More than 98% of species that once existed disappeared, having been replaced by others. In this context, the human species has had an extraordinary fate. The Natural Selection has programmed all the elements of human biology, from the finger to the neurological circuits in the brain.
The human product has been tested and many times reviewed in thousands of generations of geological life. Even so, we are immersed in a world of pathologies and deficiencies. Neuronal diseases and brain disturbances affect 2 billion people worldwide.
It is expected that in 2050, One in every three to five people can have dementia. As we discover more, for example, about cardiovascular diseases, we can prevent and increase our life expectancy. Therefore, it is natural that children who are born now are said to live up to 120 years.
If we do nothing about the brain, our brain today begins to decline. and there is a lot of dementia from the 80s and it will increase with age. If we don't discover the equivalent for the brain, we will live more, but without a brain that can accompany these last years of life. I'm extremely gratified that countries throughout the world are beginning to realize that the final frontier for human beings is not outer space. but it's inner space.
It's learning something about how our brains work. This remains the most embarrassingly weak part of our medical treatment of human disease. We do much better with all other organ systems than we do with the brain. Behind the great objective of decoding the human brain, there are common global concerns. Cutting paths in the development of artificial intelligence, but above all finding solutions to prevent or remedy neurodegenerative diseases that affect in large numbers and in a transversal way developed and developing countries.
the entire human brain to the tune of billions of dollars because of mental illness. Mental illness is one of the great curses of our ancient genetic ancestry. It has haunted human history.
Kings and queens have suffered from mental illness and have ruined the destiny of their countries. We are just at the infancy of this attempt because we are just beginning to understand how to... Analyze normal human and normal animal brain tissue.
Once we have a good sense of what normal means, what does a wiring diagram, what is it supposed to look like, I think we'll be in a better position to compare those wiring diagrams with the diagrams of animals or, if we can get samples from humans, of disordered nervous systems. Memory deficits are one of the biggest unaddressed problems in medicine. So this is a huge problem. By some measurement it affects one in five people worldwide.
And for the first time we are making inroads not only in understanding memory, but using what we are learning to develop treatments for memory disorders. As we get older and capitalize on experience and wisdom, it would be desirable for us to walk towards a full life with health. But with aging, the system's failures are intensifying.
It is estimated that in 2080, there are 3.4 million people with over 100 years. Currently, Alzheimer's disease is responsible for half of the cases of dementia. It is estimated that the number doubles until the middle of the century, in case neuroscience fails to reverse the trend. for example, that Alzheimer's disease is not a disease of the elderly, but it's a disease that develops over decades. And so when you look at somebody who is terribly demented with Alzheimer's disease, that may be a result of something that happened 30, 40, or even 50 years earlier, triggered and developed over a long period of time.
We certainly have much better understanding of Alzheimer's disease compared to even 5, 10 years ago. However, there is still a long way to go. And with the help of deep learning, AI, and with the help of many different kinds of scientific disciplines such as genetics, biochemistry, also with clinical science, we believe that we'll get to understand Alzheimer's disease much better than before.
As is already happening with Parkinson's disease, the reduction of the disability of Alzheimer's patients may come to pass in the future through the incorporation of a chip. Today, however, it is already possible to know with great precision what is the probability of developing the disease with all the side effects that this may bring. Our group decided to apply deep learning, a type of artificial intelligence algorithm, to analyze PET scans of the brain.
And then we were able to make predictions on whether a patient will be developing Alzheimer's disease about six years earlier before the final diagnosis. So for example, when we have the PET scan, Alzheimer's disease affects the brain in a way that's really diffused and subtle throughout the entire brain, and it shows up in a subtle manner in the imaging modality. What deep learning does is after seeing hundreds to thousands of examples of Alzheimer's disease patients, and also about a hundred thousands of normal patients, it's able to detect these subtle differences in patterns between the two populations and then extrapolate that, okay, so without necessarily understanding the deep mechanism of how Alzheimer's disease works, it's able to really pick up those patterns in a superb way.
and intervene. There are aspects that will change a bit the way we live in society. Because imagine, knowing that I will have Alzheimer's and Echidna, or that I will have, with a great probability, a certain cancer, that I will have a certain type of disease, can change the way I feel today. So it's complex.
Unfortunately, there is no definitive cure for Alzheimer's disease at the moment. And some critics of my research have mentioned that, what is the point of diagnosing Alzheimer's disease early if we just tell them the bad news six years early and then they'll be really sad for another six more years. But our argument is that if you cannot diagnose a condition early enough, then there is no chance of creating any treatment for the condition. We can now record memories. That was once considered impossible.
