Multi-store model

• Coding

  The format in which information is stored
• Memory encoding


  The initial learning of information
• Encoding

  1. Transformation of internal thoughts and external events into short term and long-term memory

  2. Information is processed and categorised for storage and retrieval
• Memory encoding is a crucial step in creating a new memory. Memory encoding converts the perceived item or event into a construct that can be stored and recalled later from the brain.
• Types of encoding

  • Visual
  • Acoustic (sounds)
  • Semantic (meanings)
• LTM gets confused when retrieving order of semantically similar words


  It gets distracted by the semantic similarities (the meanings) and muddles them up. It has no problem retrieving acoustically similar words because LTM pays no attention to how the words sound (because sounds aren't encoded acoustically in the LTM).
• Baddeley's research


  1. Gave four 10 word lists to four participant groups

  2. First list: acoustically similar words

  3. Second list: acoustically dissimilar words

  4. Third list: semantically similar words

  5. Fourth list: semantically dissimilar words

  6. Found immediate recall worst for list 1, and recall after 20 minutes worst for list 3
• Short-term memory


  • Capacity is 7 +/- 2 (Miller)
  • Research: Miller (1956) - things come in groups of 7, suggesting we are predisposed to remembering this quantity
  • Research: Jacobs (1887) - mean letter span was 7.3 and mean digit span was 9.3
• Long-term memory


  Has unlimited capacity, as no research has been able to measure a finite number
• Duration of short-term memory

  18-30 seconds
• Peterson and Peterson's research


  1. Showed participants 3-letter trigrams

  2. Participants had to count backwards for a few seconds to stop maintenance rehearsal

  3. Found recall was less than 10% after 18 seconds
• Maintenance rehearsal

  Repeating items over and over to maintain them in short-term memory
• Bahrick's research


  1. Showed old photographs and names to participants aged 17-74

  2. Recall was 90% after 15 years, and still 80% for names after 48 years
• Limitations of the research


  • Baddeley used artificial stimuli rather than meaningful material
  • Jacobs' study was conducted in 1887, lacking adequate control
  • Miller may have overestimated the capacity of STM
  • Peterson and Peterson's study used artificial stimulus material
  • Confounding variables reduce the internal validity of Bahrick's study
  • Peterson & Peterson's study could have forced displacement
• Atkinson & Shiffrin's multi-store model


  Describes how information flows through the memory system
• Multi-store memory model


  1. Memory is made up of three stores linked by processing:

  2. Sensory register - brief duration, high capacity

  3. Short-term memory - acoustically coded

  4. Long-term memory - semantically coded
• Evaluation of the multi-store model


  • Supporting research adds validity to the idea that the STM and LTM are separate stores
  • Incorrectly represents STM as a single, unitary store
  • Craik and Watkins suggest type of rehearsal, not just amount, is important for transfer to LTM