The Future of the Mind (29 page)

This system also emits chemicals that decouple parts of the brain involved with reason and logic. The lack of checks coming from the prefrontal and orbitofrontal cortices, along with the brain becoming extremely sensitive to stray thoughts, may account for the bizarre, erratic nature of dreams.

Studies have shown that it is possible to enter the cholinergic state without sleep. Dr. Edgar Garcia-Rill of the University of Arkansas claims that meditation, worrying, or being placed in an isolation tank can induce this cholinergic state. Pilots and drivers facing the monotony of a blank windshield for many hours may also enter this state. In his research, he has found that schizophrenics have an unusually large number of cholinergic neurons in their brain stem, which may explain some of their hallucinations.

To make his studies more efficient, Dr. Allan Hobson had his subjects put on a special nightcap that can automatically record data during a dream. One sensor connected to the nightcap registers the movements of a person’s head (because head movements usually occur when dreams end). Another sensor measures movements of the eyelids (because REM sleep causes eyelids to move). When his subjects wake up, they immediately record what they dreamed about, and the information from the nightcap is fed into a computer.

In this way, Dr. Hobson has accumulated a vast amount of information about dreams. So what is the meaning of dreams? I asked him. He dismisses what he calls the “mystique of fortune-cookie dream interpretation.” He does not see any hidden message from the cosmos in dreams.

Instead, he believes that after the PGO waves surge from the brain stem into the cortical areas, the cortex is trying to make sense of these erratic signals and winds up creating a narrative out of them: a dream.

PHOTOGRAPHING A DREAM

In the past, most scientists avoided the study of dreams, since they are so subjective and have such a long historical association with mystics and psychics.
But with MRI scans, dreams are now revealing their secrets. In fact, since the brain centers that control dreaming are nearly identical to the ones that control vision, it is therefore possible to photograph a dream. This pioneering work is being done in Kyoto, Japan, by scientists at the ATR Computational and Neuroscience Laboratories.

Subjects are first placed in an MRI machine and shown four hundred black-and-white images, each consisting of a set of dots within a ten-by-ten-pixel framework. One picture is flashed at a time, and the MRI records how the brain responds to each collection of pixels. As with other groups working in this field of BMI, the scientists eventually create an encyclopedia of images, with each image of pixels corresponding to a specific MRI pattern. Here the scientists are able to work backward, to correctly reconstruct self-generated images from MRI brain scans taken while the subject dreams.

ATR chief scientist Yukiyasu Kamitani says, “This technology can also be applied to senses other than vision. In the future, it may also be possible to read feelings and complicated emotional states.” In fact, any mental state of the brain might be imaged in this way, including dreams, as long as a one-to-one map can be made between a certain mental state and an MRI scan.

The Kyoto scientists have concentrated on analyzing still photographs generated by the mind. In
Chapter 3
, we encountered a similar approach pioneered by Dr. Jack Gallant, in which the voxels from 3-D MRI scans of the brain can be used to reconstruct the actual image seen by the eye with the help of a complex formula. A similar process has allowed Dr. Gallant and his team to create a crude video of a dream.
When I visited the laboratory in Berkeley, I talked to a postdoctoral staff member, Dr. Shinji Nishimoto, who allowed me to watch the video of one of his dreams, one of the first ever done. I saw a series of faces flickering across the computer screen, meaning that the subject (in this case Dr. Nishimoto himself) was dreaming of people, rather than animals or objects. This was amazing. Unfortunately, the technology is not yet good enough to see the precise facial features of the people appearing in his dream, so the next step is to increase the number of pixels so that more complex images can be identified. Another advance will be to reproduce images in color rather than black and white.

I then asked Dr. Nishimoto the crucial question: How do you know the video is accurate? How do you know that the machine isn’t just making things up? He was a bit sheepish when he replied that this was a weak point
in his research. Normally, you have only a few minutes after waking up to record a dream. After that, most dreams are lost in the fog of our consciousness, so it is not easy to verify the results.

Dr. Gallant told me that this research on videotaping dreams was still a work in progress, and that is why it’s not ready for publication. There is still a ways to go before we can watch a videotape of last night’s dream.

LUCID DREAMS

Scientists are also investigating a form of dreaming that was once thought to be a myth: lucid dreaming, or dreaming while you are conscious. This sounds like a contradiction in terms, but it has been verified in brain scans. In lucid dreaming, dreamers are aware that they are dreaming and can consciously control the direction of the dream. Although science has only recently begun to experiment with lucid dreaming, there are references to this phenomenon dating back centuries. In Buddhism, for example, there are books that refer to lucid dreamers and how to train yourself to become one. Over the centuries, several people in Europe have written detailed accounts of their lucid dreams.

Brain scans of lucid dreamers show that this phenomenon is real; during REM sleep, their dorsolateral prefrontal cortex, which is usually dormant when a normal person dreams, is active, indicating that the person is partially conscious while dreaming. In fact, the more lucid the dream, the more active the dorsolateral prefrontal cortex. Since the dorsolateral prefrontal cortex represents the conscious part of the brain, the dreamer must be aware while he or she is dreaming.

Dr. Hobson told me that anyone can learn to do lucid dreaming by practicing certain techniques. In particular, people who do lucid dreaming should keep a notebook of dreams. Before going to sleep, they should remind themselves that they will “wake up” in the middle of the dream and realize that they are moving in a dream world. It is important to have this frame of mind before hitting the pillow. Since the body is largely paralyzed during REM sleep, it is difficult for the dreaming person to send a signal to the outside world that he has entered a dream, but Dr. Stephen LaBerge at Stanford University has studied lucid dreamers (including himself) who can signal the outside world while dreaming.

