Memory Flashcards
What is short term memory?
- information that we process and recall straight away
- stores the information we are currently aware of
What is coding?
the format in which the information is stored in memory
What happens when we experience sensory information?
it stays there just long enough to decide if we should process it further. If we attend to it, it will transfer to our STM
What is long term memory?
- the permanent memory store
- continual storage of information which is largely outside of our awareness but can be recalled
What type of coding is in the LTM?
semantic
What does capacity mean?
the amount of information held in a memory store
What does duration mean?
the length of time information can be held in memory
What is the capacity of STM?
5-9 items
What is the capacity of LTM?
unlimited
What is the duration of STM?
18-30 seconds
What is the duration of LTM?
potential lifetime
What is Miller’s Magic number?
7
What did Miller argue?
- he argued that most things come in 7s
- he concluded that on average we can recall 7 items + or - 2
- we can remember more as long as we information down in to 5-9 manageable chunks
- he discovered we can remember 5 words as easy as 5 letters
What is the digit span test?
- developed by Jacobs in 1887
- the researcher gives a number of digits and the participant has to recall them in order
- the researcher then increases the amount by 1 digit and the ppts has to recall them again until they cannot recall the correct order
- this determines their digit span
What were the results of the digit span test?
- 3 items for numbers
7. 3 for letters
What are strengths of the digit span test?
- quick and easy to do (straightforward)
- tells us capacity of STM
- replicable
- supports multi store model of memory
What are weaknesses of the digit span test?
- not applicable to real life (random sequence of number/letters -> controlled conditions
What was Baddeley’s aim?
to investigate whether coding in STM and LTM is acoustic or semantic (meaning)
What was Baddeley’s method?
he gave the ppts one of four word lists and asked them to memorise them
- list A - acoustically similar
- list B - acoustically dissimilar
- list C - semantically similar
- list D - semantically dissimilar
they were asked to recall them either immediatley of after 20 minutes
What were Baddeley’s findings?
List A was recalled the worst immediately (10% recalled)
List C recalled the worst after 20 minutes
What were Baddeley’s conclusions?
List A recalled worst immediately - suggests acoustic confusion in STM
List C recalled worst after 20 mins - semantic confusion in the LTM
Therefore, STM tends to be coded acoustically and LTM is coded semantically
What are the strengths of Baddeley’s research?
- seperate memory stores - identified a clear difference between two memory stores
What are the weaknesses of Baddeley research?
Artificial stimuli - no personal meaning to the participants
What was Peterson and Peterson’s aim?
1959
duration of STM
What was Peterson and Peterson’s method?
nonsense trigrams, counting backwards in 3s from a 3 figure number to reduce rehersals and increased the time by 3 seconds each time
What were Peterson and Peterson’s results?
90% recalled correctly after 3 seconds
10% correct recall after 18 seconds
What was Peterson and Peterson’s conclusion?
without rehersal, STM is probably less than 18 seconds
What was Bahrick’s yearbook study?
- he studies 392 American ppts between 17 and 74
- obtained their yearbooks from high school
- tested their recall in various ways: photo recognition and free recall
What were Bahrick’s results?
ppts tested within 15 years of graduation were 90% accurate in photo recognition
after 48 years, recall declined to 70% for photo recognition
free recall was less accurate than photos: 60% after 15 years and 30% after 48 years
shows that LTM may last up to a lifetime for some material
What are strengths of Bahrick’s study?
- experimental support
- high ecological validity
- real life memories
What are the weaknesses of Bahrick’s study?
- recognition not recall
- lacked important controls (may be friends)
- emotional significance
What was Sperling’s study?
- ppts saw a grid of digits for 50 milliseconds
- they were asked to write down all 12 items or they were told after which row to recall
What were Sperling’s results?
- 75% for one row (3 letters)
- 42% for the whole grid (5 letters)
suggests that sensory memory cannot hold information for long and it decays rapidly in the sensory store - supports the existence of a sensory store
What is the multi-store model of memory?
Maintenance rehearsal
| retrieval
environmental stimuli -> sensory register -> attention -> STM LTM
rehearsal
| |
decay forgetting