Assignments 12- outline and evaluate in to the duration, capacity and encoding of information in short term memory
Capacity refers to the amount of information that can be held at any one time in memory. The Capacity of STM is limited and to demonstrate the capacity of STM, the serial digit span technique is used. The study was proposed by Jacobs where experiment needed the participants to read lists of either words/numbers that they had to recall immediately after presentation. The finding found that there was a difference between capacity for numbers and for letters. Also an average participant can only recall 9 for numbers but only 7 for letters. The conclusion was that short term memory has the capacity of between 5 and 9 items of informationIt is shown that if our age increases we appear to develop better strategies in recalling but not to the stage of the elderly.
Later studies (Miller 1956) have also supported Jacobs' findings and conclusions. Miller published his findings in an article entitled "The magic number seven, plus or minus two." However it could be argued that most memory research like this lacks ecological validity. As you are using your memory for an artificial task, it may not tell how memory works in everyday life. It is one of the most repeated studies into human memory and other studies tend to replicate the original findings of it. Some studies have also discovered signs of interference. When being tested on later trigrams, participants have erroneously recalled earlier ones. This suggests that recall can be much longer than 18 seconds.
As with span measures, this technique is very artificial so again is lacking in ecological validity. Apart from in a psychology lesson, has anyone ever asked you to recall random groups of consonants?
Some studies have also discovered signs of interference. When being tested on later trigrams, participants have erroneously recalled earlier ones. This suggests that recall can be much longer than 18 seconds.
As you probably discovered yourselves, it is also very easy to cheat when being tested.
Duration refers to the amount of time that a memory can be stored. Duration in STM is measured by the Peterson & Peterson technique. This is one of the most repeated studies into human memory and other studies tend to replicate the original findings.The technique used in this study is very artificial therefore it lacks ecological validity.This is because in a normal basis of life you're not told to recall random groups of consonants.
Encoding refers to the format or code in which a memory is stored as a memory trace. Encoding can be by acoustic or by semantic. It was concluded that in STM information is encoded by its sound (acoustically) so when we recall information from STM we may get confused if there are similar sounding words.