HideShow resource information
  • Created by: DanielleJ
  • Created on: 09-04-14 17:01

Short Term Memory- Capacity

Capacity: 7+/- 2 (5,7,9) 


  • Investigated how much info can be stored in STM
  • Found P's can cope reasonably well with 7 dots flashed on a screen but not many more
  • Miller concluded the span of STM is 7 plus or minus 2


  • used the digit span technique to investigate how many digits (letters&numbers) could be stored in memory at any one time
  • he read aloud lists of digits and added one every time
  • jacobs stop reading when P's could recall them 50% of the time
  • he found average for STM: numbers= 9 but letters= 7
1 of 3

Short Term Memory- Duration

Duration: 18 seconds

peterson and peterson:

  • studied 24 university students
  • P's were asked to remember nonsense trigrams
  • Then count back in 3's from a number (eg: 303) until told to stop
  • P's then had to recall the trigrams (the idea of counting back in 3's was to prevent rehearsal)
  • on each trail the time spend counting back varied between 3 and 18 seconds
  • P's remebered around 80% when there was a 3 seconds interval and about 18% when there was a 18second interval
  • this shows P's can remember information for around 20seconds when rehearsal is prevented
2 of 3

Short Term Memory- Encoding

Encoding: Haptic, echoic, and iconic


  • Presented people with visual data
  • asked them to recall the letters they had seen (letters shown for 0.75 of a second)
  • P's asked to recall in order they had be presented in
  • letters sound more alike = more errors
  • this shows info is encoded aqcounsitcally in STM


  • Gave P's 4 lists of words (acoustically similar, acounstically dissimilar, semantically similar and semantically dissimilar) 
  • Halfs of P's were asked to recall words immediently whilst the other half recalled words after 12 minutes
  • people who recalled straigt away = remeber semantically similar better but made more mistakes with acoustically similar
  • this shows info in STM is stored acoustically
3 of 3


No comments have yet been made

Similar Psychology resources:

See all Psychology resources »See all Memory resources »