Hippocampus: Functions And Structure Of The Memory Organ
He hippocampus It is one of the most important parts of the brain.
It is located in what is known as the limbic system, and is closely related to both mental processes related to memory and those that have to do with the production and regulation of emotional states, in addition to intervening in spatial navigation, that is, , the way in which we imagine movement through a specific space.
The etymology of the term “hippocampus”, a word coined by the anatomist Giulio Cesare Aranzio, refers to the similarity between this brain structure and a seahorse. Is about a small organ with a curved and elongated shape, located in the inner part of the temporal lobe and goes from the hypothalamus to the amygdala. Therefore, each brain has two hippocampi: one in each hemisphere of the brain.
In addition, the hippocampus is associated with a part of the cerebral cortex known as the archicortex, which is one of the most ancestral regions of the human brain; That is, it appeared many millions of years ago in our evolutionary line. That is why the hippocampus is so well connected to other parts of the limbic system, which appeared to provide answers to some of the most basic needs of our most remote mammalian ancestors. In turn, this fact already allows us to intuit that mental processes related to emotions are linked to the functions of the hippocampus. Let’s see what they are.
The main function of the hippocampus is to mediate the generation and retrieval of memories. in conjunction with many areas distributed throughout the cortex and with other areas of the limbic system.
Therefore, it has a very important role in the consolidation of the learning carried out, since on the one hand it allows certain information to pass into long-term memory and on the other it links this type of content with certain positive or negative values, depending on whether these memories have been associated with pleasant or painful experiences (physiologically or psychologically).
Are mental processes linked to emotion those that determine whether the value of an experience stored as a memory is positive or negative. What we experience as emotions has a functional part that has to do with the way in which we learn to behave following learned rules that work in our favor: avoid repeating mistakes and re-experience pleasant sensations.
The hippocampus and memory
One might think that The hippocampus is the part of the brain where long-term memories are stored However, reality is more complex than this idea.
The relationship between the hippocampus and long-term memories is not so direct: This organ acts as a mediator, or directory, of memories, whose appearance and disappearance is associated, from what is known about the functioning of memory, to the activation and deactivation of networks of neurons distributed throughout many areas of the brain. In other words, the hippocampus does not “contain” memories, but rather acts as an activation node that allows different memories distributed throughout different parts of the brain to be activated.
Furthermore, the hippocampus is more related to some types of memory than others. Specifically, plays a role in declarative memory management, that is, one whose contents can be expressed verbally; However, non-declarative memory, which is involved in memorizing movement patterns and motor skills (such as dancing or cycling), is rather regulated by structures such as the basal ganglia and the cerebellum.
It is known that a lesion in this area of the brain usually produces anterograde and retrograde amnesia in the production and evocation of memories related to declarative memory, but non-declarative memory is usually preserved. A person with a severely damaged hippocampus can still learn, for example, manual skills (although they would not remember having learned this process).
The hippocampus in spatial navigation
From what is known about the hippocampus, This brain structure also seems to intervene in the way we perceive space that is, the way in which we keep in mind a three-dimensional space through which we move, taking into account its volumes and references.
In fact, a type of neurons called place cells have been discovered within the hippocampus, which you can read more about in this article.
The hippocampus under disease
The region of the hippocampal formation is one of the first areas in which diseases such as dementia or Alzheimer’s This is why people who begin to experience this disease see how their abilities to form new memories or remember more or less recent autobiographical information are diminished.
However, although the hippocampus is greatly damaged, Normally the oldest and most relevant memories about a person’s life take a long time to disappear which could mean that over time the oldest and most relevant memories become increasingly “independent” of the hippocampus.
