Multi-Store model

• The Multistore Model

  Atkinson and Shiffrin’s MSM describes how information flows through the memory system. The model suggests that memery is made up of three stores and is linked by processing.
• Stimuli from the environment reaches the sensory register. This is spilt up into the Iconic, Echoic and other sensory stores. Attention to these stimuli make them short term memories. Prolonged rehearsal of maintenance rehearsal leads to them being in the long term memory store. Memories from LTM transfer to STM for retrieval.

  
• Sensory register

  All stimuli from the environment pass into the sensory register. This part of memory comprises several stores, one for each of our 5 senses. Coding in each store is modality specific -depends on the sense. The store coding for visual is iconic memory & the store coding for acoustic is echoic memory. There are other sensory stores for other information.
• Sensory Register Duration

  Duration of material in SR is very brief - less than half a second. The SR has a very high capacity - over 100 million cells in each eye, each storing data. Information passes further into the memory system only if you pay attention to it: key process.
• Short Term Memory

  Information in STM is coded acoustically and lasts about 18 seconds, unless it’s rehearsed so STM is more of a temporary store. STM is a limited capacity store; it can only hold a certain number of items before forgetting occurs. Capacity is about 7+-2 according to Miller and 4+-1 according to Cowan. Maintenance rehearsal occurs when we repeat material to ourselves over and over again. We can keep the information in our STM as long as we rehearse it. If we rehearse it long enough it passes into our LTM.
• Long term memory

  This is the potentially permanent memory store for information that has been rehearsed for a prolonged time. LTM is coded semantically. Psychologists believe that its duration may last up to a lifetime. Bahrick found that many of the participants were able to recognise the names and faces of their school classmates almost 50 years after graduating. The capacity of LTM is thought to be unlimited.

  According to the MSM when we want to recall something from LTM, it has to be transferred back into STM by a process called retrieval.
• +There is evidence of more than one STM store. Shallice and Warrington studied a client referred to as KF who had a clinical memory disorder: amnesia. KT’s STM for digits was very poor when they were read out loud to him. His recall was much better when he read the digita to himself. Further studies of KF (and others) showed that there could be another STM store for non-verbal sounds: noises. This evidence suggests that the MSM is wrong in claiming that there is just one STM store processing different types of information.
• -Prolonged rehearsal isn't needed for transfer to LTM. According to the MSM the amount of rehearsal is key. Craik and Watkins found that the type of rehearsal is more important than the amount. Elaborative rehearsal is needed for long-term storage. This occurs when you link the information to your existing knowledge, or you think about what it means. This means that information con be transferred to LTM without prolonged rehearsal and that the doesn't fully explain how long term storage is achieved.
• +Studies show STM & LTM are different. Baddeley found that we tended to mix up words that sound similar when using our STM. But we mix up words that have similar meanings when we use our LTM. Further support comes from studies of capacity and duration. These studies clearly show that STM and LTM are separate and independent memory stores, as claimed by the SMS.
• -However, many of the studies that support differences of STM and LTM don’t use materials such as people's faces, names, facts, places etc. This means that the MSM may not be a valid model of how our memory works in everyday situations where we have to remember much more meaningful information.