MEMORY
Coding capacity and duration research
Short term memory -
Coding - Acoustic - way it sounds.
Study - Baddeley - gave ppts a set of words that were either acoustically similar or
acoustically dissimilar - independent groups design - had to recall words immediately - had
problems recalling similar words indicating the STM needs words to sound different in order
to remember them.
Evaluation - Baddeley’s research has been criticised for ignoring other methods of STM
coding (e.g. visual) and furthermore the use of an independent groups design means
individual differences in memory may have undermined the internal validity of the study.
Capacity - 7+ or -2 items. Can be increased by chunking. Increases with age.
Study - Jacobs - presented ppts with strings of letters or digits and had to repeat them back
in the same order - increased until the ppts failed to recall the sequence correctly. Found
that the mean span for the digits was 9.3 and mean for letters was 7.3
Evaluation - The task given to do in this research is artificial and it lacks ecological validity-
it is not something you would do in everyday life and it has been argued that meaningful
information may be recalled better.
Duration - around 20 seconds.
Study - Peterson and Peterson. Asked 24 students to take part in eight trials - on each trial
they were ask to recall a trigram and then were asked to count backwards in threes from a 3
digit number. The trials gradually got longer (3,6,9) before they recalled them back. After 3
seconds, ppts could recall 80% but after 18 seconds, only 10% of trigrams could be recalled.
Evaluation - lacking ecological validity. It was a lab based experiment that gave participants
artificial tasks to complete. Furthermore, it has been argued that the repeated measures
design of this study may have led participants to get the many different trigrams confused
rather than any lack of ability to recall being purely due to limited STM duration.
Long term memory -
Coding - semantically - based on meaning.
Study - Baddeley - gave ppts a set of words that were either semantically similar or
semantically dissimilar - independent groups design - had to recall words after a 20 minute
task - patterns of confusion between similar words - LTM relies on semantic coding.
Evaluation - ignored other types of LTM. individual differences.
Duration - potentially a lifetime.
Study - Bahrick - 392 ppts - 17 - 74 yrs of age. Highschool yearbooks were obtained from
the ppts or from their schools and recall was tested either - photo recognition of 50 photos,
or free recall test where they recalled all the names of their graduating class.
Within 15 yrs of graduating - 90%.60%. After 48 yrs - 70%, 30%
Evaluation - This study has the advantage of being high in ecological validity, and therefore
it can be argued that it offers us an accurate insight into the duration of LTM.
However, there is a lack of control of extraneous variables - there is no control over whether
the participants had regularly re- visited their year books since leaving high school as
clearly this would refresh their memory of their classmates meaning Bahrick wasn’t actually
, measuring the duration of LTM after all.
Multi Store Model
Atkinson and Shriffins model explains how information is processed and stored in our brain.
Structural and linear model of memory.
Sensory register -
- Codes all our senses.
- Different stores code different senses.
- Iconic store codes visual stimuli
- Echoic store codes auditory stimuli.
- Capacity is very large.
- Passed onto STM via process of attention, any not payed attention to is decayed or
displaced.
Short term memory -
- Duration is up to 30 seconds.
- Capacity is 7+ or -2 items.
- Coding is acoustic (based on the way it sounds)
- Maintenance rehearsal keeps information within stm, elaborative rehearsal moves it
onto the ltm.
- Any material not rehearsed will be decayed or displaced.
Long term memory -
- Duration is up to a lifetime.
- Capacity is unlimited.
- Coding is semantic (based on meaning)
- Material can be retrieved back to stm when needed in relation to a cue.
- Never forgotten, just cannot be found at that point, known as retrieval failure.
A03:
ONE STRENGTH of the MSM is that it is supported by research. Using a cognitive
neuroscience technique to scan the brain, Talmi et al gave participants 12 items to
remember and then asked them to recall words from the beginning (using LTM) or the end
(using their STM). They found that an area of the temporal lobe of the brain was used for
the long term task and an area of the parietal lobe was used for the short term task. These
findings lend to the support that there is an existence of separate stores.
HOWEVER, A WEAKNESS of the MSM is that the description of the STM is too simple.
Further models such as the WMM argue that the stm is not a unitary store but actually
divided up into a number of stores that can process different forms of memory and code
different pieces of information e.g visual and auditory simultaneously. Indeed Shallice and
Warrington studied a man called KF whose short term memory was damaged but was still
able to process visual information whilst struggling to process verbal. This shows that the
MSMs description of the STM does not accurately explain the complexity of this store.
HOWEVER, A WEAKNESS of the MSM is that the description of the LTM is too simple.
Research has demonstrated that that the LTM is not a unitary store as there a different kinds
of LTM such as episodic (life experiences), semantic (the meaning of words and social
Coding capacity and duration research
Short term memory -
Coding - Acoustic - way it sounds.
