Multi store model

• What is memory?

  The ability to store and retrieve information.
• Clive Wearing lost his ability to store information in his long term

  memory
• Anterograde amnesia


  A condition that doesn't allow new

  memories to transfer from short term memory into long-term memory
• Due to a virus that attacked his ‘hippocampus’, Clive Wearing has

  Anterograde Amnesia
• Clive will never remember anything new since being ill
• Clive can still play piano flawlessly but and can only remember his wife
• The multi store model of memory was founded by...


  Atkinson and Shiffrin (1968)
• What 3 stores did Atkinson and Shiffrin identify in memory?

  Sensory register, short-term memory, long-term memory
• Whats the capacity of sensory register?

  very large
• research for SR capacity?

  For visual information

  Showed participants a grid of 12 letters for 1/20 of a second

  Found that on average the participants could only remember 4.32 letters (approx 1/3 of grid)
• research for SR capacity: 2nd condition

  Sperling

  showed his participants another grid of letters, but as

  soon as they had seen it he played either a high pitched

  tone, middle pitched or low pitched tone, to indicate

  whether they had to recall the top, middle or bottom row.

  Sperling found that participants recalled on average 3.04

  out of the 4 in the row

  This suggests that most of the grid was available in the

  sensory register (approximately ¾ of the grid, or 9 letters)

  This supports the concept of the sensory register and

  shows that the capacity of the sensory register is very

  large
• SR coding?

  Modality specific
• What is meant by modality specific?

  information is stored in the same format as it

  was received, as a literal copy
• There is a sensory register for each sensory system:

  • Iconic store- visual 👀

  • Echoic store- auditory 👂

  • Haptic store- tactile

  • Gustatory store- taste 👅

  • Olfactory store- smell 👃
• SR duration?

  1/2 - 2 seconds
• Echoic (auditory) memory is thought to last longer – approx 2 seconds.

  • This was shown by Treisman (1964) who presented identical auditory

  messages to both ears of participants, with a slight delay between them.

  Participants could only identify that the messages were the same if there

  was less than a 2 second delay between them
• How does information transfer from SR to STM?

  Attention

  When we focus our attention on a piece of information in

  our sensory register it gets passed to STM and we become

  aware of it
• What is meant by short term memory?

  the information that you are currently aware

  of, the information you have in your mind now
• STM capacity?

  7+/-2
• Research for STM capacity

  Miller (1956)- digit span test

  One person (experimenter) will receive a list of digits

  Partner doesnt know list of digits.

  The number of digits increases by one, every

  third row.

  The experimenter reads out each row of numbers to the

  participant, one row at a time and partner should try to repeat back each row

  Continue all the way down the rows, putting a tick or cross next to each row on list if partner correctly/incorrectly recalls them all in order.

  See to what length list they get before they can’t remember/mistakes are made.
• STM coding?

  Acoustic
• Research for STM coding

  Baddeley (1966)

  He found that participants had difficulty remembering words that are acoustically similar.
• STM duration

  15-30 seconds
• Research for STM duration

  Peterson and Peterson (1959)

  read nonsense trigrams (a set of 3 nonsense consonants) to participants, and then got them to count backwards in threes for varying periods of time (to prevent rehearsal), before they had to recall them. The time periods were 3,6,9,12,15 and 18 seconds.

  The longer the delay (without rehearsal) the worst the memory.
• How does information transfer from the STM to LTM?

  Rehearsal
• LTM capacity?

  Unlimited
• Research for LTM capacity

  Wagenaar (1986): during a period of 6 years he kept a

  daily record of one or two events of his own day-to-day

  life. He recorded over 2400 events and reported good

  recall, concluding that many items can be stored in LTM,

  supporting the idea that the capacity of LTM is extremely

  large or ‘unlimited’.
• LTM duration?

  Many years
• Research for LTM duration

  Bahrick et al (1975)

  showed participants aged between 17 and 74 yrs a set of pictures of people with their names, some of which were people they had gone to school with.

  • Those who had left school 48yrs previously could correctly identify 80% of names of those they had gone to school with, and 70% of faces.

  • Showing the duration of LTM can be many years.
• LTM coding?

  semantic
• Research for LTM coding?

  Baddeley (1966)

  found that words that are semantically similar are more likely to be confused in LTM (similar to the confusion of acoustically similar words in STM).

  • This shows that LTM uses a semantic code for words.

  Baddeley (1966)
• Research for LTM coding

  Baddeley (1966)

  participants were given the original words in the wrong order. Their task was to rearrange the words in the

  correct order.

  there was a 20 minute interval between learning and recall. During

  which participants performed another task to prevent rehearsal.

  participants with semantically similar words (C)

  performed the worst with a recall of only 55%. They confused

  similar meaning words e.g. recalling large instead of huge. Recall of the other lists was comparatively good at between 70-85%

  support for STM using acoustic and LTM using semantic