Model of memory = The structure and function of the brain (neurophysiology) are complicated to understand; therefore, cognitive
psychologists use theoretical models to simplify the processes underlying memory.
The multi-store model (MSM) of memory: Devised by Atkinson and Shiffrin (1968), was the first cognitive description of memory. It
views information as passing through a series of linear storage systems: The Sensory Register (SR), Short-term Memory (STM)
and Long-term Memory (LTM).
Each stage varies in terms of:
Coding = the format in which the information is kept. Rehearsal Loop
Capacity = the quantity of information that can be stored.
Duration = how long it can be stored for.
Transfer
Attention
Sensory Short-Term Long-Term
Register Memory Memory
MSM =
Retrieval
A summary of the features of each store:
Sensory Register Short-term Memory Long-term Memory
STM capacity
STM duration Coding Sense Specific can be increased
can be
(different stores for Mostly acoustic (by Mostly Semantic (by by chunking
increased by sound) meaning) items together
verbal rehersal. each sense) (Miller 1959).
Capacity Very large capacity Small - 7+/-2 items Potentially unlimited
Duration Breif 1/2 second Short (max 30 seconds) Potentially a lifetime
Research Support
Peterson and Peterson (1959)
Aim: Peterson & Peterson (1959) investigated the duration of short-term memory by conducting a laboratory experiment with a
sample of 24 psychology students.
Procedure: The students had to recall meaningless three-letter trigrams (for example, THG, XWV) at different intervals (3,6,9,12,15
or 18 seconds). To prevent rehearsal the students had to count backwards in threes or fours from a specific number ,until they were
asked to recall the letters.
Findings: Peterson & Peterson found that the longer the interval, the less accurate the recall. At 3seconds, around 80% of the
trigrams were correctly recalled, whereas at 18 seconds only 10% were correctly recalled.
Conclusion: Peterson & Peterson concluded that short –term memory has a limited duration of approximately 18 seconds.
Furthermore, the results show that if we are unable to rehearse information, it will not be passed to long-term memory, providing
further support for the multi-store model and the idea of discrete memory stores
GRAVE: High standardised procedure and it is scientific. Therefore it has high reliability and replicability. However, low ecological
validity as artificial stimuli was used.
, Bahrick (1975)
Aim: Investigated the duration of LTM.
Procedure: Examined 392 American university graduates on their memory for former classmates by asking participants to match
the names of former classmates to pictures in a yearbook photo.
Findings: 60% accuracy for matching names and faces 47 years after graduation.
Conclusion: Memories stored in LTM can last a life time or at least 47 years.
GRAVE: High ecological validity as real-life memories were used however it lacks population validity as we are unable to
generalise to other populations. High temporal validity as the results wouldn’t be the same today due to social media.
Miller (1956) and Jacobs (1887)
While Miller (1956) is commonly cited for his research examining STM, Jacobs (1887) actually conducted similar research 69 years
earlier.
Procedure: Jacobs examined the capacity of STM using a digit span test. His sample consisted of 443 females students who were
required to repeat back a string of numbers or letters.
Findings: On average the participants could recall 7.3 letters and 9.3 numbers. Miller therefore concluded that we remember 7+/-2
items, but we can remember more through chunking.
Baddeley (1966)
Aim: Baddeley wanted to see how each memory store coded information.
Procedure: Baddeley split participants into 4 groups, each group had a list of words to remember. Group 1 - acoustically similar
words, Group 2 - acoustically diss-similar words, Group 3 - semantically similar words, Group 4 - semantically diss-similar words.
Findings: On STM participants did worse on acoustically similar words whereas on LTM participants did worse on semantically
similar words.
Conclusion: This suggests that coding is acoustic in STM and semantic in LTM as participants were easily confused.
Outline and Evaluate the MSM (16 marks)
Atkinson and Shiffrin (1968) developed the multi-store model which is a representation of how memory processes work. The
multi-store model is a structural model composed of 3 separate stores the sensory memory, short term memory and long term
memory. Information is linearly passed between these stores and each of these stores are distinct and separate, if one were to
get damaged the other stores would still work. Each of these stores also differs in terms of 3 characteristics coding, capacity
and duration. The sensory memory is the first storage system for incoming information. Information received is raw and
unprocessed and is from environmental stimuli (5 senses). The sensory memory has several stores called sensory registers with
each processing information from a particular sense. The iconic store is where visual images are kept for a short period and
finally, the haptic stores retain a physical sense of touch and internal muscle tension. If the information in the sensory memory is
paid attention to it is transferred to the short term memory. The capacity of the sensory memory is quite large but the duration is
small. The next storage system is the short term memory which receives information that has been paid attention to by the
sensory register, Information in the short term memory has a limited duration of up to 18 seconds and is in a fragile start and wi;
decay very easily if not rehearsed. The capacity of the short term memory is 7+/-2 chunks according to Jacob and Miller's study
so the capacity is limited. Due to the limited capacity information from the STM will disappear if new information comes in also
referred to as displacement. However, if the information is rehearsed and processed deep enough information is passed to the
LTM. The STM codes information acoustically. The last storage system is the long term memory which is potentially a
permanent memory store of information that has been rehearsed for a prolonged time. LTM is believed to have unlimited
duration and capacity. When we want to recall information, it must be transferred back into the STM by retrieval. According to
the multi-store model, none of our memories is rehearsed directly from the LTM. The long term memory codes information
semantically and is based on meaning.
psychologists use theoretical models to simplify the processes underlying memory.
