multi-store memory model

• what are the assumptions of the multi-store memory model?

  • memory is made up of 3 unitary stores
  • memory stores are different individually
  • each store is different and information is transferred from 1 store to another in a fixed, linear sequence
  • each store has a different method of forgetting
• what are 3 main parts of the multi-store memory model?

  • sensory register
  • short term memory
  • long term memory
• what is the capacity of short term memory?

  7 items +/-2
• what is the duration of short term memory?

  18 seconds to 30 seconds
• what is the coding of short term memory?

  acoustic
• what is the capacity of sensory register?

  high
• what is the duration of sensory register?

  less than half a second
• what is the coding of sensory register?

  modal specific
• what is the capacity of long term memory

  unlimited
• what is the duration of long term memory

  unlimited
• what is the coding of long term memory

  semantic
• what is meant by 'decay'?

  the loss of information from memory due to a lack of use or rehearsal over time
• what is meant by 'retrieval failure'?

  the inability to recall information because the relevant cues are not presented
• what is meant by 'maintenance rehearsal'?

  • the process of mentally or verbally repeating information
  • allows the duration of short term memory to be extended beyond 30 seconds
• what is meant by 'displacement'?

  the process in which new information pushes out older information from short term memory due to it's limited capacity (7 +/-2 items)
• what is meant by 'retrieval'?

  the process of accessing information from long term memory and transferring it to short term memory for use
• what is meant by 'prolonged rehearsal'?

  rehearsing information over an extended period, leading it to be transferred from short term memory to long term memory
• give a strength of multi-store model of memory

  • research support demonstrating that STM ad LTM have different characteristics
  • baddeley et al. (1966) found that we tend to mix up words that sound similar when using our STM, supporting the idea that STM coding is acoustic
  • they also found that we mix up words that have similar meanings when we use of LTM, supporting the idea that LTM coding is semantic
  • therefore, this is a strength because it increases the credibility of the MSM as there is evidence backing up a key assumption that STM and LTM are separate stores
• give a weakness of multi-store model of memory

  • contradictory research suggesting that LTM is not a unitary store like the MSM suggests
  • research has found there are 3 types of long term memory
  • semantic (concept-based memories), episodic (event-based memories) and procedural (skill-based memories)
  • therefore, this a weakness because the MSM representation of LTM is too simplistic and this decreases the credibility of the model
• give a weakness of multi-store model of memory

  • contradictory research from case studies suggesting the STM is not unitary like the MSM suggests
  • the case study of patient KF, who has amnesia found his STM for information was very poor when they read out loud to him, but his recall was much better when he was able to read them to himself
  • this suggests there is one STM for visual information and another for verbal information
  • therefore, this is a weakness because the MSM representation of STM is too simplistic and decreases the credibility of the model
• give a weakness of multi-store model of memory

  • alternative explanation of how memory works
  • the working memory model is a representation of how short-term memory is organised and how it functions
  • it states STM consists of 4 main components: the central executive, phonological loop, visuo-spatial sketchpad and episodic buffer which all code differently
  • therefore, this is a weakness as the MSM is not a sole explanation of memory and research behind the working memory model may suggest it is the better model at explaining memory
• give research support for STM duration

  • peterson and peterson
  • participants were shown a consonant trigram and asked to count backwards from a three-digit number to prevent rehearsal
  • after different time intervals (3 to 18 seconds), they were asked to recall the trigram
  • the results showed the the longer the time interval, the less accurate the recall
• give research support for STM capacity

  • jacobs
  • tested digit span by asking participants to recall increasingly long sequences of numbers or letters until they could no longer do so correctly
  • he found the average span was 9.3 digits and 7.3 letters, supporting Miller's (1956) conclusion that STM holds 7 +/- 2 items
• give research support for LTM duration

  • bahrick et al.
  • tested 392 American ex-students aged 17-74 on their memory of former classmates using free recall and photo recognition tasks based on high school yearbooks
  • they found photo recognition accuracy was about 90% after 15 years and 70% after 48 years, while free-recall dropped from 60% to 30% over the same period, showing that long term memory can last for decades
• give research support for coding of LTM and STM being different

  • baddeley
  • gave participants lists of acoustically or semantically similar or dissimilar words to recall either immediately (testing STM) or after 20 minutes (testing LTM)
  • participants struggled with acoustically similar words in STM and semantically similar words in LTM, indicating the STM is coded by sound and LTM by meaning
• evaluation of peterson and peterson research

  • weakness - ecological validity (trigrams)
  • strength - high control over extraneous variables (cause and effect can be established)
• evaluation of jacobs research

  • weakness - 1887, outdated, low control
  • strength - research support from Miller
• evaluation of bahrick et al. research

  • weakness - confounding variables (e.g looking back to refresh memory)
  • strength - high ecological validity (task of remembering old photos is common)
• evaluation of baddeley research

  • weakness - low mundane realism (artificial stimuli)
  • strength - high control over extraneous variables (cause and effect can be established)