Compare the differences between any two models of memory.

Research has been conducted that supports what Atkinson and Shiffrin proposed regarding the differences in each “store’s” capacity, duration and the type of encoding carried out. The separate memory theory is also backed by brain scans, which show different parts of the brain “working” when the person is carrying out different tasks, e.g. if someone was carrying out a task in the STM (running through a long strand of random numbers), the scan would show that the Pre-frontal cortex was more active whilst if a task was being carried out that required the LTM (recalling a birthday of someone special) the scan would show the Hippocampus was more active. A study carried out by Milner (1966) furthered supports Atkinson’s and Shiffrin’s theory that there are separate memories even in the physical world, for Milner was studying a man whom he called H. M. who had to have both his Hippocampi removed due to a tumour. This appeared to mean he could no longer form long term memories but was still capable of performing a STM task.ff

Support for the Working memory model is easy to find e.g. Baddeley and Hitch (1976), they gave the participants two tasks to carry out simultaneously, Task 1 was to say true or false to statements (the experiment can be seen on page 15 of the Cardwell, Clark, Meldrum book), the second possible task was to say a random string of digits (this used the articulatory loop and the central executive and the last possible task was to do nothing else at all. The speed of task 1 only varied when the central executive was in use, remaining the same when either only the articulatory loop used or when no other task was carried out. This shows that when using the same component for two different tasks difficulties arise but when different components are used, performance is not affected. Other support for Baddeley and Hitch was given by Tronjano and Grossi (1995) (subject called SC) and Farah et al. (1988) (subject called LH) when they carried out studies on people with brain damage and found that their respective patients had damage to the phonological loop and was unable to remember word pairs that were said aloud and that the other had difficulty on visual tasks but not on spatial tasks suggesting that the Visuo-spatial sketchpad was in fact two “pads”.

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Even with all the evidence to support the MS model, it is still a too oversimplified and reductionist theory of the memory process. This can be backed by the Multi-store model only proposing one long term store whilst, vast amounts of research suggest that there are many different stores (e.g. semantic, implicit and explicit). It also only proposes one short term store whilst Baddeley and Hitch, who put forward the Working memory model, show in one of their tests, that there are at least two stores, the Visuo-spatial sketchpad and the Phonological-loop. Baddeley and Hitch also provide much more detailed descriptions and explanations about the STM than those of Atkinson and Shiffrin, but they failed to give any theory on the LTM, which though a fairly minor failing, it does mean that you cannot easily predict how any, if they any of the units in the Working memory model do, interact with the LTM and how information is recalled and remembered. ff