How can you record a memory? We didn't even know her memories were stored. Let alone record them, but now we can send memories on the internet.
And here's how we do it. At the center of the brain is the hippocampus. It's about that big. It's where short-term memories are stored. We can put two electrodes on either side of the hippocampus and measure.
The impulses going back and forth and recorded like a tape recorder. And then months later, we can take that tape recording tape, put it back into the brain of an animal, and the animal remembers. This can now be done with mice.
It's now being done on primates. And eventually, we'll do it on Alzheimer's patients. You see, Alzheimer's patients in the future may have a memory chip.
They'll simply push a button, and memories. Another area that is very promising has to do with the implant of stem cells which are transformed into dopamine cells again in the brain to replace those cells that died from Parkinson's disease. If we lose the neurons that produce dopamine, we have Parkinson's.
If we have excess dopamine, we often have hyperactivity, we can't control what we do. Diagnostic processes are more effective today. Still, the evolutionary trend of some pathologies that affect children and young people is worrying. In 20 years, the prevalence of anxiety in children has increased from 1 to 20%.
Language disorders are also increasing. Two-thirds of children under judicial custody have language difficulties. The problem that the 21st century has to detect carefully, knowing that throughout evolution, language has become a crucial instrument for the survival of the most apt. disorder that has at the moment no cure and not even a cause we hope the path we are following will be useful in generating ultimately a rational approach to these illnesses and the situations acquired such as mental pathology associated with depression, anxiety, behaviors related to attention and education, the relationship with others and eventually also the spectrum of autism.
If we compare the neocortex with a huge piant of a cauda, in which each key produces a note, The result is a symphony that is nothing more than the perception of reality. In the case of autistic children, there is a theory that they can perform super symphonies that a common person has no capacity to understand. Neuroscience challenges us to launch a new look and understanding about the difference.
Doing experiments on animals is that the microcircuits in the neocortex are intensely connected. That means that when input comes in, they react very strongly, they produce very complex responses, they learn very quickly. The drawback is that they don't unlearn, they don't forget. So there we found it's a very... A different way of thinking about autism is that actually the brain is hypersensitive and you could think of the world as suddenly somebody dialed up the intensity of the lights, of the colors, of the sounds, of the textures.
Autistic child taking a shower is like needles falling down on its back. And that just gave us a very different perception of... how we should be thinking about autism and then it's natural that they would avoid and not interact with people and sit in the corner and start rocking.
People with the autism spectrum disorder have increased capacity for processing visual information. They have a tendency to observe more a visual task and look at the level of detail of visual information around them. It might help in directing them to the type of jobs that involve this type of better visual inspection abilities. So if you do the X-ray scanning in an airport, it's quite important to be able to detect potential hazards among the objects, and it is possible that they would do that with a better ability.
And if we could embrace their diversity and their talents, it's of course not easy, it's difficult, but if we could, we could see even more amazing capabilities. There has been some anecdotal description of the Asperger syndrome of the Silicon Valley, and that might be again related to this Asperger syndrome people. are better suited for particular computerized tasks, such as those that are prominent in the Silicon Valley. It is evident the amount of artists and scientists with mental pathologies. It is now concluded that great references such as Newton suffered from Asperger's syndrome, a milder form of autism.
There are several entrepreneurs of reference who suffer from a disability of attention with liberality. What is considered by society as a deficiency can result in an extraordinary capacity. To be a genius, we have to be crazy? The greatest scientist who ever lived was Sir Isaac Newton. He was a genius.
He lived in a world of witchcraft, sorcery, and magic, and from that extracted the universal laws of gravitation, the universal laws of mechanics. But Isaac Newton was not a man you want to invite for dinner. He was incapable of small talk.
You couldn't simply gossip with him. He had no close friends at all. He was a loner, a loner all by himself, working out the mysteries of gravitation and the universe. Some psychologists believe that he suffered from Asperger's syndrome.
People with Asperger's tend to have very low social skills. They tend to be loners, but they have this extraordinary ability to concentrate. concentrate superior mental firepower at a specific question and work on it for years, decades at a time. Most mortals, we can't do that.
We can barely concentrate in our chair for five minutes. These individuals can concentrate for decades on a single problem. Look at Einstein. Einstein spent ten years, when he was 16 to when he was 26 years old, working on special relativity. and then another 10 years, from age 26 to 36, working out general relativity.
