Multi-store model of memory

• Main points

  The MSM was created by Atkinson and Shiffrin as the first cognitive explanation for memory, believing information flows through a series of storage systems in a linear fashion.
• sensory register

  encoding- from our 5 senses (modality specific)

  capacity- very large

  duration- 0.5 seconds
• short term memory

  encoding- acoustically

  capacity- 5-9 items but can improve this through chunking

  duration- 18-30 seconds
• long term memory

  encoding- semantic

  capacity- unlimited

  duration- up to a lifetime
• The process of MSM

  
  

  • Works in a linear fashion
  • information we pay attention to goes into the STM from the sensory register.
  • It’s stored in the STM until it is repeatedly rehearsed, where it goes into the LTM.
  • When we want to remember our LTM’s, we retrieve it back into our STM
• Evaluation 1- research support

  POINT- One strength of the MSM is that there is supporting evidence

  EVIDENCE- A case study of Clive Wearing, who had encephalitis, found that he has an impaired duration in his STM of 7 seconds. He has not been able to transfer any new LTM since the illness.

  EXPLAIN- The MSM claims memory is linear, so if information was to go to the LTM, it would also have to pass through the sensory register and STM. For Clive, as his STM is damaged, he cant make LTM’s.

  LINK- Supporting the MSM as a linear fashion, making it more valid.
• Evaluation 2- contradicting evidence

  POINT- However, there is evidence to contradict the MSM

  EVIDENCE- Patient KF was injured in a motorcycle accident, and found that his LTM was normal, but his STM was damaged. He found he could only remember 2 items/ chunks, compared to the usual 5-9.

  EXPLAIN- The MSM claims that information works in a linear fashion, so if the STM was damaged, the LTM would consequently be too. however, KF’s LTM was not damaged.

  LINK- Therefore, this evidence contradicts the claim and decreases the validity of the MSM.
• Evaluation 3- oversimplifed

  POINT- Another limitation is that the MSM is oversimplified.

  EVIDENCE- Evidence from the Working memory model, who suggested more than 1 STM store and Tulving, who suggested there were 3 LTM stores instead of 1; semantic, acoustic and episodic, is not displayed in the MSM.

  EXPLAIN- Therefore, the MSM is oversimplified, as it doesnt explain how different memories are allocated to different stores

  LINK- and is thus the validity is decreased.
• Short/ long term mem coding research support.

  • baddeley
  • Ppts given 4 sets of words to recall in order
  • set 1- sounding similar words
  • Set 2- sounding dissimilar
  • Set 3- similar meaning
  • Set 4- different meaning
  • STM findings- after recalling it instantly, made more mistakes on sounding similar words
  • LTM findings, after recalling it longer, made more mistakes on meaning similar words
• Short term mem capacity research support

  • read list of words/ numbers and immediately recalled
  • Increased the list until recall was only 50%
  • Found difference in recall between letters and numbers: 9 numbers, 7 letters
• short term mem duration capacity research support

  • Peterson and Peterson told ppts to remember trigram of 3 constonants
  • asked to recall after a delay every 3 seconds
  • during this time, ppts asked to count backwards in 3s from 36.
  • found duration stm was 18-30 seconds
• long term mem duration research support

  • bahrick tested ppts memory on the names and faces from high school year book
  • found 15years since- 90% accurate with photo recognition
  • found 48 years since— 70% accurate with photo recognition
  • Found 15 years since- 60% accurate with free recall
  • Found 48 years since- 30% accurate with free recall