Limbic system: the emotional part of the brain

The limbic system is one of the most interesting and important neuron networks when studying human behavior, since it is one of the parts of the brain with a more relevant role in the appearance of moods.

That is why it is sometimes called "the emotional brain." But... What exactly is the limbic system and what are its functions?

What is the limbic system?

The limbic system is a set of structures of the brain with diffuse boundaries that are specially connected to each other and whose function has to do with the appearance of emotional states or with what can be understood by "instincts", if we use this concept in its most large. The afraid, the happiness wave Rageas well as all nuanced emotional states, have their main neurological basis in this network of neurons.

Thus, at the core of the limbic system's utility are the emotions, that which we link with the irrational. However, the consequences of what happens in the limbic system affect many processes that, theoretically, we do not have to associate with the emotional face of the human being, such as memorization and learning.

The limbic system in learning

More than 200 years ago, an English philosopher named Jeremy bentham, one of the parents of utilitarianism, he proposed the idea of ​​a way to calculate happiness based on a classification of criteria to differentiate pain from pleasure. In theory, from this calculation we could know how useful or not very useful each situation, depending on how happy it made us according to this formula.

Simplifying a lot, it can be said that, in a way similar to that proposed by Bentham, the limbic system is something like the judge who determines what deserves to be learned and in what way it has to be memorized depending on the pleasant or painful sensations that each situation produces.

In other words, the way in which the positive or negative value of each of the experiences that is lived depends on the limbic system. But, in addition, the way in which the limbic system influences our way of learning will have repercussions on our personality.

Some examples

For example, a mouse that has passed through operant conditioning and has come to associate the action of moving a lever with the appearance of food in a drawer of his cage, he learns that moving the lever is fine thanks to the pleasant sensations that it It produces seeing food and tasting it, that is, based on something based on the euphoria of discovering a piece of cheese when hungry and on the pleasant sensations it produces eat it.

In humans, too it can be understood that those situations in which pleasure is more sublimated in a complex way, like what it feels like to listen to a good poetry recital, she teaches us that going back to the cultural association in which we have heard it is "useful". The limbic system is still the part of the brain responsible for this.

The parts of the limbic system

It should be remembered that the limbic system is not exactly an anatomically exact region of the brain, but rather is a neuron network distributed throughout the brain and mixed between many different structures. In other words, the concept of the limbic system has more to do with the function of these areas than with their nature as a specific and well-defined part of the brain.

However, it is possible to point out parts of the brain that play a very important role within the network of interconnections. which is the limbic system and that, therefore, they serve to give us an idea about which are the areas through which this circuit. The parts of the limbic system are as follows:

Hypothalamus

One of the areas of the diencephalon most involved in the regulation of emotions, due to its connection with the pituitary gland and therefore with the endocrine system and all parts of the body in which all kinds of hormones are released.

• To read more about this part of the brain you can read this article on the thalamus

Hippocampus

The hippocampus plays a very important role in memory-related mental processes, both in the memorization of experiences and abstract information and in the recovery of memories. The hippocampi are located on the inside of the temporal lobes, very close to the thalamus and the tonsils.

The hippocampus is framed within what is known as the limbic lobe cortex, or archicortex, which is one of the oldest parts of the cerebral cortex; In other words, it appeared very early in the line of evolution that led to the appearance of the human being.

Amygdala

The brain tonsils are located next to each hippocampus, and therefore there is one in each of the hemispheres of the brain. Its role is related to the learned emotional response that certain situations arouse, and therefore therefore they are involved with emotional learning, for which they have a role in the system limbic.

Orbitofrontal cortex

At the limits of the limbic system is the orbitofrontal cortex, which is the outlet valve for "emotional" orders to areas of the frontal lobe in charge of planning and creating strategies. Therefore, plays an important role in quelling the "irrational impulses" that come from the limbic system and pass only part of these signals, those that will serve to define well the objectives of the actions with medium or long-term goals.

Is it correct to speak of an "emotional brain"?

In popular culture there is a widespread idea that the human brain has an emotional and a rational part. The emotional brain, which we would have inherited from our most primitive ancestors, would be the one thanks to which we have emotions, feelings and impulses difficult to repress, while the rational would be in charge of the most conscientious and logical analysis of the situations we live or we imagine.

However, as we have seen, the limbic system is deeply interconnected with other areas of the brain not directly. identified with what we know as emotions, so the idea that we have an emotional brain is, to a large extent, an overly imaginative way of understanding this network of connections.

In addition, it must be borne in mind that if we speak of an emotional brain it is to contrast this concept with the idea of ​​a rational brain, which would be represented by the most superficial areas of the frontal lobe and the parietal. However, if in the case of the limbic system at least we know that it is a set of quite old structures in our line evolutionary, the idea that there is in us a part of our body made to think rationally with a certain autonomy is directly a delusion.

Rationality is not innate

There are ancestors of ours who lived only with a limbic system and without the ability to think following the guidelines of what we understand as rationality, but in the history of the human being rational thought is rather an exception. Not only do we not think rationally most of the time, but until a few thousand years ago the rationality did not exist and, in fact, in some cultures that are not very Westernized, adults tend not to the fourth stage of cognitive development proposed by Jean piaget.

In other words, what we call rationality is more a product of history than the fruit of a set of brain structures designed for it. The limbic system is, in any case, one of the regions of the brain that allow the appearance of rational thought, and not the other way around.

Bibliographic references:

• Herculano-Houzel, S. (2009). The Human Brain in Numbers: A Linearly Scaled-up Primate Brain. Hum Neurosci.
• Maton, Anthea; Jean Hopkins; Charles William McLaughlin; Susan Johnson; Maryanna Quon Warner; David LaHart; Jill D. Wright (1993). Human Biology and Health. Englewood Cliffs, New Jersey, USA: Prentice Hall.
• Rosenberger, Peter B. MD; Adams, Heather R. PhD. Big Brain / Smart Brain. December 17, 2011.