How the human brain works, in 8 keys

A practical summary to understand some basic principles of our brain.

Understanding how the brain works requires years of learning, and despite this, the level of understanding that we can have about this set of organs will always be very limited; not in vain the human brain is one of the most complex systems in existence.

On the other hand, there are some ideas that help to begin to better understand this tangle of concepts that serve to explain what this organ is. that serve to explain what this part of the nervous system is. These are some of these keys.

Basic ideas about how the brain works

This is a list of ideas a list of ideas that I believe help to understand the fundamental ideas about how the brain works.. I recommend reading them in order, because they are ordered from the micro to the macro.

1. Glia and neurons

A brain is, fundamentally, a collection of neurons and glial cells. The latter are less well known outside of universities, but are actually much more numerous than neurons (which is quite impressive, considering that an adult human brain has about 80,000,000,000,000 neurons).

What is each of these cell types responsible for? Neurons are the ones that create the electrochemical signal flows that constitute mental processes; basically, everything that psychology studies is embodied in the way neurons communicate with each other.

Glial cells, on the other hand, have very diverse functions, and until recently it was believed that they were basically responsible for protecting neurons and facilitating their movement. However, in recent years, research has shown how glial cells have their own communication network and can influence how neurons relate to each other. In other words, we are just beginning to fully understand their importance.

2. The role of synapses

When it comes to understanding how the brain works, knowing how the communication networks between neurons function matters as much or more than knowing how each neuron works individually, and that means that the points at which these nerve cells send information to each other are of crucial importance to neuroscientists and psychologists. The name given to these areas is the "synaptic space," which in the vast majority of cases is a small gap that opens up between the neurons. is a small gap that opens up between the cell membranes of the nerve terminals of two neurons.One of them is the presynaptic and the other is the postsynaptic.

At synapses, the electrical signal that travels through a neuron is transformed into a chemical signal, i.e. a stream of substances that we call neurotransmitters and neuromodulators. These microscopic particles reach the nerve terminal of the other neuron and there, they are captured by structures called receptors. From that point on, the torrent of chemicals received by the post-synaptic neuron has an effect on the frequency with which this nerve cell will emit electrical impulses that can have an effect on other neurons.

This mechanism seems simple, but it really is not, because there are many types of neurotransmitters and structures that interact with them, and at the same time each neuron is usually connected to many others at the same time: information is not usually passed in a linear fashion, as in the game of telephone.

3. Software and hardware are indistinguishable

It is common to try to understand the brain as if it were a conventional computer, but this comparison is only justified in certain contexts, because it does not serve to capture the real functioning of the brain. And one of the main reasons why a brain differs from a computer is the fact that in the former it makes no sense to distinguish between software and hardware. All the processes that are taking place in a brain materially modify the brain, and the structure of the brain itself is the same as that of a computer. the structure of the brain itself is what makes neurons send nerve signals to each other: it does not depend on programming codes.It does not depend on programming codes.

That is why, among other things, the brain does not work with contents that can be stored on a USB stick, as is the case with computers. We can play at interpreting what is going on in a brain in real time, and have this interpretation structured as a code that is understandable to us, but that code will have been invented by us; it does not emerge from the brain. This does not mean that it is impossible to know in an approximate way what certain parts of the torrent of information that travels through a brain consist of.

4. Brain plasticity

From what has been said above, we derive this other idea: that the brain is changing all the time, no matter what we do.. Everything we perceive and do leaves a more or less intense mark in our brain, and this mark, in turn, will cause all those that occur from that moment to be of one form or another. In other words, our mental life is an accumulation of modifications, of neurons that tighten their bonds and then loosen them according to everything that happens to us.

This ability (or, rather, need) of our brain to constantly change depending on circumstances is called brain plasticity.

5. The role of attention

As much as the human brain seems to be a natural prodigy capable of doing quite impressive things, the truth is that the set of data it works with is always full of gaps. In fact, it is not even capable of properly processing all the information that comes to it in real time through the senses, let alone remembering it all, something that only happens in incredibly rare cases.

What the human brain does is to obey the survival principleWhat matters is not to know everything, but to know just enough to survive. Attention is the mechanism by which certain parts of the available information are selected and others are ignored. In this way, the nervous system is able to locate elements of information that are relevant to focus attention on them and not on others, all depending on what our objective is. This mechanism is very useful, because in certain circumstances we seem to be blind to things that happen in front of our noses.

6. The brain invents things

This point is derived from the previous section. As the brain has a limited amount of "processable" information, there are some information gaps that it has to fill in without us constantly having to look for the missing information. To do this, there are some automatic mechanisms that cover up the missing information, there are some automatic mechanisms that fill these gaps in a discrete way..

An example is what happens with the part of the retina that gives way to the beginning of the optic nerve. This is an area in which the eye is unable to transform light signals into nerve impulses, and therefore it is as if we have a hole in the middle of our visual field. However, we are not aware of this.

7. The parts of the brain always work together

Although the brain is made up of different anatomical areas more or less specialized in some processes, all of them need to be well connected with each other, all of them need to be well connected to each other to do their job well.. This does not mean that they all have to communicate directly with each other, but that in order to function they have to be wired with the "general network" of information that circulates through the brain.

8. The rational and the emotional go hand in hand

Although it is very useful for us to distinguish between the rational and the emotional in theoretical terms**, in our brain all the mental processes that we can link to one or the other domain work together**.

For example, the parts of the brain most related to the appearance of emotions (a set of structures known as the limbic system) are the ones that set the objectives that we try to achieve effectively through action plans based on logic and that, in any case, will not stop being influenced by emotional factors that will make the rationality of these strategies quite relative, even if we do not realize it.