Is the memory necessary for the consciousness?

Memory: Why We Forget

Who likes to admit to having misplaced their glasses or having an appointment sweaty? Even among memory researchers, forgetting is considered the opposite pole to remembering, if they pay attention to it at all. It is much more than just a gap in the memory - it is an integral part of it. What we remember, experience or plan for the future depends not only on our existing memories, but also on everything we no longer know. The situation resembles a marble sculpture that has only just been created through the removed rock.

Since our lives are constantly changing, it is crucial for our brain to forget. In order to adapt to changing environmental conditions, we have to learn new things as well as unlearn (i.e. forget) and relearn what we have already learned. This can be illustrated well by means of perception: We have to briefly remember what we see, feel, hear, taste or smell, but only until the next sensory impression arrives.

More than a gap in the memory
  1. Forgetting is not always a memory mistake, but often an important and active process. Only those who forget can separate the unimportant from the important, think abstractly and solve problems. In addition, it helps to remember.

  2. The cellular mechanism of forgetting is similar to that of learning and takes place at the same synapses in the hippocampus and in other brain areas. However, it is unclear whether we will actually delete content or whether it will only become more difficult to access it.

  3. Our memories change with every view. In people with post-traumatic stress disorder, however, the traumatic experience is stored as if it was write-protected. Researchers are looking for ways to change that.

This article is featured in Spectrum Compact, Neuroplasticity - Malleable Brain

Because, for example, the processing of the visual impression in the retina takes longer than that of the sound in the inner ear, we store each input from a sensory system for about a quarter of a second, otherwise we would not be able to assign a voice to the corresponding lip movement. But as soon as the next sensory impression follows, the old one has to be deleted so that the two do not overlap. Erasing and forgetting are therefore not errors or dropouts in perception, rather they are an integral part of the necessary processes. On the other hand, we only afford long-term storage and remembering for a tiny part of our experiences.

When we save something new, it often makes sense to overwrite previous events. So it is not relevant to us where we parked the car a week ago or where it is parked most often. Instead, we need to remember where we left it the last time. We constantly practice this type of focused forgetting, for example with old passwords.

Even the conscious memory of the first years of life, in which we learn an incredible amount, we forget in the course of life. We also go into a phase of amnesia lasting several hours every night. The essential prerequisites for memory formation are missing during sleep: the instances of the brain that convey self-awareness are in a state of rest. But this awareness is necessary in order to be able to store something in the autobiographical memory. Likewise, those neurotransmitters that are needed to store what has been learned by strengthening communication between nerve cells, such as acetylcholine, dopamine and norepinephrine, are not very active. What appears to be a mistake, however, makes sense if you take a closer look: In order to consolidate what you have experienced during the day, nothing disturbing new should be added. Just as you close your eyes in order to concentrate, the brain blocks out the present during sleep in order to be able to store particularly well. Therefore sleep is essential for memory formation.

The German word "vergessen" is based on the stem "gessen" and originally expressed a movement in the direction of the speaker; so he "gets" something. The prefix "ver" turns it into the opposite. So forgetting from the root of the word is an active process - contrary to our everyday understanding. In fact, forgetting does not happen passively in the brain either, for example when synaptic connections that have not been used for a long time simply become weaker. Instead, it resembles a well-programmed spam filter that is inherent in our memory. If this does not work, you are overwhelmed by the wealth of irrelevant information. Even abstract thinking only works if we leave out, ignore and forget a lot of information. Individual memory savants fail to do this. These people are celebrities because they remember roughly every word in a book they read. But they cannot use their knowledge to creatively solve problems or discover new things.