The multi-store model of memory

The multi-store model of memory

1. Sensory memory

   • Short duration store retaining unprocessed impressions of information. Separate sensory store: Iconic store- visual information Echoic store: auditory inforamtion.Trace decay results in information being lost rapidly from SM, through paid attention to passes to STM for lasting representation.
   • Research studies: Crowder(2003) found that SM retains info for a few milliseconds within iconic store but about 2-3 seconds within the echoic store, suporting the idea of a seperate sensory store for each sensory input.

2. Short term memory

   • . Active memory system containging infromation currently being through about.Temporary storage of information from the SM
   • Encoding
     • Acoustic
     • Baddeley: 75 participants were presented with 1 of 4 lists repeated 4 times. (acoustically similar etc). Participants given list A (Acoustically sim.) performed the worst, recall:10%. Recall for others- good between 60% and 80%.
       • Acoustic confusion in STM suggesting STM is encoded on an acoustic basis
   • Capacity
     • 7+-2 items
     • Jacobs (1887) gave particicpants increasingly longer lists of either letters or numbers, finding capacity for numbers was nine items and for letters was seven items
       • numbers may be easier to recall as there are only nine of them, compared to 26 letters in the English language
   • Duration
     • 18-30 seconds
     • Peterson and Peterson (1959) read nonsense trigrams (ASX) to participants and got them to count backwards in 3's from a large 3 digit number for 3-18 seconds to prevent rehearsal. 90% trigrams recalled after 3 seconds but only 5% at 18 seconds
       • STM duration: 20-30 seconds
       • Recalling nonsense trigrams has nothing to do with STM tasks occuring in our everyday lived and therefore lacks mundane realism

3. Long term memory

   • Storage of information over extended periods of time. Storage oflonger than 30 seconds counts as LTM.
   • Encoding
     • Semantic
     • Baddeley (1966) used the same procedure as STM but with 20 minute interval. Before recall participants conducted another task. Participants who had list C (semantically similar) had only 55% recall however recall for the other lists were 70-85%.
       • Semantic encoding makes cognitive sense
   • Capacity
     • unlimted
     • Anokhin (1973) estimated that the number of possible neuronal connections in the human brain is 1 followed by 10.5 million kilometres of noughts. He concluded "no human yet exists who can use all their brain", suggesting that the capacity of LTM is limitless.
     • Assumed to be limitless as research has not been able to determine a finite capacity
   • Duration
     • Up to to a lifetime
     • Bahrick (1975) showed 400 participants aged 17-74 years a set of photos and a list of names, some were old school friends and asked to indentify old friends. Those who had left school within 15 years recalled 90% of faces and names. Those who left 48 years ago recalled 80% names and 70% faces.
       • Memory for faces are long lasting
     • Difficult to ascertain whether information is actually lost from LTM; it may be more difficult to access

4. Evaluation

   • Positive
     • The MSM was influential and paving the way for subsequent models- greater understanding of how memory works
   • Negative
     • MSM describes memory in terms of structure, namely the three memory stores and the processes of attention and verbal rehearsal. However, MSM focuses too much on structure and not enough on processes
     • Too simple