those with connected brains would, of course, say “truck.” Those with split brains would say they didn’t know, but then, amazingly, if they were asked to draw with their left hand what they had seen, they easily doodled a truck.

Oddly enough, your right hand is controlled by your left brain and your left hand by the right. What the left eye sees travels diagonally through the cranium into the right hemisphere and vice versa, and these nerves are not severed when the brains are split.
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Normally this isn’t a problem, because what one side of the brain perceives and thinks gets transmitted to the other, but a split-brain can’t say what they see when a scientist shows an image to the left visual field. The language centers are in the other hemisphere, across from where the image is being processed. The part of their brain in charge of using words and sending them to the mouth can’t tell the other side, the one holding the pencil, what it is looking at. The side that saw the image can, however, draw it. Once the image appears, the split-brain person will then say, “Oh, a truck.” The communication that normally takes place across the corpus callosum now happens on the paper.

This is what goes on in the world of a split-brain patient. The same thing happens in your head too. The same part of your brain is responsible for turning thoughts into words and then handing those words over to the mouth. All day long, the world appearing in your right hemisphere is being shared with your left in a conversation you are unaware of. At the biological level, this is a fundamental source of confabulation, and it can be demonstrated in the lab.

If split-brain people are shown two words like “bell” on the left and “music” on the right and then asked to point out with their right hand in a series of four photos what they saw, they will point to the image with a bell in it. They will ignore other photos of a drummer, an organ, and a trumpet. The amazing confabulatory moment happens when they are asked why they chose the image. One split-brain patient said it was because the last music they heard was coming from the college’s bell towers. The left eye saw a bell, and told the right hand to point to it, but the right side saw music and was now concocting a justification for ignoring the other pictures that were also related to the idea.

The side of the brain in charge of speaking saw the other side point out the bell, but instead of saying it didn’t know why, it made up a reason. The right side was no wiser, so it went along with the fabrication. The patients weren’t lying, because they believed what they were saying. They deceived themselves and the researcher but had no idea they were doing so. They never felt confused or deceptive; they felt no different than you would.

In one experiment a split-brain person was asked to perform an action only the right hemisphere could see, and the left hemisphere once again explained it away as if it knew the cause. The word “walk” was displayed; the subject stood. When the researcher asked why he got up, the subject said, “I need to get a drink.” Another experiment showed a violent scene to only the right hemisphere. The subject said she felt nervous and uneasy and blamed it on the way the room was decorated. The deeper emotional centers could still talk to both sides, but only the left hemisphere had the ability to describe what was bubbling up. This split-brain confabulation has been demonstrated many times over the years. When the left hemisphere is forced to explain why the right hemisphere is doing something, it often creates a fiction that both sides then accept.

Remember though, your brain works in the same way—you just have the benefit of a connection between the two halves to help buffer against misunderstandings, but they can still happen from time to time. Psychologist Alexander Luria compared consciousness to a dance and said the left hemisphere leads. Since it does all the talking, it sometimes has to do all the explaining. Split-brain confabulation is an extreme and amplified version of your own tendency to create narrative fantasies about just about everything you do, and then believe them. You are a confabulatory creature by nature. You are always explaining to yourself the motivations for your actions and the causes to the effects in your life, and you make them up without realizing it when you don’t know the answers. Over time, these explanations become your idea of who you are and your place in the world. They are your self.

The neuroscientist V. S. Ramachandran once encountered a split-brain patient whose left hemisphere believed in God, but whose right hemisphere was an atheist. Essentially, as he put it, there were two people in one body—two selves. Ramachandran believes your sense of self is partly the action of mirror neurons. These complex clusters of brain cells fire when you see someone hurt themselves or cry, when they scratch their arm or laugh. They put you in the other person’s shoes so you can almost feel that person’s pain and itches. Mirror neurons provide empathy and help you learn. One of the greatest discoveries in recent years was to find that mirror neurons fire also when
you
do things. It is as if part of your brain is observing yourself as an outsider.

You are a story you tell yourself. You engage in introspection, and with great confidence you see the history of your life with all the characters and settings—and you at the center as protagonist in the tale of who you are. This is all a great, beautiful confabulation without which you could not function.

