the multi-store model of memory Flashcards
what is the MSM
a representation of how memory works in terms of the stores: sensory register, STM, LTM. it also describes how information is transferred from one store to another
what is the sensory registor
- where stimulus from the environment enters
- aligns with all 5 senses - 5 different stores: 1 for each senses
what are the 2 main stores in the sensory register
- iconic store - visual information coded visually
- echoic store - sound/auditory information coded acoustically
what is the
capacity
duration
encoding
location
of the sensory register
- capacity = unlimited
- duration = 250 milliseconds
- encoding = modality specific
- location = somatosensory area of the brain
what is the ionic store
integrates masses of visual sensory so we see things in a continuous flow and not disjointing images
who investigate the ionic store and what were their findings
- investigated by Sperling (1960)
- presented pps with a matrix of 12 letters arranged in 3 rows for 50 milliseconds. the pps were either asked to recall a particular row or the entire matrix.
- if they were asked to recall the entire matrix, pps could remember 4.32 letters and if they were asked to recall a row, they could remember 3.04 letters.
- this suggests that the moment the matrix disappears the pps have a very clear memory of the image but in the process of recalling the row, the memory has begun to fade
- Sperling suggests that the duration of the iconic store is about 0.5 seconds and the capacity is about 12 pieces.
what is the echoic store
deals with sound based information and represents it acoustically
who investigated the echoic store and what were their findings
- Treisman, 1964
- investigated this store where pps heard a message being played in each ear and were told to shadow it (repeat the message in the other ear). the message was identical but one was slightly delayed.
- they found that the pps only noticed the messages were the same if the interval was 2 seconds or less, suggesting the maximum duration of two seconds in this store
what is the:
capacity
duration
encoding
location
of the STM
- capacity = 7+/- 2 items
- duration = 18-30 seconds
- encoding = acoustically
- location = prefrontal cortex
what is maintenance rehearsal
occurs when we repeat material to ourselves repeatedly. we keep the information in out STMs as long as we rehearse it. if we rehearse it long enough the material passes into the LTM
what is the LTM
the potentially permanent memory store for information that has been rehearsed for a prolonged time
what is the:
capacity
duration
encoding
location
of the LTM
- capacity = unlimited
- duration = unlimited
- encoding = semantically
- location = hippocampus
how does memory move from LTM to STM
through a retrieval cue
AO3: case studfies
- psychologists have also shown that different areas of the brain are involved in STM and LTM from their study of individuals with brain damage, supporting the MSM
- H.M (studied by Scoville and Milner, 1957), found that he had severe epilepsy due to a bicycle accident. H.M had an operation to remove his hippocampus from both sides to reduce his epilepsy.
- they found that after the operation, his STM was fine, however H.M could not make any new LTMs. he still had all his LTM from before the operation but could not make new ones.
- this provides support for the MSM’s notion of separate stores, as HM was unable to transfer information from his STM to LTM.
AO3: LTM involves more than maintenance rehearsal
Craik and Lockhart (1972) suggested that enduring memories are created by the processing you do, rather than through maintenance rehearsal. they gave pps a list of nouns and asked questions that involved deep or shallow processing. they found that pps remembered more words in the task involving deep processing compared to shallow processing. this suggests that the process of rehearsal does not fully explain the process of creating long-term memories. Deep or elaborative processing is also a key part of the process
AO3: there is more than one type of LTM
- there are lot of empirical studies to support how MSM works. controlled lab studies on capacity, duration and coding, support the existence of a short and long term store which is the basis of the MSM. e.g. Beardsley (1997) found that the prefrontal cortex is active during STM but not LTM tasks. Squier et al (1993) found that using PET scans that the hippocampus is much more active in LTM tasks than STM tasks. this is strong evidence which supports the MSM.
- however much of this information comes from lab studies. these lack mundane realism as most of the tasks are artificial however it has a high internal validity.
AO3: the MSM is too simple
the MSM suggest that both the STM and LTM are single ‘unitary’ stores. however, research does not support this. the working memory model and its supporting research shows that working memory (STM) is divided into a number of qualitatively different stores i.e. it isnt just a difference in terms of capacity and duration, but in kind of memory stored there. the same is true for LTM.
research shows there are a number of qualitatively different kinds of LTM, each behaving differently. therefore, this suggests that the MSM may be overly simplistic.
AO3: the primacy/Recency effect
- the Primary/Recency effect can be used to add validity to the MSM
- when remembering list of words we often remember the words and the beginning and end better than the middle
- this is because the words at the beginning have been rehearsed and are transferring into the LTM and words at the end are still in the STM. however words in the middle have been displaced
- this shows how information flows through the MSM but also supports the idea that the STM and LTM are different in terms of their capacity, duration and coding
