Memory Processes
Photo Courtesy: http://www.waynereid.com.au/human_memory.html
Encoding
Processing information into memory is called encoding. Some people automatically encode some types of information without even being aware of doing so. However, other types of information can only be encoded if people pay attention to it. There are several different ways to encode memory: visual encoding, acoustic encoding, semantic encoding and tactile encoding. Visual encoding is the processing of images and acoustic encoding is the processing of sounds, particularly the sound of words. Acoustic encoding is used primarily for short-term memory. Semantic encoding s the processing of meaning, mainly the meaning of words, and tactile encoding is processing how something feels, generally through touch. Information encoded into long-term memory is usually processed semantically.
Storage
Information needs to be stored or maintained after it enters the brain. Most psychologists use the three-stage model proposed by Richard Atkinson and Richard Shiffrin to describe the process of storage. According to the model, information is stored sequentially in three memory systems: sensory memory, short-term memory and long-term memory.
Sensory Memory
Although the capacity of sensory memory is large, most of the information is it is unprocessed. Sensory memory stores incoming information in detail but only for an instant.
Short-term Memory
Short-term memory can retain information for about twenty seconds. Rehearsing can help keep information in short-term memory longer. Short-term memory has a limited capacity; it can store about seven pieces of information (plus or minus two).
Long-term Memory
Long-term memory has almost an infinite capacity. The information in long-term memory usually stays there for a long time, often throughout a person’s life.
Organization of Memory
One way the brain organizes information into long-term memory is by category. Categories can be based on how things sound or look. Other ways to organize information are by information’s familiarity, relevance or connection to other information.
Photo Courtesy: http://www.aboutmind.com/pictures/memory.gif
Retrieval
The process of getting information out of memory is retrieval. There are two types of information retrieval: recall and recognition. In recall, the information is replicated from memory. In recognition the arrangement of the information lets us know that the information has been seen before. Recognition is less complex, because the information is given as a reminder. However, recalling can be assisted by retrieval cues which allow people to quickly access the information in memory. Stimuli that can help the process of retrieval are known as retrieval cues. Some retrieval cues are associations, context and mood.
Associations
The brain stores information as networks of associated concepts. Because of this, recalling a particular word is easier if another, related word is remembered first. For example, if after writing an essay Sarah was asked to spell right, she may spell write because the the act of writing beforehand may have led her to recall that form of the word. This process is known as priming.
Context
People can often remember an even better by placing themselves in the same context they were in when the particular even happened.
Mood
People may have an easier time recalling an event if they are in the same mood as they were in during the event.
Photo Courtesy: http://www.science.ca/images/scientists/s1-tulving.gif
Studies have shown that when people are trying to encode words into memory, the frontal and temporal cortex in the left hemisphere “lights up” with activity, but the right hemisphere encoding left does not. On the other hand, when people recall previously learned material, the right frontal cortex "lights up". The left hemisphere is active in retrieval, too, but not as much.
