How does the brain store memory?
Our ability to remember helps us thrive throughout evolution. Imagine if you wonât be able to remember what happened yesterday. In that case, you will be frozen in time.
But forgetting is a simple mechanism that keeps our brain able to absorb new learning. It keeps us safe from having trouble with too many information we come across on a daily basis. Thus, forgetting has a very important role in keeping the brainâs healthy functioning.
But how exactly does the brain store memory?
It is long been debated whether or not the human brain stores memory as computers do. But the human brain, according to neuroscience, works far different from a computer. The human brain holds new information temporarily before it becomes permanent.
Every learning will be stored as a short term memory. This is because that information would only exist in a short period of time. In contrast, long term memories are virtually permanent.
But how the brain turns short term memories into long term memories?
Okay, hereâs the thing. All learnings will be temporarily stored in the short term memory. The fate of that pieces of information depends on the neural connections. Theoretically, the stronger the neural connection, the better the consolidation.
Consolidation is a neural process that converts short term memories into the long term. Memories that remain in the short term state tend to vanish almost immediately. While long term memories remain retrievable and can easily be remembered.
But how consolidation works?
Short term memories are believed to be stored in the hippocampus. This tiny part of the brain is responsible for serving as temporary storage of all newly learned information. Then the consolidation takes place.
As mentioned, consolidation involves creating and/or strengthening neural connections to make short term memories more stable. How? Through repetition.
Thatâs right. This seems a tedious process but it just the way it works as far as currently available pieces of evidence suggest. Repetition makes stronger neural connections which in turn transform short term memories into the long term.
Repetition seems to be the best way to develop a memory readily available for retrieval. In other words, if you want to remember an important piece of information, you need to stimulate it over and over again.
This is the main reason why I suggest to most of my students to study at least two weeks before the exam. The reason being is that such duration allows the brain to consolidate most information that the students want to remember during the exam.
Applying the repetition rule, therefore, students should develop a steady and consistent study habit to constantly activate the neural connections that hold the information. In this way, the information may become stable and less likely to be forgotten.
Why cramming is useless?
The simple reason why most students who cram donât usually succeed in their academic endeavors is that they donât really understand how does the brain store memory. As a result, they tend to multitask. They multitask because they ran out of time.
But hereâs the problem. The brain not only needs a sufficient amount of time to encode and consolidate the information, but it is also incapable of attending multiple tasks. It only causes information overload. So cramming or multitasking is both useless and detrimental to cognitive functioning.
So if you want to remember most of the information (if you are a student) try to study longer. Use your downtime to read your notes and books. This sounds laborious but this is the only way towards academic success.
Where does the brain store long term memories?
So far, weâve talked about hippocampus. What about the long term memory? Where does the brain stores long term memory? This is actually a more complicated question. And as you might have already noticed in other scientific sources, there is no single answer to this.
Classic studies on memory show that, unlike the short term memory, long term memories are distributed and stored in different areas of the cortex. This assumption was popularized by early neurological researchers Karl Lashley and Wilder Penfield in the 1950s and 1960s.
As soon as short term memory transformed into long term, it will be distributed to the different parts of the cerebral cortex for encoding. The groups of similar neural connections are formed and behave similarly. In other words, if similar experience occurs, those groups of neurons that contain the memory of such experience will fire together.
A quick note. Firing means that a group of neurons is activated. The activated neurons release neurotransmitters as means of their communication.
Long term memories are encoded multiple times creating more duplicates or memory traces (engram) so that if one engram is lost, multiple pathways remain to make the memory still retrievable.
Why we forget things we donât want to forget?
We all want to have a sharp memory to remember all the significant information we want to retain. But most of the time, we tend to forget many of our experiences. If I ask you how much information you can still remember as you scroll down this page, thereâs a high possibility that you forget most of the things you have read.
Most experts believe that forgetting is a result of inaccuracy in the encoding process. Memories that are incompletely stored will be most likely forgotten. Are forgotten memories lost forever? Well, that may not be the case. Some experiences, in your past, for instance, are totally inaccessible for a moment but you may recall them later. Therefore, the memories are still there but the cues that could bring them to the surface of your awareness do not match. As a result, you are unable to retrieve them.
Can forgotten memories be retrieved?
Sigmund Freud the founder of Psychoanalysis believed that there are three divisions of the mind: consciousness, preconsciousness, and unconsciousness. Consciousness is the smallest of the three. It only holds the things that are readily available for retrieval.
The preconscious mind stores the memories or experiences that are not currently available for retrieval but are not totally forgotten. This region of the mind contains materials that are waiting to be primed. For instance, suppose that you forget the word âdiskâ but then when you heard the word dish, you suddenly remember the former.
The unconscious mind is the biggest of the three. According to Freud, the unconsciousness contains all the suppressed emotions and experiences. It includes all the memories in your childhood that you might have already forgotten for years. But Freud believed that memories stored in unconsciousness are retrievable. Through hypnosis (a method being used in psychotherapy) forgotten experiences can be retrieved.
However, some argued that hypnosis can be inaccurate. In fact, some suggest that the so-called memories retrieved through hypnosis might have been the effect of the treatment.
But one thing is certain though. The brainâs ability to store memory declines with age. The neurons, especially those in the hippocampus area lose the connections that previously held the information. This is the reason why older adults have difficulties remembering.