STM (MSM) Flashcards
What is the capacity of the STM?
7+/-2
What is the coding of the STM
acoustic
(coded through sound)
What is the duration of the STM
18-30 seconds
What was the aim if Millers study
to investigate the capacity of the STM
What was the method of Millers study
used digit span technique
* ppts heard a list of numbers and immediately tried to recall them in order
What were the results of Millers study?
found that the span of STM was 7+/-2.
Also found that when people chunk things together they can remember more
What was the conclusion of Millers study?
capacity of STM IS 7+/-2
What was the aim of Peterson and Petersons study
investigate duration of STM
What was the method of Peterson and Petersons study?
(P) 24 ppts presented with a constant trigram (three letters that dont form a recognisable word)
(E) Rehearsal was prevented by asking them to count backwards in threes from a specific number
(E) After intervals of 3,6,912,15 or 18 seconds to over 30 seconds ppts were asked to stop counting and repeat the trigram
What were the results of Peterson and Petersons study?
after 3 seconds delay there was 80% recall, after 18 seconds there was 10% recall and after 30 seconds no trigrams were recalled
What is a strength of Peterson and Peterson study?
high control
What is a limitation of Peterson and Peterson study?
low ecological validity
Evaluate high control as a strength of Peterson and Peterson study?
(P) lab experiment therefore it can establish cause and effect
(E) had high control over extraneous variables, ppts were all given the same standardised instructions. we fan be confident that the IV affected the DV
(E) strength as results are unlikely to be affected by confounding variables so we can be confident that the conclusion has high internal validity
Evaluate low ecological validity as a limitation of Peterson and Petersons study?
(P) low ecological validity
(E) ppts were presented with a trigram and recalling it is an artificial and simple task that doesn’t test the complexity of memory
(E) limitation as results can’t be generalised to real life and may not provide externally valid support to their theory
What is a strength of research into the STM
conducted with lab experiments
What is a limitation of research into the STM
individual differences
Evaluate the individual differences as a limitation of research into the STM
(P) the claim that it holds 5-9 items may have individual differences in memory capacity such as age
(E) Jacobs found that the digit span increased steadily with age
An 8 year old could remember avg, 6.6 digits whereas a 19 year old could remember avg. 8.6 digits. He also found that people found it easier to recall numbers than letters. Avg. span for letters was 7.3 and numbers was 9.3
(E) limitation because the assumption that ALL individuals STM holds 5-9 items is oversimplification and may not be generalised to how everybody’s STM works
