The hippocampus is one of the oldest parts of the brain; it is believed to have been functioning in our ancestors for hundreds of millions of years. It’s a biological structure known to be highly involved in the functioning of memory. Our own individual identity, as well as our ability to learn, depends on it.

The hippocampal formation, which is the region formed by the hippocampus and a series of adjacent structures, is not functionally homogeneous; it has several parts that deal with different things. The subicle is one of them , and it has a very special role in the functioning of memory, as it has been recently discovered.

What is the sub-item?

The subículo is a part of the brain located in the lower part of the hippocampal formation , with one of the latter in each of the cerebral hemispheres. It is mainly formed by grey matter, given that in this anatomical region the somas of neurons that connect with neural structures such as the amygdala or the hypothalamus are grouped together.

Its functions

Although not much is known yet about the exact functioning of the sub-version, it is generally associated with two functions: the memory system’s own memory processing involving different parts of the brain, and the processing of spatial and motion information, related to the space occupied by objects at a given time.
In addition, it is believed to play an important role in epileptic seizures.

Your memory performance

Until a few years ago, it was believed that human memory worked as follows. When an experience is experienced, a representation of it is “recorded” by the networks of neurons that form the hippocampus. This brain structure would make it possible to process this experience by short-term memory; that is, when we remember this information minutes, hours or a few days after having memorized it, the hippocampus would be the brain part that recovers the data .

However, over time that memory moves from short-term to long-term memory, and with this transition would also come a “migration” of the data stored in the brain: they would move from the hippocampus to other parts of the brain, distributed among the frontal, temporal and parietal lobes of each hemisphere.

A few years ago, however, it was discovered that this is not how memory works, and that the sublicle plays a very important role in it.

The sub-item as a short-term memory store

As recent studies have shown with techniques to illuminate in real time the parts of the brain most activated in each moment, when we live a new experience, its memory passes from the hippocampus to one or two parts of the brain. It is “archived” in two copies that work in parallel, with a relative independence from each other. The short-term memory is stored in the subicle , and the long-term memory remains in the frontal lobe cortex, but remains “deactivated”, latent.

In the beginning, it is the copy of the memory stored in the sublicle that makes us capable of evoking those experiences shortly after having lived them. However, as days go by this copy disappears, and the memory stored in the front part of the brain’s cortex is activated.

Thus, this process establishes that the operation of memory processing follows two distinct routes , rather than following a sequence in which the memory physically travels from one particular place in the brain to another. There is a part of the memory that remains silent and that, only if certain conditions are met, manifests itself.

Parts of the sub-article

The sub-item can be divided into several structures . They are as follows.

1. Presubicle

This is the area where information from the hippocampus comes in. It is linked to memory and movement processing .

2. Postsubicle

This part of the subulle contains neurons responsible for the face being focused in a certain direction , allowing their location to correspond with certain objectives.

3. Parasubicle

This part of the brain contains network cells, which are neurons that are activated when we perceive certain movements and register them as such.

4. Prosubicle

Little is known about this region, although it has been seen to play a role in the appearance of anosognosia in cases of Alzheimer’s disease . Furthermore, in this area of the brain the neurons are somewhat smaller and distributed in a more compact and dense formation than in most other similar regions.