Memory
Duration:
Peterson and peterson:
Showed ppts 3 consonants and asked to recall them at 3, 6, 9,12, 18 seconds. Counting backwards during intervals:
interference/ prevent rehearsal. 3 seconds: 90% recalled accurately.18 seconds: 10% recalled accurate.
Bahrick:
392 ppts in Ohio asked to list names of ex classmates from free recall test. Within 15 years later, 60% accurate free
recall. After 30 years, free recall 30%. After 48 years name recognition: 80%. Picture: 40%
Capacity:
Jacobs
Digit span: ppts shown string of letters. Repeated back until fully learnt and numbers/ letters increased. Average was
7 letters 9 digits. Concluded STM has storage of 5-9 items
Miller:
Capacity = 7±2. Chunking increases capacity
Coding:
Coding is the way information is stored / processed into memory, eg acoustic, semantic.
STM - Try to keep info active by repeating it to ourselves (acoustic)
LTM - Semantic. Useful to cite words in terms of meaning than what they should look like.
Baddeley:
Ppts given 4 sets of words, acoustically dissimilar. Semantically dissimilar. Independent group design. Asked to
recall either immediately or after 20 minutes.
Ppts had problems with acoustically recalling immediately (coded by STM)
Ppts had problems with semantically recalling after 20 minutes (by LTM). Confusion between similar words.
Multi Store Model: Atkinson & Shiffrin
Structural model composing of 3 separate stores with info passing between stores in a linear way. The sensory
memory has stores called sensory registers, processing info from a particular sense. The iconic register
processes vision, echoic register process sound. SR is not under cognitive control and is first storage system for
incoming info. Info received is unprocessed and SR has large capacity however duration is milliseconds unless
given attention in which it’ll move to STM. Rehearsal maintains info in the STM however still vulnerable to being
forgotten due to limited duration (decay) or displaced by new incoming information due to limited capacity
(displacement). If rehearsed processed deep enough through elaborative/ maintenance rehearsal the info then
passes to LTM which has unlimited capacity and unlimited duration. While the LTM encoding is mainly semantic
and based on meaning, STM encoding is acoustic with capacity of 7 ± 2 items and duration of 18s. Retrieval info
from LTM occurs through info passing back through the STM..
Evaluation:
● One strength for MSM is there is research support from a case study. HM underwent brain surgery to reduce
epilepsy. Hippocampus removed both sides, LTM never improved. Couldn’t recall what he ate for dinner the
same day but performed well on tests of immediate memory (STM). Possible to damage one store while
other intact. Support: both stores unitary independant. However, it’s based on a case study which doesn’t
represent a targeted population due to individual differences, thus lacking population validity and decreasing
its credibility.
● The MSM argued to be oversimplifying memory structures/ processes. For example, Shallice highlighted
this with case study KF who suffered brain damage resulting difficulty with verbal info in STM but normal
ability with visual info. Highlights how STM not single store as MSM suggests causing it to be reductionist
model lacking internal validity
● Flashbulb memories undermine the importance of rehearsal. These are traumatic events which can be
recalled accurately even though this material is not rehearsed. Therefore lacks internal validity because it is
maintained in the LTM without the use of maintenance rehearsal, causing the model to be incomplete.
Duration:
Peterson and peterson:
Showed ppts 3 consonants and asked to recall them at 3, 6, 9,12, 18 seconds. Counting backwards during intervals:
interference/ prevent rehearsal. 3 seconds: 90% recalled accurately.18 seconds: 10% recalled accurate.
Bahrick:
392 ppts in Ohio asked to list names of ex classmates from free recall test. Within 15 years later, 60% accurate free
recall. After 30 years, free recall 30%. After 48 years name recognition: 80%. Picture: 40%
Capacity:
Jacobs
Digit span: ppts shown string of letters. Repeated back until fully learnt and numbers/ letters increased. Average was
7 letters 9 digits. Concluded STM has storage of 5-9 items
Miller:
Capacity = 7±2. Chunking increases capacity
Coding:
Coding is the way information is stored / processed into memory, eg acoustic, semantic.
STM - Try to keep info active by repeating it to ourselves (acoustic)
LTM - Semantic. Useful to cite words in terms of meaning than what they should look like.
Baddeley:
Ppts given 4 sets of words, acoustically dissimilar. Semantically dissimilar. Independent group design. Asked to
recall either immediately or after 20 minutes.
Ppts had problems with acoustically recalling immediately (coded by STM)
Ppts had problems with semantically recalling after 20 minutes (by LTM). Confusion between similar words.
Multi Store Model: Atkinson & Shiffrin
Structural model composing of 3 separate stores with info passing between stores in a linear way. The sensory
memory has stores called sensory registers, processing info from a particular sense. The iconic register
processes vision, echoic register process sound. SR is not under cognitive control and is first storage system for
incoming info. Info received is unprocessed and SR has large capacity however duration is milliseconds unless
given attention in which it’ll move to STM. Rehearsal maintains info in the STM however still vulnerable to being
forgotten due to limited duration (decay) or displaced by new incoming information due to limited capacity
(displacement). If rehearsed processed deep enough through elaborative/ maintenance rehearsal the info then
passes to LTM which has unlimited capacity and unlimited duration. While the LTM encoding is mainly semantic
and based on meaning, STM encoding is acoustic with capacity of 7 ± 2 items and duration of 18s. Retrieval info
from LTM occurs through info passing back through the STM..
Evaluation:
● One strength for MSM is there is research support from a case study. HM underwent brain surgery to reduce
epilepsy. Hippocampus removed both sides, LTM never improved. Couldn’t recall what he ate for dinner the
same day but performed well on tests of immediate memory (STM). Possible to damage one store while
other intact. Support: both stores unitary independant. However, it’s based on a case study which doesn’t
represent a targeted population due to individual differences, thus lacking population validity and decreasing
its credibility.
● The MSM argued to be oversimplifying memory structures/ processes. For example, Shallice highlighted
this with case study KF who suffered brain damage resulting difficulty with verbal info in STM but normal
ability with visual info. Highlights how STM not single store as MSM suggests causing it to be reductionist
model lacking internal validity
● Flashbulb memories undermine the importance of rehearsal. These are traumatic events which can be
recalled accurately even though this material is not rehearsed. Therefore lacks internal validity because it is
maintained in the LTM without the use of maintenance rehearsal, causing the model to be incomplete.
