Memory can be defined as our ability to retain information and remember it when we later need it. This is one of the most studied fields in Cognitive Psychology and it has been approached in many different ways throughout the years.
There was a time where the memory capacity comprised the majority of the exercises in intelligence tests. Today, we know that it’s not accurate to directly relate memory with intelligence, but it is a fact that our memory is important to almost everything.
Therefore, many scientists tried to study and test the human memory. The initial tests were made with a list of words that the individual should try to memorize. It was just a list with unrelated words and soon enough, they understood that it had no scientific validity.
But the studies evolved and the theme was approached in many different ways, from different points of view. There were those who tried to determine the structure of our memory, as in, how it was organized, others, the process, the way it works and how the information is retained in our memory, the way it’s coded and how we recover it, and there were even the ones who focused on the oblivion and how information disappeared from our memory.
Atkinson–Shiffrin memory model
After William James had defined that there are two different systems of memory (Primary Memory, which is what is conscious in every moment, equivalent to what we call today Short-term Memory and Secondary Memory, which would be equivalent to what we call Long-term Memory, with James defining it as what is permanently in our mind) Atkinson and Shiffrin developed, in 1968, a model of how memory would work.
This model talked about different storages of information, each one with its own characteristics.
The first storage, called Sensory Memory, is the one that receives the sensory input from the environment. It has a very short focus time (1 sec) but it can receive unlimited information.
When something gets your attention, you stay focused on it and this information will pass through to the second storage: Short-term Memory. Here, the information stays for a longer time period, but not by much. Actually, scientists talk about some 20 to 30 seconds of permanency in this storage. The Short-term memory has an even more interesting characteristic: it cannot store too much information (nearly 7 pieces of information at a time).
Then, the repetition of information, its meaning and context will allow some of it to pass through to the third storage: Long-term memory. With unlimited space, the long-term memory will retain the information, supposedly for the rest of your life… So, why can’t you remember it whenever you need it? Well, according to Atkinson and Shiffrin the inability to recover the information doesn’t mean that it isn’t there…
I will talk about each one of these storages with more details soon and presenting you some studies about them in the following posts.