Often when we talk about what we remember or what we don’t remember, we are not talking about general knowledge about the world, but about ourselves and our experiences. In this case, we are the main experts, and we cannot speak of having more or less culture to know more or less details about our lives, because we decide which parts are relevant and which are not.
This type of memory based on the memories of our lives is episodic memory, And our brain has a system of nerve cells that specializes in keeping it functioning, which produces curious phenomena. Below we will see what are the characteristics of this mental ability.
What is episodic memory?
The so-called episodic memory is the type of memory responsible for processing and storing autobiographical information of each and, in particular, that facet of one’s own experiences which can be expressed in words or images. In other words, it is the set of higher psychological processes that create narrative memories about one’s own life, what happened.
Childhood memories are a typical example of declarative memory, as they are made up of short stories, first-person anecdotes and are linked to information about contexts we went through.
Thus, episodic memory is made up of data relating to a place and a time located at a given moment in our past, whether these memories are more precise or more vague.
On the other hand, and contrary to what has come for decades to defend itself from the psychological currents linked to psychoanalysis, these memories are almost always conscious (And therefore limited), although sometimes, if the imprint they left is very small, they may disappear for a while only to reappear timidly afterwards, although in no case do they come back with all the luxury of detail. or by a cathartic phase; the case of false memories instilled by another person is different, because they do not correspond to something that actually happened.
Distinguish it from emotional memory
It should be noted that episodic memory overlaps a lot with another type of memory which, although working alongside the first, is governed by different logics: emotional memory.
This set of mental processes is responsible for leave an emotional imprint linked to past experiencesIn other words, something that cannot be expressed in words.
For example, when we smell something that reminds us of our youth in a small town, this information goes beyond words and what can be told and passed on to others; after all, it is made up of subjective emotions. We can tell stories about the things we experience in this place, but we cannot infect emotions in such a direct way, just an approximation.
In short, emotional memory is not part of the so-called “declarative memory” category, made up of semantics and episodic, and is therefore not made up of concepts.
Parts of the brain involved
Perhaps the two most important brain structures in the functioning of episodic memory are the hippocampus and the cerebral cortex, particularly that found in the temporal lobes.
The hippocampi (since there is one in each hemisphere of the brain) are structures located inside the temporal lobes, and are believed to act as a “repository” of information. Which means they encode memories belonging to declarative memory, And then they let them migrate to other areas of the brain, distributed over almost the entire cerebral cortex, where they are “stored” (the role of the prefrontal cortex is particularly important).
In comparison, for example, emotional memory depends much more on another pair of structures called tonsils, and not so much on the seahorses. This way, people with damaged hippocampus remember very little about their life and yet preserve emotional responses to certain stimuli linked to their past: a house, a song, etc.
Disorders that damage it
As the memories of episodic memory are spread over a large part of the brain, there are many pathologies and types of accidents that can damage it. In practice, dementias are the most severe, eroding this mental capacity (along with other types of memory). The case of Alzheimer’s disease is known precisely because autobiographical memories are lost as the pathology progresses.
Other diseases that can cause damage are brain tumors, cerebral ischemia, encephalitis in some of its varieties and a large number of serious neurological disorders, such as Korsakoff’s syndrome or spongiform encephalopathies that pierce the tissues of the brain. the nervous system.