How many of us had that firepower to spend 20 years of your life on one single theory? What I think is wrong is to think that only people who have a considerable degree of mental pathology, for example, are capable of being great artists. Of course, from the point of view of neuroses, it is a well-made connection, but, of course, after all, we are all neurotic, fortunately, and whether we are scientists or artists or politicians or investors in the stock market, we all have a good degree of neurosis. And if we don't have a high degree of neurosis, we are extremely abhorrent and abhorrent people. In the 1800s, we had Carl Friedrich Gauss, the greatest mathematician of his era, the prince of mathematicians, and his brain was preserved after his death.
And looking at the brain, we find that it has more convolutions than the average brain, more surface area, more surface area in which to think. And Einstein's brain was also preserved at his death, against his wishes, by the way. Maybe Einstein was just born to be a genius, or maybe the constant habits that he had of concentrating superior firepower at a single point, maybe that characteristic was developed, learned over time, and that's why his brain began to change. We don't know.
All we do know is that the brains of some of the greatest mathematical and physical geniuses of the past, their brains we're different. If we have this power to concentrate superior firepower at a single point, to shut out distractions, to be able to focus on one problem for long periods of time, maybe there's a Newton, maybe there's an Einstein in all of us. Attention is an umbrella term for the fact that we have limited capacity to process information. And because we have limited capacity, we have to be selective. We can only perceive whatever we paid attention to.
We know that there are people who are especially good at paying attention to a class for an hour, and others, at the end of five minutes, I'm seeing who entered, who saw, who breathed. They are the children with a so-called lack of attention. Some of them are hyperactive, others, on the contrary, are hypoactive, they are dreamers.
Many alternate between one thing and another. Hyperactivity is a very common concept for categorization effects. When a child starts to move a lot, it can be categorized as such, although there is often no problem. We need to move to retain things better.
Physical exercise will surely improve the performance of the circuits that are working. Excessive medication in children and young people is a worrying trend in the last decades in industrialized countries. In the United States of America, in the period of 7 years, the consumption of a calming substance rose by 700%.
These are quite impressive numbers, in fact, because there are many people who take medication and who should not be taking it. The problem with the child who is distracted is not that he doesn't pay attention to anything, he pays attention to everything and doesn't concentrate on anything. We have shown that people with ADHD on one hand are indeed more destructible compared to a control group of people without ADHD. However, we have also shown that if you make the task that they are engaged in more difficult, They engage more attention and their destructibility is reduced to the same level as people without ADHD. So the message here is that instead of making the tasks easier to help people with ADHD, it is actually the opposite message.
The benefits of sleep are becoming increasingly evident for the maintenance of the entire human operating system. It is known today that during sleep an important task of cleaning toxic waste produced in the brain during the day takes place. This kind of reset is important for learning, creativity, memory consolidation and for the prevention of various devastating pathologies such as Alzheimer's, by eliminating the toxic substance associated with the disease.
Humans no longer sleep as nature planned. With the advent of the Industrial Revolution, we eliminated the basket and its benefits. In a society where sleep hours are increasingly penalized by the pressure of technologies and cities that do not sleep, it is the balance of the entire system that is at stake.
When we are badly awake, things don't go well, from memory to the hard disk. Which is in fact the serious problem of children with attention deficit. It is the difficulty in recording the things they have understood.
They understand, by definition, attention deficit, they don't have a problem of understanding, but after two minutes, it even gets badly arranged. They get to the test the next day, but we did that yesterday and everything was fine, you knew very well, but they get to the test and they don't know. One thing we know is that if we sleep, We better consolidate certain memories.
For example, if we have to solve a complex problem, there are experiences that show that a large percentage of people, after sleeping, can find the solution to the problem. So, sometimes it is said that the pillow is a good counselor, she will sleep on the problem. Many young people are taking medication, young and adolescent. I'm taking medication to keep myself awake at least in school and daily tasks, when they should be sleeping at least 8.30 or 9.00, instead of sleeping at 6.30 or 7.00. When we are younger, we need to sleep more hours.
So, it's not just more hours, but wake up later. And it's precisely at that time that we have school starting, for example, very early. So, those first hours...
I always say that they are a bit out of tune, because the brain biologically wants to sleep. results in a chain of electrical shocks that release more than 100 chemical substances in the brain. As a result of an exploratory curiosity, the human being discovered in nature substances that take over the circuits of the brain and that increase the natural sensations.
