The Multistore Model Flashcards
What is short term memory?
Your memory for immediate events.
It temporarily stores information revived from the sensory register.
What is long term memory?
Permanent information for events that have happened in the more distant past and are enduring
What is the multi-store model of memory?
Proposed by
ATKINSON AND SCHIFFRIN
The MSM is a model which represents the flow of information through the memory system.
It proposed that memory is made up of three separate memory stored linked together by processes that enable information to transfer from one store to the next.
Each store has a different purpose and each differs in terms of coding, capacity and duration.
What three stores is the multi-store model of memory made up of?
Coding
Capacity
Duration
Sensory register
Short term memory
Long term memory
The form info is stored
How much info can be stored
How long info can be stored for
What is the sensory register?
1
2
3
What is the coding of the sensory register?
What is the capacity of the sensory register?
What is the duration of the sensory register?
The sensory register temporarily stores information from our senses.
separate stores for each of the 5 senses.
The two main stores are iconic (visual information is first encoded visually)
and echoic (sound based info is first encoded acoustically).
Information is coded depending on the sense that is picked up
e.g. Visual, auditory or tactile
The sensory register has a huge capacity
The sensory register has a very limited duration of 0.5 - 2 seconds
What study provides evidence for the capacity of the sensory register?
Sperling
3x4 grid of letters - have to recall one row
Sperling conducted a lab experiment in which a 3x4 grid of letters was projected for 50 milliseconds, and participants were asked to recall letters of one row.
Recall of the indicated row was high which suggests that all informs was there
indicating the capacity of the SR is quite large
What study provides evidence for the coding and duration of the sensory register?
CROWDER
info showed visually (iconic state)
few ms
Info showed acoustically (echoic state)
2-3s
Support they have different durations and different codings
How does information pass from the sensory register to short term memory?
You have to pay attention to the information in the sensory register for it to pass on to STM
What is the key process in STM and why?
Maintenance rehearsal (verbal repetition of information) as it allows us to keep info in STM long enough to use it.
E.g telephone number
Also, if we rehearse information for long enough it will eventually pass into our LTM.
What is Short term memory:
How is information coded in short term memory?
What is the capacity of short term memory?
What is the duration of short term memory?
for immediate events - temporarily stored information received from sensory register
Acoustically
5-9 items
18 - 30 seconds
What study provides evidence for how information is coded in STM and STM- coding?
Evaluate
Baddely
Lab experiment where participants were given acoustically similar/dissimilar
or semantically similar/dissimilar words to learn.
Participants were asked to recall words in the order they were first given either immediately (to test STM) or after a 30
Minute delay (to test LTM).
Immediate recall was worse with acoustically similar words, and delayed recall was worse with semantically similar words. This suggests that information is largely encoded acoustically in STM and semantically in LTM.
✅
• Lab study - high degree of control over extraneous variables
• Made sure they were all familiar words, to prevent word familiarity becoming a confounding variable - could therefore establish cause and effect
❌
The words used had no personal meaning to the participants. When processing more meaningful information, people may use semantic coding even for STM tasks. This means the results of this study have limited application so we may not be able to generalise the findings.
Sensory register studies
1. Coding
2. Capacity
3. Duration
- Coding - Crowder
(Visual few ms) (sound based 2-3s) - Capacity
3x4 grids - Duration - Crowder
(Visual few ms) (sound based 2-3s)
What study provides evidence for the capacity of STM?
Evaluate
Miller used experimental findings from several different experiments to support his idea that on average, STM can hold 7 plus or minus 2 chunks or bits of information.
He stated this can be increased by chunking.
✅ Has many practical applications such in postcode system. This shows how research into the capacity of STM has helped thing to be easier to remember in a real life situation
❌
Limitation is that he may have overestimated the capacity of STM. More recently, researchers reviewed other research and concluded that the capacity of STM was only about 4 items. This suggests that the lower end of Miller’s estimate (5 items) is more appropriate than 7.
What study provides evidence for the duration of short term memory?
Evaluate
Peterson and Peterson trigram
Lab experiment where participants were given trigrams which they had to recall after varying amounts of time from 0-18 seconds.
