How Memory Works

Short Term Memory STM and Long Term Memory LTM

Our usual understanding of memory tells us that our Short Term Memory stores a small quantity of information for a short period of time. Our Short Term Memory consists of the information that we are consciously aware of such as something we are talking about, observing, listening to or thinking about. In contrast to this, the information in our Long Term Memory could be described as being 'at the back of our minds' i.e. it is stored away safely until we choose to use it.

When we absorb new information it is initially stored in our Short Term Memory for a short duration. Following this we either forget it completely, or it becomes stored in our Long Term Memory. The transference of information in to the Long Term Memory is dependent on techniques of repetition such as a child spelling a word out loud several times until they can remember it correctly.

Over time we accumulate a vast amount of information - our memories of events, faces, dates of special occasions, our education, conversations etc - and of course it isn't possible for it all to remain at the forefront of our mind - conscious - all the time. This information resides in our long term memory and when we become conscious of it again when we choose to retrieve it.

Psychological studies that look in to the process of remembering, reveal that Short Term Memory has a limited capacity in terms of the amount of information it can store at any one time, and the period of time it can be stored for. The general rule is that the Short Term Memory can only hold on to information for between 15 and 30 seconds before it is either discarded or passed on to the Long Term Memory. The Short Term Memory can store '7 +/-2' chunks of information, which means it stores approximately 7 pieces of information, give or take 2 in variance from person to person.

The implications of such a limit in capacity for the Short Term Memory means that once it has reached its limited of 7 items of information, then if we try to intake an additional piece of information, something will have to be discarded in order to make room for it. The Long Term Memory, on the other hand, is acknowledged to be potentially limitless in its capacity and duration. The trick is, to know how to make the information significant enough to transfer into the LTM.

Encoding

The term 'encoding' is used to refer to the way the information is absorbed. For instance, a piece of information may be processed visually (when we remember images), auditory (when we remember sounds and words), and semantically (when we remember a particular meaning or concept). The way in which we take in information greatly affects how likely we are to remember it. Visual and auditory encoding is always eclipsed by semantic encoding. Think of how easily (and vividly) you can recall the moments in your life that were in some way special or rare; a wedding day, the birth of a child, a traumatic event, the first time you met a person who is now a close friend. When we attach importance and emotion to something, it is remembered easily - it is instantly transferred in to our LTM.

Primacy Effect

Memory studies reveal that the information we first come in to contact with is more likely to be remembered, than the information that follows it. For instance, the first sentence of a particular book will tend to be most memorable. This might also explain why our first impressions of people are so long lasting.

Enhancing our memory skills

One technique to aid the retention of information stems from the knowledge that the capacity of Short Term Memory is 7 +/- 2. If the STM can only hold 7 pieces of information, then any information that exceeds those 7 pieces will be instantly discarded. Therefore a successful technique used to improve the intake of information - known as chunking - involves the break down of information in to 7 distinct chunks.

For instance, if you are trying to remember a piece of new information - whether it be a phone number, or revising for exams -A method to aid your intake of knowledge is to divide it in to 7 different segments or chunks. This is known as 'chunking'. If we apply this to the process of remembering a long number such as 87469384674538, the number is longer than 7 digits it would be very difficult to remember 14 separate numbers. Therefore, in order to increase the likelihood of remembering it we can separate it in to 7 distinct chunks: 87 46 93 84 67 45 38.

Our knowledge of encoding can also be of use in enhancing our memory. If we acknowledge that information that we take in semantically i.e. with an attached meaning, is more likely to be remembered than visual or auditory information, then we can attempt to alter the way we process information.

For instance, if you are revising for an exam and are trying to remember a particular theory then rather than reading about it, or saying it aloud, you could try relating the theory to yourself, think of an event in your own life that exemplifies the theory, and attach it to an evocative memory. If you are trying to remember names, perhaps of researchers or writers, then you could try to change their names to make them sound like something memorable or humorous to you. You may find your own techniques to attach relevance to information. But it is a useful tip to bear in mind that information is more easily remembered when we find it meaningful or attach some personal significance to it. If the information your are trying to remember isn't particularly personal or evocative then instead you can try and attach it to something else. For example, often when people need to remember their car registration number they make a funny word out of the characters, or they might remember some of the numbers by reminding themselves of a friend whose Birthday shares that number.

The trick in ensuring that memory stored in the Short Term Memory transfers successfully in to the Long Term Memory is to make the information stand out, to make it unusual in comparison to all the other information around you.