It is the case of caffeine, chocolate and drugs. turning on that system that gives you great pleasure. Of course you're going to want to want more and more of whatever worked. The problem is that as that happens, the system, because it becomes so strongly activated by these drugs so more intensely than it ever would by its own means, the system protects itself by becoming less sensitive. The consequence is that the next time that you use that same amount of that wonderful drug, the effect will not be there anymore.
It's not going to be the same. So you start going down this slippery slope of needing ever higher quantities of that drug that will, however, only get you less and less pleasure. And that is addiction.
How exactly? Those drugs work in the brain is a big mystery and something that neuroscience has been struggling to answer for 50 years or more. Serotonin is the target of many drugs so it's one of the most I would say mysterious features of our brain that it can be modulated by this molecule that can change radically our thoughts, our perceptions, our behavior. And it's still even a mystery exactly how it does that.
Teenagers are especially prone to becoming addicted to drugs because this entire system that generates pleasure in the brain is undergoing remodeling. That starts at about age 12, 13, and when this reward and motivation system naturally... every single one of us, it loses sensitivity.
The consequence of that is that typical teenager boredom. All the things that you used to do that were good, playing with dolls, just running around just for kicks, all of a sudden they're not as pleasurable anymore. And that is your brain maturing and then learning to adjust. to this new reality, which is very good because it takes you, it leads you to new pleasures.
When all of a sudden what used to be pleasurable no longer works, you find yourself seeking out new interests, new pleasures, new things to do. That is what teenage life is all about, finding new interests, new sources of pleasure. Suicide is the second biggest cause of death among young adults.
Frequently associated with suicide, depression arises, the most common psychiatric pathology in the world. One in ten people suffers from depression and in 2030 it is estimated to be the most incapacitating pathology. It is symptomatic that in the last 30 years 46,000 scientific studies have been done on depression and only 400 on happiness.
There has always been depression in a teenager, for example, or in a teenager in adulthood. Maybe a third or a quarter of people who enter adulthood, in the third of their adolescence, pass through a stone of joy in things. Before, a person who was ill would get angry and would look for other solutions, but he would not be locked in a room 24 hours a day, 6 days a week.
But this can happen to many children who are connected to the internet and they can say that they are fine. It's not simply one area. It's not simply one cluster of neurons. No, it's spread out across the entire brain.
Many parts of the brain fire when somebody suffers from depression. The first studies of a modern clinical type took place in the 1950s. It's now 60 years later, and we still are using more or less the same class of drugs, the same... ECT, electroconvulsive therapy, it's still considered an effective treatment.
There are some new drugs, but they're actually not much more effective than the original drugs that have been around for half a century. the clinical use of psychedelic drugs in microdoses has conquered ground as one of the new ways of neuroscience in the fight against depression. By causing a kind of disorder, these substances have the ability to reorganize the brain. hallucinogens or psychedelics or entheogens.
These molecules are currently being tested for use in the treatment of depression. And the initial studies show that they can have a very strong effect on a person's mood for weeks or months following a single session with a psychedelic. We honestly don't understand.
The biology underlying these molecules. One popular way of thinking about it, that actually has been around for a while, is that these are a class of compounds that facilitate change. They help the brain to reorganize itself in the face of persistent problems, adversity, or failed solutions.
And by triggering what's probably a natural response, they can help us to change. Psychedelics help the brain to repair, psychologically speaking, a bad world view or a bad way of approaching a problem. There is a theory that says that one origin of depression, sometimes leading to suicide, is the mismatch. You have the reality in your brain, and then you have the reality that you see outside. And if there's a mismatch between these two, You can become very depressed, in fact even suicidal.
But scientists who are evolutionary biologists have a theory. Have a theory, in fact, about suicide. Suicide tends to violate Darwin's theory of evolution. Darwin's theory of evolution says survival of the fittest. So why should you kill yourself and your genes simply disappear?
That seems to violate all of Darwinian evolution. However, there's a theory. It turns out that when you interview people who are suicidal, one common theme is they feel that they are a drain on their loved ones. They commit suicide because they don't want the tribe of their genes to suffer because of their individual problems. The first cause of death among young people are road accidents.
The second is suicide. The first consequence of the misuse of human technology. The second is by own will. A statement that makes us question what is wrong, what is the piece of the puzzle that is missing. There are those who defend a growing discrepancy between the evolution of the human brain and the society we build, between our biology and our culture.