In 2011, for the first time, scientists used MRI and EEG sensors to measure dream content and even make contact with a dreaming person. At the Max Planck Institute in Munich and Leipzig, scientists enlisted the help of lucid dreamers, who were fitted with EEG sensors on their heads to help the scientists determine the moment they entered REM sleep; they were then placed in an MRI machine. Before falling asleep, the dreamers agreed to initiate a set of eye movements and breathing patterns when dreaming, like a Morse code. They were told that once they started dreaming, they should clench their right fist and then their left one for ten seconds. That was the signal that they were dreaming.

The scientists found that, once the subjects entered their dream state, the sensorimotor cortex of the brain (responsible for controlling motor actions like clenching your fists) was activated. The MRI scans could pick up that the fists were being clenched and which fist was being clenched first. Then, using another sensor (a near-infrared spectrometer) they were able to confirm that there was increased brain activity in the region that controls the planning of movements.

“
Our dreams are therefore not a ‘sleep cinema’ in which we merely observe an event passively, but involve activity in the regions of the brain that are relevant to the dream content,” says Michael Czisch, a group leader at the Max Planck Institute.

ENTERING A DREAM

If we can communicate with a dreaming person, then is it also possible to alter someone’s dream from the outside? Quite possibly.

First, as we have seen, scientists have already made the initial steps in videotaping a person’s dream, and in the coming years, it should be possible to create much more accurate pictures and videos of dreams. Since scientists have already been able to establish a communication link between the real world and the lucid dreamer in the fantasy world, then, in principle, scientists should be able to deliberately alter the course of a dream. Let’s say that scientists are viewing the video of a dream using an MRI machine as the dream unfolds in real time. As the person wanders around the dreamscape, the scientists can tell where he is going and give directions for him to move in different ways.

So in the near future, it might be possible to watch a video of a person’s dream and actually influence its general direction. But in the movie
Inception
, Leonardo DiCaprio goes much further. He is able not only to watch another person’s dream, but also to enter it. Is this possible?

We saw earlier that we are paralyzed when we dream so that we don’t carry out our dream fantasies, which might be disastrous. However, when people are sleepwalking, they often have their eyes open (although their eyes look glazed over). So sleepwalkers live in a hybrid world, part real and part dreamlike. There are many documented instances of people walking around their homes, driving cars, cutting wood, and even committing homicides while in this dream state, where reality and the fantasy world are mixed. Hence it is possible that physical images that the eye actually sees can freely interact with the fictitious images that the brain is concocting during a dream.

The way to enter someone’s dream, then, might be to have the subject wear contact lenses that can project images directly onto their retinas.
Already, prototypes of Internet contact lenses are being developed at the University of Washington in Seattle. So if the observer wanted to enter the subject’s dream, first he would sit in a studio and have a video camera film him. His image could then be projected onto the contact lenses of the dreamer, creating a composite image (the image of the observer superimposed upon the imaginary image the brain is manufacturing).

The observer could actually see this dream world as he wanders around the dream, since he, too, would be wearing Internet contact lenses. The MRI image of the subject’s dream, after it has been deciphered by computer, would be sent directly into the observer’s contact lenses.

Furthermore, you could actually change the direction of the dream you have entered. As you walk around in the empty studio, you would see the dream unfold in your contact lens, so you could start to interact with the objects and people appearing in the dream. This would be quite an experience, since the background would change without warning, images would appear and disappear without reason, and the laws of physics would be suspended. Anything goes.

Further into the future, it might even be possible to enter another person’s dream by directly connecting two sleeping brains. Each brain would have to be connected to MRI scanners that were connected to a central computer, which would merge the two dreams into a single one. The computer
would first decipher each person’s MRI scans into a video image. Then the dream of one person would be sent into the sensory areas of the other person’s brain, so that the other dreamer’s dream would merge with the first dreamer’s dream. However, the technology of videotaping and interpreting dreams would have to become much more advanced before this could become a possibility.

But this raises another question: If it’s possible to alter the course of someone’s dream, is it possible to control not only that person’s dream but that person’s mind as well? During the Cold War, this became a serious issue as both the Soviet Union and the United States played a deadly game, trying to use psychological techniques to control other people’s wills.

Minds are simply what brains do.

—MARVIN MINSKY

8
CAN THE MIND BE CONTROLLED?

A raging bull is released into an empty arena in Cordoba, Spain. For generations, this ferocious beast has been carefully bred to maximize its killer instinct. Then a Yale professor calmly enters the same arena. Rather than donning a tweed jacket, he is dressed like a dashing matador, wearing a bright golden jacket and waving a red cape defiantly in front of the bull, egging him on. Instead of running away in terror, the professor looks calm, confident, and even detached. To a bystander, it appears as if the professor has gone mad and wants to commit suicide.

Enraged, the bull locks onto the professor. Suddenly the bull charges, aiming his deadly horns at him. The professor does not run away in fear. Instead, he holds a small box in his hand. Then, in front of the cameras, he presses a button on the box, and the bull stops dead in his tracks. The professor is so confident of himself that he has risked his life to prove a point, that he has mastered the art of controlling the mind of a mad bull.

The Yale professor is Dr. José Delgado, who was years ahead of his time. He pioneered a series of remarkable but unsettling animal experiments in the 1960s, in which he put electrodes into their brains with the aim of trying
to control their movement. To stop the bull, he inserted electrodes into the striatum of the basal ganglia at the base of the brain, which is involved with motor coordination.

He also did a series of other experiments on monkeys to see if he could rearrange their social hierarchy with the push of a button. After implanting electrodes into the caudate nucleus (a region associated with motor control) of the alpha male within the group, Delgado could reduce the aggressive tendencies of the leader on command. Without threats of retaliation, the delta males began to assert themselves, taking over the territory and privileges normally reserved for the alpha male. The alpha male, meanwhile, appeared to have lost interest in defending his territory.