Scientists are looking for your soul | wibnet.nl

First, the doctors asked him to open and close one hand. Then they asked him to release his hand. Maria Mazurkevich did not move – but the electrodes on her head showed that she had heard the doctors.

The electrodes had picked up electrical impulses from the brain, showing that the patient not only responded to what the doctors said, but also heard the difference between the requests.

She was therefore well aware of her surroundings – and the doctors got a unique insight into her consciousness.

Maria Mazurkevich’s story could help solve one of science’s greatest mysteries.

For thousands of years the brilliant minds of the world have tried to figure out what consciousness is and where it resides. Some call it the soul, and many say it’s a separate entity that can even leave the body.

Like other mental properties, consciousness probably resides in the brain – but unlike, say, our ability to recognize faces or formulate a sentence, consciousness is frustratingly elusive and impossible to locate in the jumble of nerve cells. .

But a revolutionary international project aims to change that.

Easy problems are hard

It is difficult to say what consciousness is. But an important characteristic of it is our feeling about the experience we have of the world. Psychologists and neurologists call these feelings qualia.

When we look at a ripe tomato, the brain registers light with a wavelength of 660 nanometers, which is red by definition. However, we do not experience the color red as a wavelength, but as an indefinable sense of “red”.

And when the volatile chemicals in tomatoes hit the sensory cells in our noses, we don’t smell methyl salicylate and benzaldehyde, but a pleasant tomato smell.

Qualia are about the experience of color, sound, smell, taste, and tickle, but also about falling in love or sadness, or the realization that you are reading this article.

Understanding how qualia arise and are interpreted in the brain is what scientists call “the difficult problem of consciousness.” And it is probably not only solvable by the natural sciences, but extends far into the abstract thought of psychology and philosophy.

Unlike the somewhat more philosophical “difficult problem”, the “easy problems of consciousness” are more concrete. The point here is not to understand how our experience of consciousness arises, but to identify the complex circuits of the brain that lead to our consciousness.

These problems are easy only in the sense that they are more tangible than the hard problem and can be tackled using standard scientific methods. In all other respects, they are almost insurmountable.

Fortunately, this challenge does not discourage scientists. In one of the most ambitious scientific projects of all time, researchers around the world want to dig into every brain cell to find the seat of consciousness.

The soul hides in turbulence

The Human Brain Project is a collaboration of at least 500 scientists from 16 countries. The project aims, among other things, to map the 86 billion nerve cells in our brain and to study how communication between nerve cells determines our thoughts and behavior.

The Human Brain Project has already made a number of important discoveries. In 2022, two project researchers, Denmark’s Morten Kringelbach and Italy’s Gustavo Deco, examined the brain scans of more than 1,000 people to find out how information and energy travel through nerve cells in part of the brain to another.

Researchers discovered that consciousness is the result of turbulence in the brain. This turbulence occurs when the brain’s information and energy flows are chaotic in both time and space, allowing information to be transferred much more efficiently.

The phenomenon can be compared to soup, where the ingredients mix much faster if you beat back and forth rather chaotically than if you gently turn your spoon in the pan.

Thus, information and energy flows are more chaotic when people are fully conscious, and not in an unconscious state like deep sleep and coma.

It was also found that fully conscious subjects had a greater flow of information over long distances than subjects in a coma. And conversely, people in comas had a greater flow of information over short distances in the brain.

In sleeping subjects, the exchange of information over short and long distances was weak.

The finding is a breakthrough, but exactly what it will mean for our understanding of consciousness is still unclear. Its meaning will only become clear when we have a more complete picture of the brain.

Water indicates main roads

A map of all neurons was still a dream until now. But with the latest advanced techniques, the Human Brain Project wants to make this dream come true.

One such technique, 3D-PLI, was developed by German physicist Markus Axer. The technique involves cutting the brains of deceased people into slices and then taking pictures of each slice. The computer merges the images into a 3D model of the brain and all its cells.

New techniques can also be used to map the brains of living people in unprecedented detail. For example, with a special type of MRI, scientists can follow the movements of water molecules along nerve bundles.

The scanning method clearly shows the size and extent of the nerve pathways. The thick bundles of nerves between two brain centers indicate that many signals are exchanged – so these are the main pathways of the brain.

This level of detail makes it much more accurate to determine how the maze of electrical impulses in the brain give rise to certain thoughts or emotions – and our consciousness.

Doctors turn on the conscience

In addition to new techniques, this exploration of our consciousness is also based on extraordinary stories, such as that of Maria Mazurkevich. She appeared to be in a coma, but seemed conscious.

If researchers at the Human Brain Project can scan the brains of people like them, we might better understand how turbulence in the brain leads to consciousness – or how specific bundles of nerves create that special feeling we get when we do the experience of the world.

This knowledge, in turn, can help us understand the mechanistic, “easy,” problems of consciousness. And if we understand this, we are also better able to solve the difficult, more philosophical problem.

The research will also have important practical applications. This will allow doctors to better determine which patients in comas are fully conscious – even to reactivate the consciousness of those in comas.

At least for Maria Mazurkevich, the story ended well.

After a week, her body began to follow electrical signals from the brain so she could shake hands when doctors asked. And after a year she was completely recovered. Now she works as a pharmacy assistant.