Description of MSM
Atkinson and Shiffrin's 1968
Suggests that memoery consists of a series of interconnected stores
They include... sensory information store (SM)...Short-term memory (STM)...Long-Term memeory (LTM)
The memory stores are different in these ways...
Encoding - Information to be remembered has to changed or encoded into a different form for each store.
Capacity - means how much space there is in each memory store.Each having a differnet capacity.
Duration - means how long the information lasts in the store. 'lifespan'.
The sensory memory briefly stores sensory images
SPERLING 1960... tested the sensory by showing people three rows of four mixed numbers and consonants for 50 MS then sounding a tone )high, medium or low) to signal which row they should recall (top, middle or low) .
He found from this that...
encoding is in the form of neutral activation of the visual sensory system
capacity ranges between five and nine item... magic number 7 plus or minus 2
duration is about half a second in people
Short term memory.. encoding
Information that is deemed relevant is then sent to the short term memory store
to achieve this it has to be recoded from its original form possibly into a word sound, eaning or images, formally known as acoustic, semantic and visual encoding
encoding for the STM is a very quick process
CONRAD 1964... studied acoustic confusion errors by briefly showing people a series of random sequences of 6 consonants in rapid succession on a screen and asking them to write the letters down in the correct order. Letter sequences were either acoustically similar.. for example T,V,P,B,C,D or a dissimilar for example F,J,R,Q,Z,V... people experienced both conditions.
Most common errors made by people were acoustic, its which they substituted similar sounding consonants for the original ones .. B instead of P.
concluding that STM encodes encodes acoustically.
Short term memory.. capacity
MILLER 1956! said that the STM can hold up to 7 things plus or minus 2. This is now known as Miller's magic number 7...
He showed this by reading lists of digits to participants who immediately had to repeat back each lists in the correct order. Lists started with three numbers and increased in size one number at a time until recall was accurate on 50 per cent of trials. Miller called the max number of digits that could be recalled in the correct order at that point the immediate memory span!
The STM was seen as having about 7plus or minus boxes, each of which could hold one item of information and No more. Miller claims that the rule of the magic number 7 applies to both letters and numbers.
Factors effecting short term memory...
FACTORS WHICH AFFECT!... AGE.. children's STM capacity increases rapidly as they grow, starting at about two items at the age of 2, levelling off at about 6 at 9 years old. The increasing to magic number 7 i n teens ages years. although there can be wide variations estimated at between 4 and 10 or more.
Reading aloud.. reading lists out loud before recalling them leads to superior recallcompare to reading them in your head, or having them read to you.
Rhythm.. grouping items together and recalling them with intonation and pauses helps toincrease STM capacity. We do this without knowing then recalling car number plates, telephone number. This is a form of chunking.
Chunking.. Miller claimed that STM capacity could be increased if items of information were organised into for example arranging digits into dates or letteres into words. In theory, the amount of information in each chunk could be quite large providing it meaningful to the individual. BUT STILL ONLY MAGIC NUMBER!