Study - Baddeley - gave ppts a set of words that were either acoustically similar or
acoustically dissimilar - independent groups design - had to recall words immediately - had
problems recalling similar words indicating the STM needs words to sound different in order
to remember them.
Evaluation - Baddeley’s research has been criticised for ignoring other methods of STM
coding (e.g. visual) and furthermore the use of an independent groups design means
individual differences in memory may have undermined the internal validity of the study.
Capacity - 7+ or -2 items. Can be increased by chunking. Increases with age.
Study - Jacobs - presented ppts with strings of letters or digits and had to repeat them back
in the same order - increased until the ppts failed to recall the sequence correctly. Found
that the mean span for the digits was 9.3 and mean for letters was 7.3
Evaluation - The task given to do in this research is artificial and it lacks ecological validity-
it is not something you would do in everyday life and it has been argued that meaningful
information may be recalled better.
Duration - around 20 seconds.
Study - Peterson and Peterson. Asked 24 students to take part in eight trials - on each trial
they were ask to recall a trigram and then were asked to count backwards in threes from a 3
digit number. The trials gradually got longer (3,6,9) before they recalled them back. After 3
seconds, ppts could recall 80% but after 18 seconds, only 10% of trigrams could be recalled.
Evaluation - lacking ecological validity. It was a lab based experiment that gave participants
artificial tasks to complete. Furthermore, it has been argued that the repeated measures
design of this study may have led participants to get the many different trigrams confused
rather than any lack of ability to recall being purely due to limited STM duration.
Long term memory -
Coding - semantically - based on meaning.
Study - Baddeley - gave ppts a set of words that were either semantically similar or
semantically dissimilar - independent groups design - had to recall words after a 20 minute
task - patterns of confusion between similar words - LTM relies on semantic coding.
Evaluation - ignored other types of LTM. individual differences.
Duration - potentially a lifetime.
Study - Bahrick - 392 ppts - 17 - 74 yrs of age. Highschool yearbooks were obtained from
the ppts or from their schools and recall was tested either - photo recognition of 50 photos,
or free recall test where they recalled all the names of their graduating class.
Within 15 yrs of graduating - 90%.60%. After 48 yrs - 70%, 30%
Evaluation - This study has the advantage of being high in ecological validity, and therefore
it can be argued that it offers us an accurate insight into the duration of LTM.
However, there is a lack of control of extraneous variables - there is no control over whether
the participants had regularly re- visited their year books since leaving high school as
clearly this would refresh their memory of their classmates meaning Bahrick wasn’t actually
, measuring the duration of LTM after all.
Multi Store Model
Atkinson and Shriffins model explains how information is processed and stored in our brain.
Structural and linear model of memory.
Sensory register -
- Codes all our senses.
- Different stores code different senses.
- Iconic store codes visual stimuli
- Echoic store codes auditory stimuli.
- Capacity is very large.
- Passed onto STM via process of attention, any not payed attention to is decayed or
displaced.
Short term memory -
- Duration is up to 30 seconds.
- Capacity is 7+ or -2 items.
- Coding is acoustic (based on the way it sounds)
- Maintenance rehearsal keeps information within stm, elaborative rehearsal moves it
onto the ltm.
- Any material not rehearsed will be decayed or displaced.
Long term memory -
- Duration is up to a lifetime.
- Capacity is unlimited.
- Coding is semantic (based on meaning)
- Material can be retrieved back to stm when needed in relation to a cue.
- Never forgotten, just cannot be found at that point, known as retrieval failure.
A03:
ONE STRENGTH of the MSM is that it is supported by research. Using a cognitive
neuroscience technique to scan the brain, Talmi et al gave participants 12 items to
remember and then asked them to recall words from the beginning (using LTM) or the end
(using their STM). They found that an area of the temporal lobe of the brain was used for
the long term task and an area of the parietal lobe was used for the short term task. These
findings lend to the support that there is an existence of separate stores.
HOWEVER, A WEAKNESS of the MSM is that the description of the STM is too simple.
Further models such as the WMM argue that the stm is not a unitary store but actually
divided up into a number of stores that can process different forms of memory and code
different pieces of information e.g visual and auditory simultaneously. Indeed Shallice and
Warrington studied a man called KF whose short term memory was damaged but was still
able to process visual information whilst struggling to process verbal. This shows that the
MSMs description of the STM does not accurately explain the complexity of this store.
HOWEVER, A WEAKNESS of the MSM is that the description of the LTM is too simple.
Research has demonstrated that that the LTM is not a unitary store as there a different kinds
of LTM such as episodic (life experiences), semantic (the meaning of words and social