As you move through your day, you imagine a wide range of potential futures, potential situations outside your senses. When you read news articles and nonfiction books, you create fantasy worlds for situations that actually did happen. When you recall your past, you create it on the spot—a daydream part true and part fantasy that you believe down to the last detail. If you were to lie back and imagine yourself sailing around the world, seeing all the wonders of the planet from one port to the next, you could with varying levels of detail imagine the entire globe from Paris to India, from Cambodia to Kansas, but you know you haven’t actually taken this trip. And there are severe brain disorders where sufferers cannot sort out their own confabulations:

Psychologists have long assumed that you aren’t aware of your higher cognitive processes, as Richard Nisbett and Timothy DeCamp Wilson at the University of Michigan suggested in their 1977 article for
Psychological Review
. In their paper they shot holes in the idea of introspection, saying you are rarely aware of the true stimuli that have led to your responses over the years, even from one day to the next. In one study, they write, subjects were asked to think of their mother’s maiden name.

Go ahead. You try. What is your mother’s maiden name?

The next question in the study was “How did you come up with that?”

So how did you?

You don’t know. You just thought it. How your mind works is something you can never access, and although you often believe you understand your thoughts and actions, your emotions and motivations, much of the time you do not. The very act of looking inward is already several steps removed from the thoughts you are remembering. This, however, doesn’t prevent you from assuming you really do know, you really can recall in full detail, and this is how narratives begin. This is how confabulation provides a framework from which to understand yourself.

As the psychologist George Miller once said, “It is the result of thinking, not the process of thinking, that appears spontaneously in consciousness.” In other words, in many ways you are only reporting on what your mind has already produced instead of directing its performance. The flow of consciousness is one thing; the recollection of its course is another, yet you usually see them as the same. This is one of the oldest concepts in psychology and philosophy—phenomenology. It was one of the first debates among researchers over just how deep psychology could delve into the mind. Since the early 1900s, psychologists have wrestled with the conundrum of how, at a certain level, subjective experience can’t be shared. For instance, what does red look like? What do tomatoes smell like? When you stub your toe, what does it feel like? What would you say if you had to explain any of these to someone who had never experienced them? How would you describe red to a person blind from birth or the scent of a fresh tomato to someone who had never smelled before?

These are qualia, the deepest you can tunnel down into your experience before you hit rock. Most everyone has seen red but can’t explain what it is like to do so. Your explanations of experience can build up from qualia but can’t go any lower. These are the ineffable building blocks of consciousness. You can explain them only in relation to other experiences, but you can never completely describe the experience of qualia to another person, or yourself.

There is more at work in your mind than you can access; beneath the rock there is more complexity to your thoughts and feelings than you can directly behold. For some behaviors, the antecedent is something old and evolved, a predilection passed down through thousands of generations of people like you trying to survive and thrive. You want to take a nap on a rainy afternoon because perhaps your ancestors sought shelter and safety in the same conditions. For other behaviors, the impetus may have come from something you simply didn’t notice. You don’t know why you feel like leaving in the middle of Thanksgiving dinner, but you come up with an explanation that seems to make sense at the time. Looking back, the explanation may change.

Philosopher Daniel Dennett calls seeing yourself in this way heterophenomenology. Basically, he suggests when you explain why you feel the way you do, or why you behaved as you did, to take it with a grain of salt, as if you were listening to someone tell you about their night out. When you listen to someone else tell a story, you expect some embellishment and you know they are only telling you how the events seemed to transpire to them. In the same way, you know how reality seems to be unfolding, how it seems to have unfolded in the past, but you should take your own perception with a grain of salt.

In the Miller and Nisbett paper, they cited many studies in which people were aware of their thoughts but not how they arrived at them. Despite this, subjects usually had no problem providing an explanation, an introspection, which failed to address the true cause. In one, two groups were given electric shocks while they performed memory tasks. Both groups were then asked to run through the tasks again after the experiment ended. One group was told the second set of shocks was important in the pursuit of understanding the human mind. The other group was told the new round of shocks was just being used to satisfy the scientist’s curiosity. The second group then performed better on the memory tasks, because they had to come up with their own motivation for continuing, which was to believe the shocks didn’t hurt. In their minds the shocks really didn’t hurt as much as they did for the first group, at least they said as much when interviewed later.

In another study, two groups of people who said they were very afraid of snakes were shown slides of snakes while listening to what they believed was their heart rate. Occasionally one group would see a slide with the word “shock” printed on it. They were given a jolt of electricity when they saw this slide, and the researchers falsely increased the sound of the beating of their hearts in the monitor. When they later were asked to hold a snake, they were far more likely to give it a shot than the group who didn’t see the shock slide and hear a fake increase in heart rate. They had convinced themselves they were more afraid of being shocked than of snakes and then used this introspection to truly be less afraid.