Multi-Store Model of Memory (MSM)

• Atkinson and Shriffin - 3 different but interconnected memory stores. Sensory Information Store (SIS) - Short Term Memory (STM) - Long Term Memory (LTM)
• SIS - All Information recieved by the brain. Information is lost through decay if not paid attention to.
• STM - Rehearsal needed to keep information stored in STM. Capacity = 5-9 items. Duration = 30 seconds. Information is stored in the STM acoustically (said out loud). Information is lost through decay and displacement. 
• LTM - Rehearsal is needed for information to be moved from STM to LTM. Capacity = unlimited. Duration = Up to a lifetime. Information is stored semantically (by meaning). 
  KEY TERMS. 
• Encoding - Information to be remembered has to be converted into a different form for each store. EG acoustic/semantic. 
• Capacity - How much storage space each store has.
• Duration - How long information lasts in each store. 
• Control Processes - Passages of information between each store 
• Attention - For information to enter our sensory store, we must pay attention to it. 
• Rehearsal - For information to remain in our STM we repeat it (maintenance rehearsal). To keep information in our LTM we use Elaborative Rehearsal. 

Outline the Multi-Store Model of Memory (6 marks)

How was the research conducted?
Digit Span Technique - requires participants to hear/read a set of random digits and repeat them in the same order (Serial Recall).  List of digits start at 4 and get longer each time until the participant can no longer recall them correctly. At this point, it represents the capacity of their STM.

What did the research show?
Jacobs - suggested the capacity of STM is limited to 5-9 items.  When new information is received by the STM, it pushes out old information (Displacement).  
He concluded that STM has limited capacity and that when our STM reaches this limit, new information displaces the old information.

Miller (Similar Research) - found the "Magic Number 7".  Generally people can hold 7 + or - 2 pieces of information.  Miller claimed the rule applies to words aswell as numbers.  Also argued that our STM can be increased through "chunking" meaning if we chunk information into meaningful groups we can hold more information into our STM