Capacity- How much the store can hold
It can hold 7+/- 2 chunks of information (Jacobs +Miller)
Encoding- How the information is stored
Mainly acounstically (How it sounds) (Baddely)
Duration- How long the information is held
15-30 seconds (Peterson and Peterson)
Jacobs digit span technique (Capacity)
-Pp given a sequence of letters or numbers.
-Had to repeat them in the same order
-3 items at first but increased by 1 each time until the pp could not longer repeat them (:
- It was a repeated measures design
Numbers were remembered better than letters
STM increased with age
8 year olds had average span of 6.6, where it was 8.6 for 19yr olds
Miller found that if we chunk things together we remember more e.g. it was be easier to remember ITV BBC CCTV ABBA than ITVBBCCCTVABBA
Duration- Peterson and Peterson- 3 letter Trigram
-Lab experiment of 24 students told a 3 letter trigram e.g. NME
-They were asked to count backwards to stop rehearsal for either 3,6,9,15 or 18 seconds before recalling trigram.
-This was repeated several times using seperate trigrams
-Pp remembered more after 3.
-At 18secs=10% of trigrams remembered
- Informations decays quickly if rehearsal is prevented
All students so cant generalise
Lacks ecological validity as would do in everday life