Unveil the mysteries of the human brain. In the last decade, the knowledge of more than 100 types of neurons, the so-called gray matter, has advanced. Today, the importance of white matter, as vast as 160,000 km of nerve fibers, is equally recognized.
Enough to go around the Earth four times. It is undisputed the progress in the knowledge of the human brain, but at what point are we after all? We can say that the brain is, in a certain way, cartographed.
how would the world map of the 1500s look like? I imagine having a map without knowing who lives in those places, if it's inhabited or not, if it's habitable, what happens, how do you get there. So we don't know much about that.
Humans have therefore known for more than a hundred years that nerve cells are connected in a very complicated network, but... But what has happened in the last decade is that techniques to allow us to actually render and visualize this vast network have become available. We're seeing things for the first time that we knew were there in some sense, but had never actually witnessed before.
We already knew for a few centuries how the great parts of the brain are made up, then we divided the brain into areas. and at this moment we started to have a map of how the neuronal cells, the neurons, connect to each other. The kingdom of the neuron is almost over. The neuron was in fact the Nobel Prize.
of Santiago Ramón y Cajal at the beginning of the last century. But the neurons are 10% of the cells inside the brain, so it would be a bit strange if the others were not doing anything. And so today we are understanding more and more how things work, not only in the interrelation of the brain inside the cells, but with the other brain structures, but with the rest of the organism.
Over the course of the next 10 years, we're going to know much more than we now know about the... structure of the brain, that is the anatomy of the brain, and micro-detailed. At the same time, we're getting enormously increased capacity to understand the functioning of the brain using imaging techniques. And the imaging techniques change and improve almost daily in terms of what is able to be seen in the human brain that is undergoing all kinds of learning and remembering and so on. When you looked at astronomy, What made the difference was the invention of the telescope.
With your own eyes, you could see that many of the tales about the heavens were incorrect. Now, with high technology, MRI scans, computers, we can peer right into the mystery of the thinking brain. We can actually see thoughts, thoughts ricocheting back and forth inside the living brain. And so the brain is no longer a black box.
I feel very fortunate to live in a time when there is a kind of renaissance in imaging. Every aspect of imaging is undergoing very rapid evolution right now. Optogenetics, for example, you know, the ability to use light to manipulate the activity of cells, the activity of molecules in cells.
I think one of the things that will have a real impact in the next 10, 20 years is... Our ability to manipulate specific molecules in specific cells in the brain And the possibility of reading the activity of these neurons by making them emit fluorescence when they are active has also been fascinating. And it has completely changed the way we study the brain. And you may ask, why is this important?
Why do we have to bother with molecules? Maybe cells are as complex as we need to go. I think that evolution has carved in the properties of molecules working in specific cells.
So by knowing how specific molecular mechanisms are acting in specific cells and in specific circuits and in specific parts of the brain, we are going to start to unravel how evolution carved who we are. The progress we have had in terms of technology and worldwide It's really fascinating. But what we have to know is even more fascinating. Despite the fact that there is a lot of technology, we don't know basic things like how to store a memory, how to get that memory when needed, how to make a decision.
And so we also don't know what happens in compulsion, in addiction, in Parkinson's disease, in Alzheimer's disease. And so this urgency to understand... How the brain works has become a priority worldwide.
The discovery of the brain is the most frenetic and urgent race in the history of humanity, more than the fall of the Moon or the current discovery of space. but will have the human brain capacity to know itself. Since 2013, several programs of public or private funding have been launched worldwide for the investigation of the brain. The European Union launched the Human Brain Project.
The United States of America launched the Brain Initiative. China, Japan, South Korea, Canada and Australia followed. Aware of the dimension of the challenge, all these countries joined forces, creating the International Brain Initiative.
It is really exciting that the world is coming together. I think there's first the each country formed their own initiatives. Now there are actually several initiatives to bring the world together. The brain is the most complex structure that we know of.
It cannot be understood with just any one group or any one country. So a global initiative is really an exciting and important activity to help understand how the brain works. In the Human Brain project, we want to address the connected brain as a multi-level system consisting of nested nodes and connections. Brain networks are key for our understanding of brain function, cognition or consciousness. Just as the mapping of the human genome, it is hoped that the discerning of the brain is decisive for humanity.
