Not remembering if we have locked the car, going to get the keys or the mobile phone and having it in our hands, not remembering where we have parked, and, of course, forgetting what we were going to say. These are everyday and somehow funny situations in which memory reveals itself against us .
All these events make the person who experiences them wonder if they have a bad memory or if they are unintelligent. Even the most hypochondriac will consider going to the doctor in search of a diagnosis of Alzheimer’s.
But there are reasons to remain calm; these experiences do not show intellectual deficits or signs of neurodegenerative diseases, but rather it is a common psychological phenomenon that is due to the limits of our short-term memory .
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Did I lock the car? Short term memory and its failures
Let us remember that short-term memory is that which allows us to interact with the present environment , since thanks to it a small amount of information is actively kept in the mind, so that it is immediately available, at least, for a short period of time.
When we have a conversation, perform mathematical calculations or talk to ourselves, we are making direct use of this memory. However, this memory is not perfect, on the contrary .
The magic number seven
Psychologist George A. Miller was the first to investigate these phenomena, and published an essay called “The Magic Number Seven, Plus or minus two” in which he reflects the limits of our ability to process information that we find within the ranges of short-term memory (SCM). According to Miller, short-term memory has a limited storage capacity, ranging from 5 to 9, or 7 plus or minus two. This is a biological limitation posed by our nervous system .
This means that when we retain 7 units of information in the present moment, we are not able to perceive what is beyond these “data packages” since all external stimuli have no space to enter our memory in that particular moment.
The role of care
Attention is the psychological process that goes hand in hand with short-term memory, which is also highly limited. Miller clarified that it is possible to increase the number of elements a person processes if what they perceive is a matter of importance and value for the individual. However, if it is not of interest to him, and he is already occupying the space, it will not be stored in his memory.
This explains that although we are occupying all the capacity of our short-term memory, if we perceive (even if unconsciously) a spider in front of us, all our attentional resources will be directed to it and not to our thinking . Here lies the functionality of this memory being limited, at times when man was fighting for his survival with other species, those threatening stimuli could not do without this scarce space in the memory.
Conclusions and reflections
You might now understand why you often don’t listen to someone who’s been talking to you for three minutes. Surely, whatever you had in your head while this person was talking to you, occupied those 7 plus minus two packets of information that you are able to retain and, evidently, it was much more important to you your own affairs than what that person was telling you.
We can also raise the situation we discussed initially about whether or not the car is locked. When we get out of the car, we usually do so in a hurry and thinking about everything we need to do after parking. That is why at the moment of closing the car our short-term memory is completely full of information and even if we have closed the car unconsciously and automatically (since it is a very routine action), since our consciousness is busy, for us it is as if we had not lived it.
Something similar happens in all those situations in which the number 7 puts on the table, once again, that the human being is not perfect, but prey of his limited psychological processes .