Multi-store model (booklet 1) Flashcards
(28 cards)
Coding
Converting raw sensory information into a meaningful form to be processed in memory
Capacity
Maximum amount of information that can be stored
Duration
How long the information (memory trace) can be stored by memory
Describe the multi store model
Atkinson and Shiffrin (1968)
All information enters sensory register
When we pay attention it enters the short term memory
Maintenance rehearsal keeps the memory in short term memory
Elaborate rehearsal moves the memory to long term memory
To recall a memory stored in long term memory it must be retrieved
What does the multi store model of memory suggest?
Memory works as a process where information arriving at the senses must pass through a series of 3 memory stores - sensory register, short term memory, long term memory
Based on the belief we process memory the same way computers process information
Name 2 issues with the multi store model
Oversimplified
Ignores other types of memory eg multiple types of LTM
Describe the sensory register
All stimuli from environment pass into sensory register
Information only lasts for a brief moment unless attention directed to it when it transfers to STM
Coding- separate sensory registers eg iconic store = visual information, echoic store = auditory information
Duration- less than half a second
Capacity- very large, eg over 100 million cells in each eye each storing information
Describe a study of the sensory register
Sperling (1960)
Displayed grid of letters and numbers for 50 milliseconds
Some participants were asked to write down all 12 characters
Others asked to recall only 1 row
When asked for whole thing recall poor - only 5/12 items, 42%
When asked for 1 row - 3/4, 75%
Concluded information decays rapidly in iconic sensory register
What 3 ways can information be coded?
Acoustically - by sound
Semantically - by meaning
Visually - by an image
What was Baddeley’s (1966) aim?
To test if encoding in STM and LTM is acoustic or semantic
Describe Baddeley’s (1966) method
4 groups of participants - 75 people per group (independent groups)
Each group read a list of word 4 times
After given same words in jumbled order and asked to reorder
Group A = acoustically similar words
Group B = acoustically dissimilar words
Group C = semantically similar words
Group D = semantically dissimilar words
Give the STM results of Baddeley’s (1966) study
Immediate recall
Acoustically similar group made more acoustic confusion errors - only 10% put words in correct order
Other groups 60-80% correctly ordered
Concluded main type of coding in STM is acoustic coding
Give the LTM results of Baddeley’s (1966) study
20 minute delayed recall
Semantically similar group made most errors - only 55% recalled accurately
Recall better at 70-85% for other groups
Concluded main type of coding in LTM is semantic coding
Evaluate Baddeley’s (1966) study
✅lab environment- good EV control eg time of day, room so can be confident IV (list of words) affected DV (correct order or not) - high internal validity
❌artificial task - not asked to recall in every day life so lacks ecological validity - results can’t be applied to real life so in real world LTM may not be semantic, STM may not be acoustic, lacks mundane realism so may not be credible
Describe Jacob’s (1887) study on STM capacity
Measured digit span
Researcher reads 4 digits, participant recalls aloud in correct order, if correct researcher reads 5 and so on until incorrect
Indicates individual’s digit span
Found mean span across all P’s was 9.3 digits and 7.3 letters
Describe Miller’s (1956) STM capacity study
Aim - investigate capacity of STM
Method - showed random letter sequences for set time then immediately asked to recall sequence- chain gets 1 letter longer each trial
Results - recalled 7 letters on average, some 2 more, some 2 less
Conclusion - STM capacity 7 plus or minus 2 items
Chunking
A process where a larger number of items are reduced to a smaller number by combining pieces of information into meaningful units
What does chunking do?
Increases STM capacity to more than 7 plus or minus 2
Evaluate Miller’s (1956) STM work
Cowan (2001) concluded STM capacity only about 4 plus or minus 1 chunks so Miller overestimated STM capacity
Give research evidence for STM duration
Peterson and Peterson (1959)
Aim- to investigate duration of STM
Method - P’s asked to remember a sequence of trigrams, asked to recall immediately or after 3,6,9,12,15,18 seconds, during interval asked to count backwards in 3’s to prevent rehearsal
Results- 90% of trigrams recalled after 3 seconds, steadily decreased as retention interval lengthened, only 6% recalled after 18 seconds
Conclusion - duration of STM without rehearsal 18-30 seconds
Evaluate Peterson and Peterson’s study
✅lab environment- good EV control so high internal validity
✅shows importance of rehearsal in memory
❌artificial task - lacks ecological validity, hard to apply/generalise findings
❌individual differences- sample was all psychology students so doesn’t reflect whole population
❌participants may have improved with practice
Give evidence for LTM capacity
Case of Solomon Shereshevsky by Luria (1968)
Newspaper reporter in Moscow
Luria studied him for 30 years
Claimed Shereshevsky’s memory was so perfect he could remember virtually every detail of his life
Luria gave him a long list of numbers, words and nonsense syllables to remember- all recalled perfectly
Luria found no limit to capacity or duration of his memory
Describe Bahrick’s (1975) study
Demonstrates LTM duration is infinite
Showed 400 participants ranging from 17-74 years old a set of photos and list of names, some of which were former school friends
P’s were asked to recall faces + names of former classmates
Those who’d left school within previous 15 years recalled 90% of faces whereas those who’d left 48 years prior recalled 80% of names and 70% of faces
High recall levels suggest LTM duration is indefinite
Evaluate Bahrick’s (1975) study
✅high ecological validity- real people with real classmates so study can be applied/ generalised to real life easily
❌confounding variables eg practice - rehearsal of names may affect recall for example if some still live locally, names retrieved more frequently
