Make a bet on consciousness

  Twenty years ago, two top scholars gambled on whether they could find a neurological explanation for consciousness. Twenty years have passed, now let’s review this gamble.
  A drink after the bet
  In 1998, two young people sat in a smoky bar in Bremen, Germany. They are the American neuroscientist Christopher Koch and the Australian philosopher David Chalmers, who came to the city to participate in a conference to discuss consciousness. After spending a whole day at the conference, they still have a lot to say.
  After drinking a few drinks, Koch suggested a gamble. He bet a box of fine wines and believes that in the next 25 years, someone will find a small number of nerve cells in the brain whose intrinsic properties can be linked to a particular consciousness activity. Here, the intrinsic property can refer to the discharge pattern that nerve cells have, or that some of its genes can control the production of various neurotransmitters, and so on. Chalmers bet that this is unlikely to happen.
  This is a fun and bold gamble, after all, consciousness is a very mysterious subjective thing. The feelings of blue, the feeling of love, the feeling of pain, and all your other subjective experiences are your consciousness, which emerges in some way in your brain.
  In the past, people thought that consciousness was not a scientific research object. Today, consciousness is a hot research area, and Koch and Chalmers are two of their most influential people. Koch is the director of the Allen Institute of Brain Science in Seattle, USA, and Chalmers is the director of the Center for Mind, Brain, and Consciousness at New York University.
  Twenty years have passed, how far are we from the mystery of cracking consciousness? Next, we try to answer this question by discussing the gambling of Koch and Chalmers.
  Does consciousness come from certain nerve cells?
  This gamble on consciousness originated from Koch’s research. In the mid-1980s, as a young scientist, he began working with British biologist Francis Crick, one of the scientists who discovered the double helix structure of DNA. Both people were dissatisfied with the progress of scientific research at that time. In fact, the International Psychology Dictionary describes consciousness: “This is a fascinating but elusive phenomenon. What it is, what it does, why it evolved, it is impossible to clarify. About it None of the books is worth reading.” The
  two believe that this is partly because the researchers did not find an effective way to solve the problem. In the process of studying DNA, Crick attributes the mystery of biological inheritance to some intrinsic properties of a small group of molecules, that is, the base sequences of DNA and RNA molecules can form a genetic code. He and Koch believe that consciousness can be explained in a similar way. What they want to do is to find a small number of nerve cells whose intrinsic properties can be linked to a particular consciousness activity. In other words, they want to find a “neural correlation of consciousness.”
  Since then, the search for neural correlates of consciousness has become the core of the research consciousness of scientists. Some studies suggest that gamma waves are related to human consciousness activities. Gamma waves are brain waves generated when nerve cells move, and their frequencies are usually around 40 Hz. In addition, other studies have pointed out that pyramidal cells in the cerebral cortex may play a key role in human consciousness activities (see “Where is consciousness?”).
  However, many of the early models have proven to be too simple. For example, in the view that Koch and Crick once supported, they believe that a flaky structure called the screen-like body in the cerebral cortex is a switch of conscious activity. A study done in 2014 supports the idea that electrically stimulating this structure of a woman’s brain will make her stare blankly at the front, seemingly an unconscious act until the stimulus stops. However, another study denied this idea. This study recorded a patient with complete damage to the screen due to encephalitis, but he still had normal consciousness activities.
  Does consciousness come from a certain neural network?
  Scientists looking for neural correlates of consciousness have not retreated, and they have come up with more complex ideas that consciousness is more likely to be related to neural networks than to specific nerve cells. A view called the Global Workspace Theory is particularly influential. According to this view, information from the outside world competes for attention in the cerebral cortex and in the structure called the thalamus at the center of the brain. If a signal beats other signals, it will spread throughout the brain. Only then will you notice this signal and enter your consciousness. For example, your cerebral cortex may also receive a breeze to the skin, a pair of shoes to the feet, and the itching of mosquitoes when you bite. The itching sensation may overcome other sensations and enter your consciousness, so you will notice that mosquitoes are biting you.
  Another point that has attracted a lot of attention is the integration of information theory, which was proposed by neuroscientist Julio Toononi of the University of Wisconsin. He believes that any system has consciousness. Consciousness is generated when a system of information is processed and integrated, not just the sum of the parts, and the amount of consciousness (called what he calls Φ) is measurable. For a system, if the parts can communicate with each other quickly and efficiently, then its Φ value will be high. For example, the cerebral cortex has a high Φ value. In contrast, the Φ value of the cerebellum will be relatively low. A person has about 86 billion nerve cells, of which there are about 69 billion nerve cells in the cerebellum. Although the number of nerve cells in the cerebellum is large, the cerebellum is composed of many parts that work independently of each other, so the Φ value is relatively low.
  The global workspace theory seems to coincide with many discoveries about the brain. Some studies have shown that some nerve cells located in the front of the cerebral cortex have the ability to transmit signals throughout the brain. However, it did not convince some people. They questioned that this theory only explains how consciousness works, but what consciousness itself, such as the feeling that a color gives you, is still unexplained by the theory.
  Integrated information theory is also consistent with some phenomena. For example, a stroke or tumor may damage the cerebellum, but it does not significantly affect consciousness, and similar damage to the cerebral cortex often interferes with the subjective experience of the person and may even lead to coma. But this theory is controversial because it assumes that inanimate things are also conscious, that is, “everything has spirituality.” In addition, the theory also means that some complex integrated circuits may be highly aware. But this theory also has some high-profile supporters. One of them is Koch.
  Who will win this gamble?
  Koch’s original point of view was to attribute consciousness to certain intrinsic properties of a small number of nerve cells. Now, he began to choose to support the integration of information theory. He believes that the best candidate for the current neural correlate of consciousness is located in the back of the cerebral cortex. He called it a “hot spot” and pointed out that the Φ value there is quite high compared to other brain regions, which is due to more neural connections there. Thus, according to the theory of integrated information, it is more closely related to consciousness.
  But Chalmers emphasized the details of the gambling. He believes that Koch’s “hot spot” does not seem to be seen as a small number of nerve cells. In addition, he believes that things related to Φ should not be counted as intrinsic properties of a small number of nerve cells, they should be seen as an external property of a set of neural networks. Chalmers believes that he is likely to win this gamble.
  Koch agrees with Chalmers, but he does not completely give up all hope. “A lot of things can happen in five years!”
  By 2023, the outcome of this gambling will be determined. But no matter who wins, Koch and Chalmers are convinced that finding nerve-related objects of consciousness is an important scientific task. However, there is still a certain gap between finding the relevant things and fully understanding the consciousness. So, is consciousness a mystery that can never be solved? Koch has a negative attitude towards this. However, Chalmers is more cautious. He believes that consciousness may even be something that cannot be explained at all, but we have to try to crack it to know.