The multi-store model (MSM) of memory: Devised by Atkinson and Shiffrin (1968), was the first cognitive description of memory. It
views information as passing through a series of linear storage systems: The Sensory Register (SR), Short-term Memory (STM)
and Long-term Memory (LTM).
Each stage varies in terms of:
Coding = the format in which the information is kept. Rehearsal Loop
Capacity = the quantity of information that can be stored.
Duration = how long it can be stored for.
Transfer
Attention
Sensory Short-Term Long-Term
Register Memory Memory
MSM =
Retrieval
A summary of the features of each store:
Sensory Register Short-term Memory Long-term Memory
STM capacity
STM duration Coding Sense Specific can be increased
can be
(different stores for Mostly acoustic (by Mostly Semantic (by by chunking
increased by sound) meaning) items together
verbal rehersal. each sense) (Miller 1959).
Capacity Very large capacity Small - 7+/-2 items Potentially unlimited
Duration Breif 1/2 second Short (max 30 seconds) Potentially a lifetime
Research Support
Peterson and Peterson (1959)
Aim: Peterson & Peterson (1959) investigated the duration of short-term memory by conducting a laboratory experiment with a
sample of 24 psychology students.
Procedure: The students had to recall meaningless three-letter trigrams (for example, THG, XWV) at different intervals (3,6,9,12,15
or 18 seconds). To prevent rehearsal the students had to count backwards in threes or fours from a specific number ,until they were
asked to recall the letters.
Findings: Peterson & Peterson found that the longer the interval, the less accurate the recall. At 3seconds, around 80% of the
trigrams were correctly recalled, whereas at 18 seconds only 10% were correctly recalled.
Conclusion: Peterson & Peterson concluded that short –term memory has a limited duration of approximately 18 seconds.
Furthermore, the results show that if we are unable to rehearse information, it will not be passed to long-term memory, providing
further support for the multi-store model and the idea of discrete memory stores
GRAVE: High standardised procedure and it is scientific. Therefore it has high reliability and replicability. However, low ecological
validity as artificial stimuli was used.
, Bahrick (1975)
Aim: Investigated the duration of LTM.
Procedure: Examined 392 American university graduates on their memory for former classmates by asking participants to match
the names of former classmates to pictures in a yearbook photo.
Findings: 60% accuracy for matching names and faces 47 years after graduation.
Conclusion: Memories stored in LTM can last a life time or at least 47 years.
GRAVE: High ecological validity as real-life memories were used however it lacks population validity as we are unable to
generalise to other populations. High temporal validity as the results wouldn’t be the same today due to social media.
Miller (1956) and Jacobs (1887)
While Miller (1956) is commonly cited for his research examining STM, Jacobs (1887) actually conducted similar research 69 years
earlier.
Procedure: Jacobs examined the capacity of STM using a digit span test. His sample consisted of 443 females students who were
required to repeat back a string of numbers or letters.
Findings: On average the participants could recall 7.3 letters and 9.3 numbers. Miller therefore concluded that we remember 7+/-2
items, but we can remember more through chunking.
Baddeley (1966)
Aim: Baddeley wanted to see how each memory store coded information.
Procedure: Baddeley split participants into 4 groups, each group had a list of words to remember. Group 1 - acoustically similar
words, Group 2 - acoustically diss-similar words, Group 3 - semantically similar words, Group 4 - semantically diss-similar words.
Findings: On STM participants did worse on acoustically similar words whereas on LTM participants did worse on semantically
similar words.
Conclusion: This suggests that coding is acoustic in STM and semantic in LTM as participants were easily confused.
Outline and Evaluate the MSM (16 marks)
Atkinson and Shiffrin (1968) developed the multi-store model which is a representation of how memory processes work. The
multi-store model is a structural model composed of 3 separate stores the sensory memory, short term memory and long term
memory. Information is linearly passed between these stores and each of these stores are distinct and separate, if one were to
get damaged the other stores would still work. Each of these stores also differs in terms of 3 characteristics coding, capacity
and duration. The sensory memory is the first storage system for incoming information. Information received is raw and
unprocessed and is from environmental stimuli (5 senses). The sensory memory has several stores called sensory registers with
each processing information from a particular sense. The iconic store is where visual images are kept for a short period and
finally, the haptic stores retain a physical sense of touch and internal muscle tension. If the information in the sensory memory is
paid attention to it is transferred to the short term memory. The capacity of the sensory memory is quite large but the duration is
small. The next storage system is the short term memory which receives information that has been paid attention to by the
sensory register, Information in the short term memory has a limited duration of up to 18 seconds and is in a fragile start and wi;
decay very easily if not rehearsed. The capacity of the short term memory is 7+/-2 chunks according to Jacob and Miller's study
so the capacity is limited. Due to the limited capacity information from the STM will disappear if new information comes in also
referred to as displacement. However, if the information is rehearsed and processed deep enough information is passed to the
LTM. The STM codes information acoustically. The last storage system is the long term memory which is potentially a
permanent memory store of information that has been rehearsed for a prolonged time. LTM is believed to have unlimited
duration and capacity. When we want to recall information, it must be transferred back into the STM by retrieval. According to
the multi-store model, none of our memories is rehearsed directly from the LTM. The long term memory codes information
semantically and is based on meaning.
