multi- store model

what is the multi store model?

A representation of memory. It helps us to understand how our memory works and what it might ‘look like’

diagram of MSM?

who proposed the MSM?

Atkinson & Shiffrin 1968

what’s the capacity of SR?

very large

What’s the duration of SR?

250-500milliseconds

Who discovered that the capacity of SR was very large/ duration was 250-500 milliseconds?

Sperling 1960

How did sperling discover the capacity of the SR was very large/ duration was 250-500 milliseconds? (Procedure)

Lab experiment. PPs shown grid with 3 rows and 4 letters on each row for 0.05 seconds. They had to immediately recall whole grid or just 1 row.

What were the findings of Sperlings Lab experiment on SR?

Found that when asked to recall while grid, they managed 4-5 letters on average. When asked for specific row they got an average of 3, (didn’t matter which row)

What was the conclusion from Sperlings findings?

Whole grid recalled 4-5 shows SR has fairly large capacity, but couldn’t recall while grid because duration is short without rehearsal so it had faded before PPs could finish the recall.

What’s the coding for SR?

Modality specific

What is the capacity of STM?

7±2 chunks

Who discovered that the capacity of STM was 7+-2 chunks?

Miller/Jacobs

What was the procedure of Miller/Jacobs experiment into capacity of STM?

Digit span test, 443 female students who were required to repeat back a string of numbers (digits) or letters.

what were the findings of Miller/Jacobs experiment?

on average PPs could recall 7.3 letters and 9.3 numbers

what was the conclusion of Miller/Jacob’s findings?

Capacity of STM is 7+-2 chunks

What is a strength of the studies into STM?

Studies are easily repeatable as the procedure/instructions are standardised.

→ increases validity

what’s two criticisms of studies into STM?

• samples aren’t representative (443 female students), can’t generalise to old men

• Artificial setting/ task- lacks mundane reslism (poor ecological validity)

What is the duration of STM?

18- 30seconds

Who discovered the duration of STM was 18 to 30 seconds?

Peterson&Peterson

What was the procedure of Peterson and Peterson’s study of duration in STM?

Lab experiment. PPs (24 psychology students) have to recall meaningless three letter diagrams at different intervals (3,6,9,12,15 seconds). To prevent rehearsal students had to count backwards in threes/fours

What were the findings of Peterson and Peterson’s study?

The larger the interval, less accurate recall. At three seconds, 80% of the trigrams recalled correctly, at 18seconds, 10% correctly recalled.

What were the conclusion of Peterson and Peterson’s study?

STM has limited duration of 18 seconds, if unable to rehearse information it won’t be passed into LTM, provide further support for MSM – idea of discreet memory stores

What is the coding of STM?

Acoustically coded

Who discovered the STM was coded acoustically?

Baddely 1966

What was the procedure of Baddelys study into coding in STM/ LTM?

72 PPs randomly allocated to 1 of 4 conditions. Each group shown a list of 10 words either acoustically similar/ dissimilar or semantically similar/ dissimilar.

• Group 1- words sound the same (acoustically similar)

• Group 2- words sound different (acoustically dissimilar)

• Group 3- words with similar meaning (semantically similar)

• Group 4- words with different meaning (semantically dissimilar)

  Recall tested either immediately (STM) or following a delay of 20 minutes (LTM)

What were the findings of Baddelys study?

immediately recall(STM) did worse with acoustically similar words

Time interval (LTM) did worse with semantically similar words

What was the conclusion of Baddelys study into STM/ LTM?

STM relies on acoustic coding – different sounding words stick better in STM

LTM relies on semantic coding – semantically different words to stick better in LTM

what’s the capacity of LTM?

potentially unlimited

what’s the duration of LTM?

a lifetime

Who discovered that the duration of LTM was a lifetime?

Bahrick- Yearbook study

what was the procedure of Bahricks yearbook study?

examined 392 American uni graduates on their memory of former classmates by asking PPS to match the names of former classmates to their picture in a yearbook photo.

what was the findings of Bahricks yearbook study?

47 years after graduation – 60% of accuracy for matching names and faces

what conclusion can be made about duration of LTM from Bahricks yearbook study?

Memory stored in LTM can last a lifetime or at least 47 years

What are two strengths of Bahricks yearbook study? (Research into duration of LTM)

• large sample size- more representative/valid

• Tasks more realistic of every day life/memory- doesn’t lack mundane realism

What are two weaknesses of Bahricks yearbook study? (Research into duration of LTM)

• Sample not representative to an extent- all uni graduates (392), may have better memory than the average person

What is the coding of LTM?

Semantically coded.

Who discovered the coding in LTM with semantically coded?

Baddely

What’s one strength of the MSM? (Research- CW)

Supported by research- Clive wearing (MSM/ memory is sequential)

→ CW suffered from brain damage which resulted in severe amnesia and was unable to transfer information from his STM to LTM

→ this matters because it demonstrate that the MSM is sequential and that of the ability to transfer information from STM to LTM is broken we can’t form new memories, thus supporting linear nature of the model.

What’s another strength of the MSM? (Research- diff elements of storage systems)

→ Miller found capacity STM is 7+-2 chunks based on PP’s average recall of strings of digits

→ likewise, Barwick found that PPS were 60% accurate at recalling classmates from the yearbook 47 years later demonstrating potential lifetime of LTM

→ this matters because it supports the idea that STM has limited capacity and LTM has unlimited capacity and that MSM is correct to assume that memory is divided into different storage systems and these systems have different coding, capacity and duration

what’s one limitation of MSM?

Some research contradicts unitary nature of STM- Patient KF

→ patient KF injured in motorcycle accident. Following his accident, patient KF was able to recall stored information from LTM however he had issues with his STM. He was able to remember visual images including faces but was unable to remember sounds (acoustic information).

→ this matters because it suggests STM is not a unitary store but is split into at least two parts. Shows us the overall MSM is limited (oversimplified) in its explanation of the true nature of STM.