Memory: How long & short term memory works
We remember the same experiences differently. Every person takes in events differently, their brain processes and stores them in a different way. Why is that and how does our memory work?
Memory has fascinating characteristics. The structure of our memories is as diverse as life itself: Learned things, shapes, colours, tastes, events, feelings - both physical and emotional. For example, the feeling of being in love for the first time or the first kiss, the steps of a dance class or the pattern of a picture. Psychologists distinguish between four main memory areas:
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Procedural memory includes mechanical procedures,for example, writing on a keyboard or driving a car. These procedures run automatically, so to speak, without us thinking about them.
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Perceptual memory ensures that we recognise patterns or basic features; for example, in the case of a person who has changed visually and unexpectedly wears a beard and long hair when we meet again.
These two forms of memory run unconsciously without us noticing the memory performance.
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Our semantic memory refers to everything we have learned in our lives: At school, but also life experience in general.
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Then we remember our autobiographicaldata; who we are in the sense of our biography. Unpleasant as well as pleasant events, this also includes calendar-related dates such as birthdays, name days or wedding anniversaries. This is called episodic memory.
We remember some things easily, but we have to 'search' for other memories. Why is that?
Context and emotions play a big role in remembering
Surely you also have the experience that you think you remember better everything that is connected with strong emotions. It could burn itself deeper into our episodic long-term memory through intensity. The limbic system is our most rudimentary brain area and is closely linked to strong emotions and smells.
Without being consciously perceived, certain smells cause memories to emerge. The amygdala, along with the hippocampus, is part of this limbic system that filters all the information that enters our memory. Right next to the amygdala is the so-called olfactory brain. Smells have a direct effect on our emotions. Our ability to remember events or learning content has been shown to be highest when the amygdala and "olfactory brain" were activated together. When learning consciously, it is therefore advisable to change the context; for example, to sit on the terrace, the balcony or in a café, where the olfactory perceptions are constantly changing. We can learn at any age. Our nervous system, like that of songbirds, is designed to make new synaptic connections throughout life, and our perception of the environment is not even interrupted during sleep.
What does the brain do when it memorises and remembers?
When we remember something, something changes physiologically in our brain. Protein structures have an influence on the interconnections between the nerve cells. This creates an interaction that shapes so-called patterns. Unlike a computer, which can only distinguish between 0 and 1 in the smallest memory cells - current flows or does not flow - the protein structures in our brains are as unique as each drop of water. The patterns on the hard disk are always the same and can be read with any suitable programme. But because we learn individually, so are the structures in our brains. So whatever we have learned - even if it is that 2+3=5 - we have learned in a completely different context. This knowledge of "my five" is different from "your five" because episodic memory is also involved in every learning or memory process; that is, using the arithmetic example, the experiences and sensations that the individual had at that point in time during school. That is why music or smell can also evoke a memory. Suddenly something comes to mind and we see it vividly in front of us. The brain has wired itself in a unique way.
Memories are building blocks of our identity
If we can no longer remember something, this has a strong influence on our self-image and thus our identity. This is particularly the case with the loss of biographical data, as is symptomatic in Alzheimer's disease, because this is what makes up our individuality. How can we relate to others if we no longer know what makes us who we are? Do others perceive this as a loss of personality?
The loss of biographical memory is therefore a more serious experience than not being able to remember certain factual knowledge, such as the capital of a country, which belongs to semantic memory. "We are our memory" applies much more strongly to us humans than to other animal creatures, because our memory functions in three temporal directions: the past, the present and the future. Thus, we remember the personality-building contents the longest because they have the greatest significance for our lives and form the metaphorical tether that stretches through our entire lives. The importance that the memory contents - clothes on the clothesline - have for our lives is the second building block for longer or better remembering, next to strong feelings.
We edit our memories
Biographical memory data is by no means unchangeable, but changes all by itself in the course of time, as we change in the meantime and take in new experiences, attach a different meaning to the memories and tell or remember them in a new context with reference to certain aspects. Phrases like "everything was better in the past" show how memories are compared with current events. Anecdotes from the Bundeswehr days become funnier in each new round of telling, even though the experience itself had a different emotional impact. In the process, our current self-image is compared with our memories.
The philosopher Michael Jungert describes identity and memory as dynamic variables. In people with dementia, identity therefore does not disappear as memory fades. For even in advanced dementia, certain behaviours and movement patterns remain. The surrounding persons recognise this and remark: this is 'quite him' or 'typically her', so the individual person is preserved even if he or she does not remember him or herself.
Better memory: Simple memory sport for everyone!
The third building block for remembering things better is the uniqueness of what we want to remember. "What we do for the first time is easier to remember," says neuroscientist Gerald Hüther. Frequently experienced things are sorted out and stored as a standardised pattern. We know this: we take a certain route to work, and when we want to go somewhere else on the same route, we take a wrong turn because we always do it that way. It's like that with everything that becomes routine. Even last week's lunch is remembered by very few; unless it was prepared in a very special way, in a special place or perhaps with a special person.
"Contrary to common belief, our memory is not primarily there to remember, but to plan the future," says Hüther. Social contacts, especially the exchange and learning that takes place, are important for our mental fitness in old age.
So the third building block of easy remembering - the uniqueness of the experience - is a tip for mental fitness in old age: trying something new and doing familiar things differently; for example, running up the stairs backwards or taking a different route for a change.... and also creating images, as with the metaphor of the clothesline in this article. If we associate things we want to remember with familiar patterns, we find it easier. If we want to remember ten things, we simply assign each one with a mnemonic to the ten closest houses in the street where we live.
