Long Term Memory (LTM) is influenced by many factors. It is not just a storehouse of information but a vigorous system in which knowledge is being continually updated, revised and modified in the light of new experiences or fresh information. LTM is also an interrelated system in which items of information are bonded together in a huge and complex web. This essay will examine the characteristics of LTM by looking briefly at its function, coding, and capacity. It will then focus on the organisation of LTM, examining this in more depth.Finally, these concepts will be applied to developing an understanding of how memories are stored, retrieved and ultimately forgotten before looking briefly at some strategies that can be used to improve memory.
LTM cannot be characterised in terms of capacity or duration as it has no known limits on either. Instead, LTM is a great diversity of information storing all kinds of knowledge, beliefs, commodities and events. Inputs on the memory are encoded by using visual, acoustic or semantic representations.Bousfield's (1953) research shows that subjects could recall items better if they were placed into semantic categories of words of similar meaning. Bower, G.
H. , Clark, M. C. , Wizenz D.
and Leggold A. M. (1969) advanced this research by arranging the categories into hierarchies. In their experiments, participants who learned words in clusters of hierarchies remembered 64% of 112 words learned, with 100% recall; those learning random words remembered only 18% of words, with 47% recall.
Tulving (1972) then proposed that LTM has 2 different systems that were neither complementary nor completely separate.These were episodic memory, consisting of personal experiences, and semantic memory, representing more general knowledge. Both of these memories are organised in categories to make them more accessible, episodic in dimensions of time and space and semantic in knowledge. So, the brain needs order and works in hierarchies; yet, in semantic memory not all items of the same meaning have the same hierarchical status. Information that is frequently used such as that a robin is a bird will be more readily associated than uncommon information such as that a penguin is a bird even though both pieces of information relate to birds.
Due to this, Collins and Loftus (1975) proposed that LTM followed a network model where related concepts were grouped into interconnected clusters instead of grouping knowledge by simple hierarchical structure, as first proposed by Collins and Quillen (1969). Therefore, concepts that were closely related and shared many links would lie close together within the network; the paths connecting them would be short and the more frequently the links were used the stronger they would become.Conversely, these clusters would often only bond to other clusters with weak links, if at all, making the network limited. This model was able to explain the 'typicality effect' as the activation model showed that speed of access was dependant on the strength of the path; if the path wasn't used frequently it would take longer to retrieve the information. Understanding the characteristics of LTM allows development of strategies to improve it. Although there are no discernible limits to its capacity or duration, memory is not infallible.
In order to try and improve memory we must first understand why some information is forgotten. The main reason for forgetting information in LTM is interference, of which there are two main types. Proactive interference occurs when information you learn first interferes with subsequent information. Retroactive interference occurs when more recent information interferes with previously learnt material. McGeoch and Macdonald (1931) discovered that recall was most effected when items learned were similar to each other.
This may be due to the fact that semantic memory stores all similar words in the same cluster group as shown by the work of Bower et al, as the memory needs a way of organising information in order to retrieve it. During the retrieval process, the mind homes in on the storage location within the memory where words are grouped and associated on the basis of similarity in meaning or sound. Retrieval can, therefore, be imperfect; although the brain may succeed in locating the correct clusters of information the technique of storing similar items in clusters may cause it to fail to retrieve the correct item.Yet, if the required knowledge is linked along already learnt responses then automatic linkage can be directed; this causes retrieval to occur automatically as a result of activation spreading along the linkage pathways as seen in Collins and Loftus work. So, in order to improve memory and to make it accessible some order must be imposed on the mass of information that an individual wishes to learn, linking typical words together to form stronger bonds. As LTM is flexible, a number of highly individual strategies can be used to organise and retrieve memories by adapting various mnemonics strategies.
People can do this by learning ways to combine the information together to enhance performance on memory tasks. They can do this by making material more meaningful, fitting new information to an already learned framework or elaborating information by images or associations that would form stronger bonds. One of the strategies that can be used is the method of Loci, by using an already learnt topic (i. e. a layout of a room) a person can relate certain items to objects in that room, thereby piggybacking a new response onto an already learned response.People can also use a story linkage where words are linked together by incorporating them into a story.
By doing this, the memory is creating stronger bonds between the words making their recall easier to achieve. Although these are only a couple of methods, it can be seen that by understanding LTM an individual can learn to improve it. So, the main characteristic of LTM is that it needs order, achieved by the semantic grouping of clusters of words and the use of hierarchies.Further, there are two types of memory, episodic and semantic and these work in a network where information more frequently used will become quicker to retrieve. An individual can use this understanding of the characteristics of LTM in order to develop strategies to improve it.
As the memory forgets information due to interference, especially with information of similar nature, order must be imposed on our memories to form stronger bonds so that information can be retrieved. Organising and retrieving memories by adapting various mnemonics strategies, such as Loci and story linkage, can achieve this.
