The Multi store model of memory

The Multi store model of memory

1. It is an explanation of how memory processes work

2. 3 main components

   • Sensory memory
     • Composed of several stores- eyes,ears,nose,fingers etc and the corresponding areas of the brain
     • Constantly receiving info, most receives no attention and remains in sensory store for very brief period
     • If attention is focused on one of the sensory stores, transferred to STM
   • Short term memory
     • Information will 'decay' disappear quickly if not rehearsed
     • It will also disappear if new info enters the STM pushing out(displacing) the original information
       • STM has limited capacity
     • 7+-2 capacity
   • Long term memory
     • The more something is rehearsed the more lasting the memory will be
       • Maintenance rehearsal- largely verbal
     • Unlimited capacity

3. Atkinson and Shiffrin (1968)

4. Evidence for 3 separate stores

   • The sensory store
     • Sperling (1960)
     • Participants saw grid of letters+digits for 50 milliseconds, either asked to write down all 12 or told they would hear a tone immediately after and should write down that row
       • When asked to write down whole thing recall was poorer. (5 items recalled=42%) When asked to give one row (3 items recalled=75%)
         • Shows info decays rapidly in sensory store
   • The serial position effect
     • Glanzer&Cunitz (1966)
     • Gave participants 20 words presented one at a time and then asked to recall them
       • Tended to remember words from start of the list (primacy effect) and from the end of the list (recency effect) less good at recalling words in middle
         • Primacy effect occurs, first words are best rehearsed and transferred to LTM. Recency effect occurs because words are in STM when asked to recall the list
   • Areas of the brain associated with STM and LTM
     • Link STM and LTM to specific areas of the brain. Modern techniques of scanning the brain can be used (PET scans and fMRI- used to detect brain tumours)- they take images of active brain and enable us to see what region is active when a person is doing a particular task
     • Research found prefrontal cortex active when individuals working on STM task (Beardsly,1997). Whereas hippocampus is active when LTM is engaged (Squire et al, 1992)

5. Evaluation

   • Strengths
     • Strong evidence of 3 different stores
     • Model does provide an account of memory in terms of both structure+process
     • Clear predictions about memory meaning psychologists can conduct studies to test it.
   • Limitations
     • Oversimplifies memory structures memory structures and processes
     • STM and LTM are not completely separate stores
     • Rehearsal is not the only way to transfer from STM to LTM: processing can also do it (semantics)

6. Structures: STM+LTM are not unitary stores

   • Evidence for non-unitary STM came from case study of KF- suffered brain damage resulted in difficulty dealing with verbal info but normal ability to process visual suggesting STM has more than one store
   • LTM has more than one store suggested by people with amnesia. Spiers et al (2000) studied memory in 147 patients with amnesia.

7. How separate are STM+LTM?

   • Logie (1999) pointed out STM relies on LTM therefore cannot come 'first' as suggested