Multi store model of memory Flashcards
who created the multi store model?
Atkinson and Shiffrin (1968)
Name the three MSM stores.
- sensory register
- short term memory
- long term memory
linear model
information is shown to flow through the system in one direction
passive stores
The stores hold on to information being passed on or lost
coding
the different information types/formats the brain uses to store memory
capacity
how much information can be stored
duration
how long information can be stored before it is lost
Sensory register - coding
Coding of the coding of the sensory register is modality specific (depends on the organ)
sensory register - capacity
large
sensory register - duration
250 millisecond
How can the information from the sensory register move to the short term memory?
attention
short term memory - coding
acoustically (sound)
short term memory - capacity
7+-2 items which was suggested by miller
short term memory - duration
30 seconds
long term memory - coding
semantically (meaning)
long term memory - capacity
unlimited
long term memory - duration
unlimited
Evidence that STM and LTM are separate: Murdock serial position effect (1962)
- asked participants to free recall words in a list
- recall was much stronger for words at the start and the end
- word first heard entering the LTM and being recalled (primacy effect)
- the most recent words were being held by STM and being recalled (recency effect)
Evidence for coding in STM and LTM (Baddley - 1966)
75 ppts divided into 4 groups and each shown 1/4 word lists:
- acoustically similar
- acoustically dissimilar
- semantically similar words
- semantically dissimilar words
Ppts were asked to recall the words in the correct order
Finding for Baddeley (1966) ?experiment
Baddeley concludes that LTM encodes semantically, at least primarily. His earlier experiments suggest STM encodes acoustically.
This is why LTM gets confused when it has to retrieve the order words which are semantically similar: it gets distracted by the semantic similarities and muddles them up. It has no problem retrieving acoustically similar words because LTM pays no attention to how the words sound.
Evidence for capacity of STM (Jacobs - 1887)
- PPTS were given lists of letters or numbers
- PPTS had to recall that list
- It was found that capacity for letters was on average 7 items for letters and 9 for numbers
- this shows that capacity for STM is very limited
Evidence for the duration of the STM ( Peterson and Peterson - 1959)
- ppts were briefly shown a consonant trigram
- ppts were asked to count backward in 3s to stop them from releasing trigrams
- after intervals of 3, 6, 9, 12, and 18 secs ppts were asked to recall the original trigram
- procedure repeated with different trigrams
Findings of the Peterson nd Peterson experiment
- After 18 seconds recall was less than 10%
- this suggests that information can only be held in the STM for a short time before it disappears
Evidence for LTM capacity (wagenaar - 1986)
- created a dairy of over 2400 events during 6 years, including recording who, when, what, and where
- 75% recall of one particular detail after 1 year
- 45% recall after 5 years
- this shows capacity is very large, potentially limitless
Evidence for the duration of the LTM (Bahrick - 1975)
- 392 PPTS aged 17-74 were tested on the memory of old school friends
- recall was 90% after 15 years
- recall was 80% after 48 years
- this suggest the duration of the LTM is very large, potentially limitless
MSM AO3 - inferences
Models of the memory cannot be directly observed so researches have to make inferences on the structure of memory based on behaviour observed during experimentation. These inferences could be incorrect.
MSM A03 - Brain scanning techniques
Evidence: Squire et al (1992) used brain-scanning techniques and found that STM can be associated with activity in the prefrontal cortex and that LTM can be associated with activity in the hippocampus. : This is a strength because it provides biological evidence that the different types of memory are processed by different parts of the brain and that the memory stores are distinct as the multi-store model suggests.
MSM A03 - Murdock
- asked participants to free recall words in a list
- recall was much stronger for words at the start and the end
- word first heard entering the LTM and being recalled (primacy effect)
- the most recent words were being held by STM and being recalled (recency effect)
how many participants were in the Peterson and Peterson experiment?
24 psychology students
Give an example of one of the trigrams in Peterson and Peterson’s study?
TGH and CLS
Independent variable of the Peterson and Peterson’s study?
the time interval between the experimenter saying the trigram and the participant recalling the trigram
dependent variable of the Peterson and Peterson’s study?
The dependent variable was the number of trigrams correctly recalled by the participants after every trial.
