STM and LTM Flashcards
(33 cards)
define coding
- format in which information is stored in the various memory stores
- can be stored acoustically, semantically or visually
describe Baddley’s 1966 study
- STM, LTM, encoding
- gave different lists of words to 4 groups of participants
-2. asked them to recall them in the correct order
what did Baddley conclude about the LTM?
- 1966
- semantically similar words were more difficult to recall after 20 minutes
- so the LTM must rely on semantic encoding
What did Baddely conclude about the LTM’s encoding system (1966)
- semantically similar words were more difficult to recall after 20 minutes
- so the LTM must rely on semantic encoding
Describe Jacobs Digit Span Study 1887
- procedure
- read 4 digits, participant repeats out loud
- if correct, researcher reads out 5 digits and so on until participant makes a mistake
state Jacobs’ findings to his 1887 Digit Span Study
Digits recalled - 9.3
Letters recalled -7.3
explain a weakness of Jacobs’ 1887 Digit Span Study
- time period
- carried out in 1887
- early research often lacked controls
- confounding variables may have had an effect
- could reduce validity
define validity
how well a test actually measures what it was created to measure
explain a strength of Jacobs; 1887 Digit Span Study
- replications
- replications have been carried out and produced similar results
- these had better scientific conditions
- Bapp et al’ (2005) replicated findings, suggesting it was a valid test of the STM
explain a strength of Baddley’s 1966 encoding study
- separated stores
- identified a clear difference between 2 memory stores
- as he founded STM and LTM encoded info differently
- provides evidence the stores are different from each other
- helped support MSM
explain a weakness of Baddley’s 1966 encoding study
- artificial stimuli
- the experiment used artificial stimuli
- word lists had no meaning and had no value in everyday life
- when processing meaningful info, people may use semantic coding
what did Miller conclude about capacity?
- capacity of STM is 7 +/-2 items
- we chunk pieces of info together
explain a weakness of Miller’s chunking theory
- he may have overestimated capacity of STM
- Cowan found lower
- Simon found that the size of chunks impact capacity of STM
- what did Cowan do 2001?
- how did he relate to Miller’s chunking theory
- 2001, found that capacity of STM is only 4+/-1 chunks
- suggests Miller’s estimation was too high
define duration
length of time that information can be stored in the memory
describe Peterson and Peterson’s 1959 study
- STM duration study
-24 students, 8 trials
each student was given a trigram, then a 3 digit number
- had to count backwards from this number until told to stop
(to prevent mental rehearsal)
- each trial told to stop after a certain period (3, 6…18 secs)
what were Peterson and Petersons findings?
- STM duration 1959
- after 3 secs, recall was 80%
- after 18 secs, recall was 3%
- suggested STM duration was 18 secs, unless we rehearse the information
explain a weakness of Peterson and Petersons 1959 STM duration study
- artificial stimuli
- use of artificial material as stimuli
- ppts asked to recall meaningless material
- problematic, doesn’t reflect everyday memory use
- may mean research isn’t useful in understanding STM duration in regular life
describe Bahrick’s 1975 study
- LTM duration
- tested 400 people aged (17-74) on memory of classmates
1. PHOTO RECOGNITION test from yearbook
2. FREE-RECALL, ppts asked to list names from their class
what were Bahrick’s findings for the 1975photo recognition test?
- LTM duration
- within 15 years, accuracy was 90%
- after 48 years, accuracy declined to 70%
what were Bahrick’s findings for the 1975 free recall test?
- LTM duration
- within 15 years, accuracy was 60%
- after 48 years, declined to 30%
what was the conclusion for Bahrick’s 1975 study?
- he found that the LTM’s duration can last a lifetime
explain a strength of Bahrick’s 1975 LTM duration study
- meaningful stimuli
- use of personal memories
- recall rates are lower in studies with artificial stimuli
- use of meaningful memories means that Bahrick’s study has high external validity
