features of each store for the MSM

• who conducted research for the coding and capacity of the STM

  miller (1956)
• what observation did miller identify

  miller made observations of everyday practice. for example he noted that things come in 7s such as the 7 deadly sins, 7 notes on a musical scale and 7 days a week
• what did millers findings show

  that the span STM is approximately 7 items (plus or minus 2) but this can be improved by chunking (group sets of digits/ letters into meaningful units)
• what is the capacity of the STM

  5-9 items
• who conducted a study on the duration of the STM

  Murdock
• what did Murdock do

  • gave ps a list of 20 words in a certain order
  • asked them to revise the list and then recall them
  • found that the ps could recall the being of the list well as they and rehearsed it and stored it in the LTM
  • words in the middle of the list are often forgotten as they are in neither stores
  • the words at the end of the list are recalled better then those in the middle as they likely to have been the last 5-9 items read in the last 18-30 seconds
• what does murdocks study show about the duration of the STM

  the recency effect shows that words could be recalled if heard in the last 18-30 seconds
• who conducted research for the coding on the LTM

  Baddeley (1966)
• what did Baddeley do

  • p were given a list of words to learn
  • group 1 - acoustically similar words such as cat, cab and can
  • group 2 - acoustically dissimilar words such as pit, few and cow
  • group 3 - semantically similar words such as great, large and big
  • group 4 - semantically disimilar words such as good huge and hot
  • ps asked to recall straight away (STM) did worse on acoustically similar words
  • ps who were asked to recall after 20 mins (LTM) did worse on semantically similar words
• what is the conclusion of Baddeleys study

  the words on the LTM must be coded semantically as when recalling words that mean the same is causing confusion and are not recalled well
• who conducted a study one the duration

  Bahrick et al
• what did Bahrick et al do

  • ps were 392 Americans aged between 17 and 74

  1. recognition test - 50 photos from ps high school year book
  2. free recall test - ps listed names of their graduating class

  • ps tested 48 years after graduation were about 70% accurate in photo recognition
  • free recall was much less accurate - high ecological validity
• what is the duration of the LTM

  the duration of the LTM is perminate which is shown by the ps being able to recall names after a long period of time
• what is a limitation of studies (PEEL) (overestimated)

  P - a limitation of Miller's research is that it may have overestimated capacity of STM

  E - other researchers have suggested that millers estimate of STM holding 5-9 items is too high

  E - for example, other researcher have suggested that the capacity is approximately 4-5 chunks

  L - this suggests the lower end of millers estimate (5 items) is a more appropriate number for the capacity of STM
• what is a limitation of studies (PEEL) (artificial stimulus)

  P - another limitation is that the murdock study uses artificial stimulus

  E - the task requited ps learning and recalling lists of words in a specific order which is not a very meaningful task

  E - this way of assessing memory is not reflective of how memory in real life. For example, in real life we use our memory for travel, school, home, address

  L - this suggest that murdock study are not very applicable to how we use our memory in real life and has low ecological validity and questions whether we should take this research as useful to understanding memory
• what is a strength of studies (PEEL) (high external validity)

  P - a strength of Bahrick et al's study is that is has high external validity (real life application)

  E - Bahrick's study uses real life memories of personal meaningful memories if people they went to school with and therefore are not artificial

  E - when lab studies were done where meaningless pictures jad to be remembered, the recall rates were much lower

  L - however, the downside pf real life research is that confounding variables are not controlled. For example Bahrick's ps may have looked at their yearbook photo's and rehearsed their memories over the years