Psychology defines memory as an organism’s ability to encode, store, retain, and retrieve information that it has acquired through an interaction with its environment. This includes both the internal and the external environment. Human memory is categorized into three different types: sensory memory, short-term memory, and long-term memory.
Sensory memory is the memory utilized in the time interval of 200-500 milliseconds after something has been sensed by the individual. Some of the information that is processed in sensory memory may be transferred to short-term memory where it can be stored for a longer duration of time, from a few seconds up to a minute. However, the capacity of short-term memory is limited. Long-term memory, on the other hand, has a greater capacity for storage than sensory or short-term memory.
The length of time for which information can be stored in long-term memory is also prolonged and limited only by the individual himself or herself. Different models of memory show different ways by which information reaches these three types of memory. However, there is a generally agreed upon process by which memory, in general, is formed and created.
The general process by which memory is created in an individual’s mind involves three stages: encoding, storage, and retrieval. Initially, an individual must first come into contact with something via the different sensory receptors. The sensation acquired fro the environment is then encoded by the memory system. This simply involves the transformation of the information from one form to another that is more compatible with the memory system. Information about space, time, and frequency can be processed during this stage either automatically or through effortful processing.
After a specific type of information is encoded, it undergoes the next step of the process: storage. Storage involves the holding on to the encoded information. A more permanent record is created and kept in one of the three classifications of memory, depending on whichever is more applicable to the type of information that is being processed.
After memory is stored, it is now made available to the third step called retrieval. Retrieval is simply the act of taking the memory out of its storage in order to use it for a specific function as deemed necessary by the individual. Retrieval may involve the reversal of the encoding process. This means that the stored information may be transformed back into a sensory form.
The encoding of memory can be enhanced through a variety of techniques. One such technique involves the assignment of meaning to the perceived object. Likewise, encoding may be impeded if the object sensed is ambiguous or unclear in nature. Encoding is also more effective when more senses are used. The greater amount of sensory information a memory has linked to it, the more meaningful its encoding.
The storage of memory also encounters impediments. One of the greatest impediments is decay,which involves the loss or fading of memories through time. Interference is another impediment to the storage of memory, both in short-term and long-term. This simply pertains to the fact that the presence of some information prevents other information to be stored.
In proactive interference, storage of previously acquired information disrupts the storage of newly acquired information. Retroactive interference, on the other hand, involves the disruption of storage of old memories due to the storage of new memories. Time must be given for the consolidation of memory into long-term memory before allowing other information to be stored.
Interference and decay effects can also be lessened through constant practice of memory enhancing strategies such as repetition of the information. This is also called maintenance rehearsal. Elaborative rehearsal can also enhance storage in that it links the given memory to other stored memories.
Retrieval is also made easier with a greater amount of links with the memory to be retrieved to other memories. This allows for more memory cues to be used in order to reach that piece of information. Thus retrieval can be enhanced with the use of priming, mnemonic strategies, and retrieval practice. Retrieval is easier when in the form of recognition as opposed to recall. This is because recognition makes use of the information itself as the retrieval cue. Decay in long-term memory is simply the decay of the link of the stored information and the retrieval cue. This decay is one of the causes for forgetting.
Information that never reaches the long-term memory is also forgotten easily as a result of the limited duration and capacity of both sensory and short-term memory. Faulty encoding and storage in long-term memory may also lead to forgetting. Also, faulty retrieval cues might lead to an inability to access data that is there but not actually linked to the “search words” used to reach it.
Other reasons for an inability to remember a piece of information may be distraction, wherein the individual’s attention is misdirected, and repression, wherein the motivation to retrieve the information is lacking or the system itself has closed off the memory due, for example, to trauma and the like. The act of forgetting may also by physiological and psychological in nature.
This is seen in cases of dementia and amnesia. There may be defects in the memory system or in the individual’s physiological make-up and these defects are the underlying cause for the inability to recall. Memory and its counterpart, forgetting, are complex topics that involve numerous concepts and models. It is only through a clear understanding of both that one can truly achieve a more efficient memory system that is less prone to the risk of forgetting.
Reference
Myers, David G. (2004). Psychology. New York: Worth Publishers