Multi store model of memory

• Atkinson and Shiffrin (1968) Multi-Store Model of Memory, they argued that STM and LTM is distinct memory stores. Memory is a process. The information we learn passes through a number of stores from Sensory Register, Short Term Memory, and Long Term Memory. It also describes how information is transferred, how it is remembered, and how it is forgotten.
• Encoding = The process of moving information from short term memory to the long term memory Retrieval = Remembering and bringing back information stored in ‘long term memory’ to now Storage = The creation of permeant record of info Attention – to get information from the sensory memory to the STM. Rehearsal – to keep information in the STM or transfer it to the LTM
• MSM: Sensory Register This is where sensory stimuli from the environment is stored, but only for a duration of approximately half a second before it is forgotten. Coding – Each store is modality specific. For example, the store coding for visual information is iconic and echoic for sounds. Capacity – Very large/unlimited Duration - Very brief, about second (250 milliseconds) Very little of what goes through our sensory register moves through to our memory system, unless we pay attention to it
• MSM: Short￾term memory (STM) • If attention is paid to a stimulus, it will enter STM. • Coding - Information is coded acoustically • Capacity – STM has limited capacity, there is a capacity between 5 and 9 items - (7+/- 2) • Duration - Around 18 - 30 seconds unless the information is rehearsed • STM is in a fragile state and so information will decay if maintenance rehearsal (repetition) does not occur, the information is forgotten, and lost from short term memory through the processes of displacement
• MSM: Long term memory (LTM) If information is rehearsed for a longer period of time, it will transfer to LTM • Coding - Information is coded semantically • Capacity - LTM has a potentially unlimited capacity • Duration - A lifelong duration When we want to recall information from the LTM, it has to be transferred back into the STM so it can be recalled.
• At what age did HM start suffering from epilepsy?


  16
• What surgical procedure did HM undergo at age 27?


  He had surgery to remove his hippocampus from both sides of the brain
• What was the outcome of HM's surgery regarding his epilepsy?


  It cured his epilepsy
• What type of memory was severely damaged after HM's surgery?


  His memory
• How did HM's ability to recall information change after the surgery?


  He could recall information stored prior to the surgery but struggled with new memories
• What personal events did HM struggle to remember after his surgery?


  Death of his mother and father
• How did HM describe his childhood memories after the surgery?


  He loved to describe them but lacked context for when they happened
• What was HM's memory retention duration for new experiences after his surgery?


  He forgot new experiences after 30 seconds
• How did HM interact with psychologists and nurses after his surgery?


  He introduced himself as if they had never met before
• What was HM's short-term memory (STM) capability after the surgery?


  He could hold verbal information for 15 seconds and longer if allowed to rehearse
• What was HM unable to do with the information held in his short-term memory?


  He could not transfer it to long-term memory (LTM) store
• What was HM's ability to access and retrieve information after his surgery?


  He was unable to access and retrieve the information
• What happened to H.M.'s hippocampus to cure his epilepsy?


  It was accidentally removed.
• What was the effect of the hippocampus removal on H.M.'s short-term memory (STM)?


  His STM remained intact.
• How was H.M.'s long-term memory (LTM) affected after the operation?


  His LTM was damaged.
• What type of memories did H.M. love to describe?


  Memories of his childhood experiences.
• What context did H.M. lack regarding his childhood memories?


  He lacked context for how long ago they happened.
• What kind of knowledge did H.M. remember little about?


  Personal events and people in his life.
• What did H.M. know about astronauts?


  He knew what an astronaut was.
• What skill did H.M. learn, despite not remembering being taught it?


  He learned how to play tennis.
• How long did H.M. remember new experiences after his operation?


  He forgot them after 30 seconds.
• How did H.M. behave when he met psychologists after his operation?


  He introduced himself as if they had never met before.
• What was H.M.'s experience with new people he encountered?


  They were like strangers to him.
• What could H.M. not do with new information after his operation?


  He couldn't transfer new information into his long-term memory.
• How does H.M.'s case study support the Multi-Store Model (MSM) of memory?


  • It shows that STM and LTM are separate.
  • It demonstrates that they are independent memory stores.
  • It supports the claim of two distinct memory stores as proposed by the MSM.
• Counterpoint Difficult to generalise the

  findings from an individual case

  to the whole population

  because they are about one

  individual only (unique case), so

  they are specific rather than in

  general.

  Lack of objectivity in the

  researchers as they get to know

  the case or because of

  theoretical bias. This may lead

  to the overlooking of certain

  aspects of the findings

  It would be unethical to try and

  replicate HM's damage, so

  cannot be tested for reliability.
• What is one limitation of the Multi-Store Model (MSM)?


  Evidence of more than one Short-Term Memory (STM) store
• Who studied the client referred to as KF?


  Shallice and Warrington
• What caused KF's brain damage?


  A motorcycle accident
• How was KF's STM affected when digits were read out loud to him?


  His STM for digits was very poor
• What was KF's recall like when he read the digits to himself?


  His recall was much better
• What does KF's case suggest about the components of STM?


  There are separate STM components for visual information and verbal information
• What are the two separate components of STM suggested by KF's case?


  Visual Spatial Sketchpad (VSS) and phonological loop
• Primacy and Recency  It is comprised of the primacy effect... • “The tendency for people to remember the first 5 or so words from the beginning of the list.  And the recency effect... • “The tendency for people to remember the last 5 or so words from the end of the list.
• How does KF's evidence challenge the MSM's claim about STM?


  It suggests that MSM is wrong in claiming there is just one STM store