Psych: The MSM

• Multi-store memory model (MSM)

  Represents how memory is stored, transferred between the different stores, retrieved and forgotten
• Memory stores in the MSM

  • Sensory register
  • Short-term memory
  • Long-term memory
• Sensory register


  • Contains one sub-store for each of the 5 senses
  • Has a huge capacity
  • Has a duration of less than half a second
• Information passes from sensory register to short-term memory


  If we pay attention to it
• Short-term memory (STM)


  • Acoustically encoded
  • Capacity of 7+/- 2 items
  • Duration of 18-30 seconds
• Maintenance rehearsal in STM

  1. Repeat new information to ourselves

  2. Allows information to be kept in STM

  3. Prolonged maintenance rehearsal allows information to pass into long-term memory (LTM)

  4. Lack of rehearsal causes forgetting
• Long-term memory (LTM)


  • Semantically encoded
  • Unlimited capacity
  • Very long duration (over 46 years)
• Retrieval from LTM


  1. Information is transferred back into the STM

  2. Continues to pass through the maintenance loop afterwards
• The MSM does not represent the different types of LTM as it sees LTM as a single, unitary store
• The MSM does not represent that some types of LTM can be retrieved unconsciously whilst others must be retrieved consciously
• Amount of maintenance rehearsal


  Determines likelihood of information passing into LTM
• Craik and Watkins (1973) suggest that it is the type of rehearsal, not just the amount, that is important for transferring information to LTM
• Elaborative rehearsal, making links with existing knowledge, is needed to transfer information from STM to LTM
• Differences between STM and LTM

  • STM is acoustically encoded, LTM is semantically encoded
  • STM has much shorter duration than LTM
• The MSM accurately portrays the qualitative differences between STM and LTM
• The MSM incorrectly represents STM as a single, unitary store
• Evidence suggests there may be multiple types of STM, not just a single store