Multi-store model of memory Flashcards
Who came up with the Multi store memory model?
- Atkinson & Shiffrin (1968)
What’s the model based on?
- Assumes there are 3 separate memory stores & info is passed between the stores in a linear way
- each memory store differs in duration, encoding & capacity
- The model has an input, process & output
- Info is detected through environmental stimuli passing to the SS then to the STM if attended to & then into LTM if rehearsed
What is the model composed of?
- Sensory store - STM - LTM
- Attention in between sensory & STM
- Transfer in between STM & LTM
- Retrieval from LTM to STM
- Memory passes from STM to LTM
through maintenance rehearsal
What’s the duration, encoding & capacity of the sensory store?
- Duration: 0.5 seconds
- Encoding: Info is processed from senses e.g. iconic (visual), echoic (sound), haptic (touch)
- Capacity: Unlimited
What’s the duration, encoding & capacity of STM?
- Duration: 30 seconds
- Encoding: Acoustic
- Capacity: 7 things +/-2
What’s the duration, encoding & capacity of LTM?
- Duration: Unlimited
- Encoding: Semantic
- Capacity: Unlimited
Research for SS?
- Capacity & Duration: Sperling (1960)
Research evidence for capacity of the sensory store?
What does research show?
- Sperling (1960)
- Studied SS for vision (iconic) & asked Pt’s to recall as many letters they could from a grid of 12 symbols displayed on a screen for 50 milliseconds
- Found: Pt’s could only recall 4 of the symbols before the grid disappeared from their SS, they reported seeing more symbols than they had time to report
- Shows capacity of sensory activity is arguably unlimited
Research for STM?
- Duration: Peterson & Peterson (1959)
- Capacity: Jacobs (1987)
Research evidence for duration of STM?
What does research show?
- Peterson & Peterson (1959)
- Nonsense trigrams (e.g. PXT) were read to Pt’s & Pt’s were asked to count backwards in 3s from a random large 3 digit number in random time limits & then had to recall the trigram
- Found: After 3 second delay there was 90% recall vs 2% recall after 18 seconds
- STM has a limited duration of 18-30 seconds
Research evidence for capacity in STM?
What does research show?
- Jacobs (1887)
- Tested STM capacity on Pt’s presented with long lists of numbers/letters & had to recall them immediately in order
- Found: Capacity for numbers (9.3 items) & letters (7.3 items) for immediate recall
- Supports capacity for STM (7+/-2)
Research evidence for LTM?
- Duration: Bahrick (1975)
- Encoding: Baddeley (1966)
Research evidence for duration in LTM?
What does research show?
- Bahrick (1975)
- Used 392 American ex-High-school students aged between from 15 years/48 after leaving high school
- Pt’s tested by free recall & photo recognition & Pt’s were asked to identify former classmates from 50 photos
- LTM was assessed by comparing Pt’s responses with yearbooks of all students in the year
- Found: Recognition group was 90% (names & faces), declining to 70% names & 80% for faces after 48 years
- Shows LTM is unlimited in duration
Research evidence for encoding in LTM?
What does research show?
- Baddeley (1966)
- Gave Pt’s 4 sets of words: Set 1 (similar sounding), Set 2 (different sounding), Set 3 (similar meaning), Set 4 (different meaning)
- Pt’s struggled to remember set 1 words in STM but not LTM whereas similar meaning words did not affect STM but caused problems for LTM
- Shows LTM relies on semantic encoding
To evaluate memory research studies what 2 things can normally be used in an evaluation point?
- Lacks ecological validity (Peterson & Peterson 1959)
- Useful practical applications (Bahrick 1975)