The human brain has been described as the most complex system in existence, but that doesn’t stop neuroscientists and engineers from dreaming of fully understanding how it works. In fact, some of them have even proposed to create a digital reproduction of the human brain in order to carry out research with it that would be impossible to carry out through observation and experimentation with a real functioning nervous system.

This is precisely the objective of the Blue Brain Project, an incredibly ambitious initiative that was launched in 2005, promoted by IBM and a Swiss university (École Polytecnique Fédérale de Lausanne, or EPFL).

What has been done so far at IBM

For more than ten years, the Blue Brain Project has been building a computer model containing information about the structure and functioning of a small part of a rat’s brain. This digital reconstruction, which today corresponds to little more than a third of a cubic millimetre of tissue, aims to faithfully reproduce the way in which nerve cells connect and activate each other and even the way in which these activation patterns cause the brain to physically change over time due to brain plasticity.

In addition to covering many other areas of the brain, the Blue Brain Project has to make the qualitative leap from digitally reconstructing a rat’s brain to doing the same with the much larger and more complex human brain .

What could this digital brain be for?

The goal of the Blue Brain Project is ultimately to create a computer model that can predict to some degree how an area of neural tissue will be activated if stimulated in a certain way . In other words, the aim is to create a tool that allows us to test hypotheses and try to repeat multiple times all kinds of experiments carried out with real brains to see if the results obtained are solid and not the result of chance.

The potential of this project could be enormous, according to its promoters, since the existence of a digital reconstruction of large extensions of neurons would make it possible to obtain a “test dummy” in which to experiment with all kinds of different situations and variables that would affect the way in which the nerve cells in a human brain are activated.

This model could, for example, study how all kinds of cognitive processes work, such as our way of evoking memories or imagining plans of action, and it could also predict what kind of symptoms would produce an injury in certain areas of the cerebral cortex. But it could also help to solve one of the great mysteries of the human brain: how consciousness, the subjective experience of what we live, emerges.

Studying Consciousness

The idea that consciousness arises from the coordinated work of large networks of neurons distributed throughout the brain, rather than depending on a well-defined structure hidden somewhere in the central nervous system, is in very good health. This means that many neuroscientists believe that in order to understand the nature of consciousness it is important to look at the synchronised activation patterns of many thousands of neurons at once , rather than studying separate anatomical structures of the brain.

The Blue Brain Project would precisely allow us to observe and intervene in real time on the activation patterns of many neural networks , something that can only be done in a very limited way with real brains, and see, for example, what changes occur when someone goes from being awake to sleeping without dreaming, and what happens when consciousness returns in the form of dreams during the REM phase.

The drawbacks of the Blue Brain Project

It is estimated that a human brain contains about 100 billion neurons. To this we have to add that the functioning of the nervous system is explained more by how the neurons interact with each other than by their quantity, which can vary greatly without affecting the global functioning of the brain, and therefore what is relevant are the thousands of synaptic connections that each neuron can establish with the others. In each synaptic connection between two neurons, moreover, there are millions of neurotransmitters that are released continuously . This means that faithfully recreating a human brain is an impossible task, regardless of the number of years dedicated to this undertaking.

The creators of the Blue Brain Project have to fill these gaps by simplifying the operation of your digital brain. What they do, fundamentally, is to study the functioning of a small part of the brain of several rats (information gathered over twenty years) and “condense” this information to develop an algorithm made to predict the activation patterns of these nerve cells. Once this was done with a group of 1,000 neurons, the researchers used this algorithm again to recreate 31,000 neurons being activated in the same way.

The fact that it has been so simplified in the construction of this provisional model and that the same will be done with the human brain that is to be recreated has caused many voices to be raised against this expensive and slow-developing project. Some neuroscientists believe that the idea of recreating a brain digitally is absurd , since the nervous system does not work with a binary language nor with a predefined programming language. Others simply say that the costs are too high for the performance that can be extracted from the project. Time will tell if the Blue Brain Project initiative will bear the fruits that were expected from it.