Multi-Store Model AO1

• Sensory Register Coding


  Echoic (auditory) and Iconic (visual) memory (attention)
• Short-Term Memory Coding


  Acoustic (sound)
• Long-Term Memory Coding


  Semantic (concept and meaning in relation to context)
• Coding for STM and LTM


  Acoustic, Semantic
• Sensory Register Capacity and Duration


  • Limited capacity
  • 1.5-2 seconds duration
• Short-Term Memory Capacity and Duration


  • Limited capacity (7±2 items)
  • 18-30 seconds duration approximately
• Long-Term Memory Capacity and Duration


  • Unlimited capacity
  • Lifetime duration
• Sperling (1960) procedure


  1. Presented participants with a set of 12 letters arranged in a matrix of 3 rows

  2. Displayed for approximately 1/20th of a second

  3. Asked to recall immediately after

  4. Variation with high/medium/low pitched tone indicating which row to recall
• Baddeley (1966) procedure


  1. 72 participants asked to recall 10 words and the order they are presented in, which were displayed for 3 seconds each

  2. Independent variable had two levels: acoustically similar words versus dissimilar words; semantically similar words versus dissimilar words

  3. Learning phase separated from testing phase with an interference test, involving hearing and writing numbers

  4. Testing phase consisted of recall of the words and the order they were presented, repeated four times; after fourth trial a break and unrelated interference task was complicated, followed by surprise recall
• Miller (1956) and Jacobs (1887) procedure

  Participants repeat back a string of numbers or letters (except 'W' and '7': two syllables) in the same order, each gradually increasing until participants could no longer recall the sequence
• Peterson and Peterson (1959) procedure

  1. 24 participants recall nonsensical three-letter trigrams, presented in intervals of 3, 6, 9, 12, 15, or 18 seconds for each of the 6 trials

  2. After hearing trigram, participants were asked to count backwards in 3s or 4s from a specified random digit to prevent rehearsal
• Bahrick et al. (1975) procedure


  1. 392 American university graduates (17-74) asked to recall names of individuals from their yearbook photos, or were given a list of names to match to the photos

  2. Classes of over 90 students

  3. Participants asked to rate their confidence levels after answering in each trial
• Free recall

  4-5 out of 9 letters recalled with 33-40% accuracy
• Recall of a particular row

  3-4 letters recalled with 74-100% accuracy
• Variation of the study

  1. Recall of all letters if the tone was sounded 1/3 of a second following the display of letters

  2. Recall declines drastically after this
• Participants could recall the information as long as they paid attention to the pertinent row before the memory of the letters decayed
• Acoustically similar words harder to recall than acoustically dissimilar words
• Semantically similar words harder to recall than semantically dissimilar words
• When assessing the STM

  1. Trials before the break showed worse performance for acoustically similar words

  2. Trials 1-3 were worse for semantically similar words
• Miller's notion of 7±2 items

  Participants averaged 7.3 to 9.3 words
• Easier to recall


  • Numbers than letters
• Trigrams correctly recalled after 3, 6 and 18 seconds

  3 seconds: 80%

  6 seconds: 50%

  18 seconds: less than 10%
• After 15 years


  Free recall was 60%, and photo recognition was 90%
• After 40 years


  Free recall was 30%, and photo recognition was 80%
• Sperling (1960) Findings

  • Free recall: 4-5 out of 9 letters recalled with 33-40% accuracy

  • Recall of a particular row: 3-4 letters recalled with 75-100% accuracy

  • Variation of the study showed recall of all letters in the row if the tone was sounded within ⅓ of a second following the display of the letters; after ⅓ of a second, recall declined drastically

  • Suggests that participants could recall the information as long as they paid attention to the pertinent row before the memory of the letters decayed
• Baddeley (1966) Findings

  • Acoustically similar words harder to recall than acoustically dissimilar words

  • Semantically similar words harder to recall than semantically dissimilar words

  • When assessing the STM, trials before the break showed worse performance for acoustically similar words; STM coded acoustically as trials 1-3 were worse for semantically similar words
• Miller (1956) and Jacobs (1887) Findings

  • Jacobs found that participants averaged 7.3 to 9.3 letters, supporting Miller’s notion of 7±2 items

  • Easier to recall numbers than letters
• Peterson and Peterson (1959) Findings

  • Correctly recalled after 3 seconds: 80%

  • Correctly recalled after 6 seconds: 50%

  • Correctly recalled after 18 seconds: less than 10%
• Bahrick et al., (1975) Findings

  • After 15 years: free recall was 60%, and photo recognition was 90%

  • After 40 years: free recall was 30%, and photo recognition was 80%
• Who proposed the MSM?

  Atkinson and Shiffrin (1968)
• Draw how information processing occurs in the MSM

  AO1