Coding, Capacity, Duration Flashcards
What is capacity of STM
7 items +/-2
George Miller
Digit span. More digits added every time. Most could recall numbers up to 7 digits but not many more. (sometimes a bit more sometimes a bit less)
Capacity of LTM
Unlimited
Duration of STM
Less than 18 Seconds
How is duration of STM measured
Ppt given a consonant syllable and a 3 digit number
Asked to recall syllable after an interval of up to 18 seconds.
During this 18 seconds they had to count down from their 3 digit number
90% correct after 3 seconds
20% after 9 seconds
2% AFTER 18 SECONDS
Duration of LTM
Potentially Unlimited
Adults tested on remembering classmates from pictures 15 and 48 years after graduation.
Gradually got worse over time but free recall never reached 0%
Which type of memory is it HARD to remember ACOUSTICALLY similar words in?
STM
Which type of memory is it HARD to remember SEMANTICALLY similar words in?
LTM
What can cause individual differences in the capacity of STM?
Jacobs found that recall (digit span) increased with age.
8 year olds could remember 6.6 digits
19 year olds could remember 8.6 digits
Therefore
What is a criticism of the research investigating STM capacity?
Millers original findings have not been replicated.
Cowan carried out research and found that the limit was four ‘chunks’ of information.
This means that the lower end of Millers range (7-2=5) is more likely to be the case.
What is a criticism of the research investigating STM duration?
It is artificial.
Trying to memorise syllables doesn’t replicate every-day activities.
In every-day life, the things we are trying to remember are usually meaningful.
However, it may still be useful as we do still need to remember some things this is relevant to, such as phone numbers or addresses.
What is another criticism of Peterson’s study
Did not measure what it set out to measure.
Ppts in the study were also counting back numbers in their STM, which may ‘overwrite’ the syllables.
The forgetting in this study was therefore due to displacement, and not decay.
What is the issue with STM and Coding
STM MAY NOT JUST BE ACOUSTIC
Brandimote found that ppts used visual coding if given a visual task, where verbal rehearsal was prevented
Other research has shown STM uses a semantic code
What is the issue with LTM and Coding
LTM MAY NOT JUST BE SEMANTIC
Frost showed that long term recall was related to visual coding too.
Nelson and Rothbart found evidence of acoustic coding in LTM
