LTM is stored and retrieved by association. For example, if a group of participants are given a list of words to remember, and then asked to recall the fourth word on the list, participants go through the list in the order they heard it in order to retrieve the information. STM is stored and retrieved sequentially. When we are asked to retrieve something from memory, the differences between STM and LTM become very clear. If we can’t remember something, it may be because we are unable to retrieve it. This refers to getting information out storage. Information can only be stored for a brief duration in STM (0-30 seconds), but LTM can last a lifetime. In contrast, the capacity of LTM is thought to be unlimited. Indeed, if we can “chunk” information together we can store a lot more information in our short-term memory. However, Miller didn’t specify the amount of information that can be held in each slot. He though that short-term memory capacity was 7 (plus or minus 2) items because it only had a certain number of “slots” in which items could be stored. Miller (1956) put this idea forward and he called it the magic number 7. Most adults can store between 5 and 9 items in their short-term memory. There has been a significant amount of research regarding the differences between Short Term Memory (STM ) and Long Term Memory (LTM). The way we store information affects the way we retrieve it. This concerns the nature of memory stores, i.e., where the information is stored, how long the memory lasts for (duration), how much can be stored at any time (capacity) and what kind of information is held. However, information in LTM can also be coded both visually and acoustically. The principle encoding system in long-term memory (LTM) appears to be semantic coding (by meaning). Rehearsal is a verbal process regardless of whether the list of items is presented acoustically (someone reads them out), or visually (on a sheet of paper). When a person is presented with a list of numbers and letters, they will try to hold them in STM by rehearsing them (verbally). There are three main ways in which information can be encoded (changed):įor example, how do you remember a telephone number you have looked up in the phone book? If you can see it then you are using visual coding, but if you are repeating it to yourself you are using acoustic coding (by sound).Įvidence suggests that this is the principle coding system in short-term memory (STM) is acoustic coding. For example, a word which is seen (in a book) may be stored if it is changed (encoded) into a sound or a meaning (i.e. Think of this as similar to changing your money into a different currency when you travel from one country to another. When information comes into our memory system (from sensory input), it needs to be changed into a form that the system can cope with, so that it can be stored. images, sounds or meaning.įor psychologists the term memory covers three important aspects of information processing: This information takes many different forms, e.g. Memory is involved in processing vast amounts of information. Without memory, we could not learn anything. We would not be able to remember what we did yesterday, what we have done today or what we plan to do tomorrow. Without a memory of the past, we cannot operate in the present or think about the future. Memory is the term given to the structures and processes involved in the storage and subsequent retrieval of information. “Memory is the means by which we draw on our past experiences in order to use this information in the present’ (Sternberg, 1999). “Memory is the process of maintaining information over time.” (Matlin, 2005)