On presentation of each trigram, they were required to verbally count backwards in threes to prevent participants rehearsing the trigrams.
Average recall after 18 seconds fell to 10%.
Suggesting that the duration of STM is approximately 18-30 seconds if rehearsal is prevented.
❌
Limitation = artificial stimulus
Trying to memorise trigrams does not reflect real-life memory activities where what we try to remember is meaningful. So it could be argued that this study lacks external validity.
✅
However, we do sometimes try to remember fairly meaningless things like phone numbers - so the study is not totally irrelevant.
Long term memory:
How is long term memory coded?
What is the capacity of long term memory?
The potential capacity of long term memory is unlimited
What is the duration of long term memory?
Relatively permanent:
Semantically (by meaning)
The duration of long term memory is potentially unlimited
Processes
SR - STM
STM - STM
STM - LTM
LTM - STM
Attention
Maintenance rehearsal
Prolonged rehearsal
Retrieval
What study provides evidence for the coding of long term memory?
Baddeley
Acoustically similar/dissimilar + semantically similar/dissimilar words.
Worse recall of semantically similar words after 20 min delay suggests LTM is coded semantically.
What study provides evidence for the duration of long term memory?
Evaluate
Bahrick et al Yearbook - memories of other students.
Field experiment to explore the length of time memories can be retained. They tested the memory of American graduates participants of their former classmates using their yearbooks.
Participants who were tested working 15 years of graduation were about 90% accurate in photo recognition,
suggesting that LTM can last a very long time.
✅
High external validity - field experiment where real-life meaningful memories were studied so the behaviour shown was more valid and authentic
❌
Real-life research = lack of control over confounding variables, such as the fact that the participants may have looked at their yearbook photos and rehearsed their memories over the years.
Studies of LTM
Coding
Capacity
Duration
Coding: Baddely
Capacity:
Duration: Bahrick
Studies of STM
Coding
Capacity
Duration
Coding: Baddely
Capacity: Milgram
Duration: Peterson and perversion trigram
Evaluation of MSM
S
L
L
L
S: evidence for separate STM and LTM
MSM only explains one type of rehearsal
MSM relies on artificial tasks
MSM oversimplifies LTM
Evaluation of MSM
S: Evidence for separate STM and LTM
The MSM is supported by research showing that STM and LTM are separate stores with different functions.
Murdock’ serial positions curve provides further support for the existence of two separate stores.
Lab experiment - participants presented with lists of words to be recalled in any order.
More words were recalled from the beginning of the list (the primacy effect) and the end of the list (the recency effect).
There was poor recall of words in the middle of the list.
The primacy and recency effects are taken as strong evidence for the existence of two separate memory stores with different functions.
Evaluation of MSM
L: Only explains one type of rehearsal
A limitation of the MSM is that it only explains one type of rehearsal; maintenance rehearsal. It’s claim that maintenance rehearsal (verbal repetition of information) is essential for transferring info into LTM has been disputed.
Researchers claim there are two types of rehearsal - maintenance and elaborative. They claim that maintenance rehearsal simply keeps info in the STM and that elaborative rehearsal is needed for long term storage.
Elaborative rehearsal is where info is linked to existing knowledge or you consider its meaning.
This is a very serious limitation of the MSM because it is a research finding that cannot be explained by the model.
Evaluation of MSM
Relies on artificial materials
A limitation is that the research studies supporting the MSM use artificial materials. The MSM is supported by highly controlled artificial lab experiments where patients are asked to recall letters, digits etc. which may undermine the validity of the model. In real life we form memories related to useful things such as names, facts, places etc.
This suggests the MSM lacks external validity. Research findings may reflect how memory works with meaningless material in lab testing, but does not reflect how memory mainly works in everyday life.
Evaluation of MSM
Oversimplifies LTM
A limitation of the MSM is that it oversimplifies LTM. There is a lot of research that suggests LTM is not a unitary store.
We have one LTM for memories about the world (semantic), and a different one for memories of how to ride a bike (episodic).
The MSM is limited because it does not reflect these different types of LTM.