There are several approaches in this global attempt to map the totality of neurons and synapses from the animal study or from the human brain itself. Simulating the brain electronically, recreating neuron by neuron. the most complex machine in the universe, with supercomputers capable of quadrillions of calculations per second, or create a global platform for sharing knowledge, unlocking the doors of the brain to the whole world. One distinguishing feature that the HPP has is that we want not only to understand and analyze the human brain, but we would like to build a research infrastructure, so that the knowledge that we are generating is not only for us or our researchers. But we would like to provide a lasting contribution to research by providing tools and services, supercomputer, infrastructure, simulation engines, and so on and so forth, that then make a difference in the next years.
Projects like this are very much needed. Projects that integrate all of this information and place it in formats that people like mine can navigate it more easily are going to be... absolutely central to our ability to understand the inner human brain.
In the Blue Brain Project we're trying to understand the structural design of the brain and how the structure gives rise to function. Our approach to it is to reconstruct it digitally and then simulate it. It means that as you're learning how to map the brain, you actually are solving some very fundamental questions about The kinds of neurons that are in the brain, how they're organized, how they connect with each other, where the molecules are located, why they're located in certain places.
We can begin to understand the correlates, the neuronal correlates with higher brain functions, like actions, decisions, memory, perception, and so on. We have no better way of thinking about our own brain than... to think about how it is that we would actually build one. As we move forward in several fronts in the decoding of the brain, a question arises.
How far are we from the mapping of the human brain? Well, I think that on the current resources, we will have a full mouse brain reconstruction within the next couple of years. It could be 2024, 2028, and we'll have the beginning of the human brain reconstructed also by that. So the question how far we are away from the complete mapping depends on how detailed would you like to go.
So when you think about a map of the Earth, of our planet, then we can have maps which show the political subdivision of the Earth. So which countries, which states are there. but you can go into more detail. So you have political maps, you have maps about the distribution of temperature, you have maps characterizing how the nature is, where is forest, where is sea and so on.
And this can be really transferred also to our concept of a human brain atlas. If the digital reconstruction of a brain cell of a mouse with 31,000 neurons and 8 million synapses was revealed a complex mission, It's easy to understand the size of Hercules in front of a terrifying human brain with 86 billion neurons and 100 trillion synapses. One of the great challenges scientists face is the extreme complexity of data. The information contained in a brain of the size of a grain of salt is equivalent to 25,000 high-definition films. We know that worms can have maybe several hundred neurons in its nervous system and they're fruit flying.
Its brain was analyzed, sliced up, analyzed, and we now know the fruit fly has a hundred thousand neurons, and we even know how they're hooked up. So think about that, a hundred thousand neurons in an insect that can maneuver like this, evade danger, find food, find mates, hide. Amazing! A cubic millimeter of brain, which is about a millionth of a human brain and maybe a thousandth, of a mouse brain is about 2,000 terabytes of data and a terabyte is already a very large data set. 2,000 terabytes is two petabytes.
If one wanted to do the whole brain of an animal like a mouse, which is something we are trying to envision how to do, one's dealing now with something called an exabyte of data, which is about a thousand petabytes, or a million terabytes, or really a trillion megabytes. So it's impossibly large to deal with. And these datasets are getting to the point where they compete with the entire digital content of the world.
It's like Google Earth but in layers, where you don't only have the surface of the Earth, but layer after layer after layer, thousands and thousands of layers, as you go deeper and deeper into the brain as opposed to the planet. I think in the long run what this means is that the dataset will be shareable. It will be very much like a Google Earth dataset. Where people can go in and trace a pathway from one part of the data set to another, very much like you can get a directions to get from one street to another address in Google Earth.
But now it's a three-dimensional data set. It's spectacularly beautiful and interesting to look at. Human brain can no longer understand itself by itself.
I mean, think of economy, for example. Our economy is not run by economists anymore. I don't know if you... If you realize this, our economy is run by computers that make trillions of transactions every microsecond around the world.
Trying to systematize the behaviors of millions of millions of neurons and trillions of synapses will not be an impossible task. We will not be attributing rules to a kind of abstract art. No, the brain is a deterministic machine.
And even if every individual, the connections are slightly different, there are fundamental principles that decide that this type of cell will connect with so many of that type of cell and so on. So there's a lot of rules. If there weren't rules in the brain, you would never be able to keep such a complex system stable. It's actually remarkable that the brain is so stable.
The secret of biology is that very simple principles can generate Enormous unthinkable complexity. So I think as we strive to understand how the brain is put together and how the brain functions in individuals like you and I, I think that we're going to find a series of these very simple principles that are behind all of this complexity. Nature is simple.
It's just that we need to find them.