The multi-store model of memory

• The multi-store model is an explanation of memory proposed by Atkinson and Shiffrin which assumes there are three unitary (separate) memory stores, and that information is transferred between these stores in a linear sequence.
• According to the MSM only sensory information that is paid attention to is passed from the SR and is encoded into the STM, while the rest is lost through decay.
• According to the MSM, maintenance rehearsal must occur to maintain information in our STM.
• According to the MSM, elaborative rehearsal must occur for information to be passed from the STM and encoded into the LTM.
• According to the MSM, for information to be recalled from the LTM, it must be transferred back to the STM by retrieval.
• A strength of the MSM is that brain scanning techniques has supported the Multi-Store Memory model and the idea of separate memory stores. Squire et al (1992) used brain-scanning techniques and found that STM can be associated with activity in the prefrontal cortex and that LTM can be associated with activity in the hippocampus. This is a strength because it provides biological evidence that the different memory types are processed in different parts of the brain and that the memory stores are seperate as the multi-store model suggests.
• A strength of the MSM is that case studies of brain damaged patients (e.g. KF) have also offered support for the Multi-Store Model of memory. Shallice and Warrington (1970), reported the case of KF, who was brain damaged as a result of a motorcycle accident. His STM was severely impaired, however his LTM remained intact. This supports the view that STM and LTM are separate and distinct stores and therefore supports the proposals of the Multi-Store Model of memory as it shows that it is possible to damage only one store in memory, while the rest is left intact.
• A weakness of the MSM is that it is too simplistic as it ignores the sub-stores of LTM and instead, labels it as a unitary store which has been disproven by the HM case. HM had his hippocampus removed by Dr Skoville in an effort to better his epilepsy. HM could no longer create new LT memories, but his procedural memory was intact allowing him to gradually get better at the tracing a star by looking in the mirror. However, HM would forget he ever attempted the task, showing a loss of declarative memory. This limits the MSM as it shows there are different LTM.
• A strength of the MSM is the HM study. Dr Skoville removed a part of HM's hippocampus in hopes to reduce the seizures HM was experiencing, but his memory worsened as HM could no longer form new LT memories while his STM stayed intact. This shows that LTM and STM are separate stores as said in the MSM as he could remember a set of numbers for 15 minutes using rehearsal, but couldn't transfer this into his LTM as the hippocampus, which is involved in memory consolidation, was removed. Therefore, the HM study shows evidence for the MSM as it proves that LTM and STM are separate memory stores.
• A weakness of the MSM is that most of the research supporting the MSM use artificial stimuli. Meaningless stimuli are less likely to be remembered than useful material we come across in our everyday life. This means that the MSM may not be accurate or valid model of how memory works in our everyday life, where we have to remember meaningful information.
• Neuroimaging evidence suggests that different types of memory are stored in different parts of the brain.
• Atkinson and Shiffrin’s Multi-store model of memory includes three unitary stores which include: sensory register, short term memory and long term memory.