The multi-store model of memory

Who created the multi store model?

Atkinson and Shiffrin

What is the multi store model?

A representation of how memory works in terms of three unitary stores called the sensory register, STM and LTM.

It also describes how information is transferred in a linear way from one store to another and what makes some memories last and disappear.

What is the sensory register?

Takes info from the environment via one of the sense organs and holds it in that same form in a store. There is a store for each of the 5 senses.

What is the coding of the sensory register?

Depends on the way info enters.

Iconic memory (visual info is coded visually)

Echoic memory (auditory info is coded acoustically)

Haptic memory (touch/tactile memories)

What is the capacity of the sensory register?

HIGH

e.g. 100 million cells in each eye, which store data

What is the duration of the sensory register?

Less than half a second

What is the key process of the sensory register?

Attention

If we pay attention, the info passes onto the STM

What is the coding of short term memory?

Info is coded acoustically

What is the capacity of short term memory?

Has a limited capacity store of 5-9 chunks

What is the duration of short term memory?

Lasts less than 30 seconds (18-30) unless rehearsed.

What is the key process of short term memory?

Maintenance rehearsal

When we rehearse material to ourselves over and over again it will remain in our STM.

If we rehearse it for long enough (prolonged rehearsal) the info passes from STM into LTM.

Forgetting occurs when info can decay in STM due to lack of maintenance rehearsal.

What is the LTM?

Where info is stored if it is properly rehearsed in the STM.

Potentially permanent memory store.

What is the coding of LTM?

Semantic

What is the capacity of LTM?

Unlimited

What is the duration of LTM?

Potentially up to a lifetime

e.g. Bahrick et al found that many participants were able to recognise their classmates almost 50 years after graduating

What is the key process of the LTM?

Retrieval

Info can be recalled back from the LTM to use in STM.

What is a strength of the MSM?

Support from studies showing that STM and LTM are different.

E.g. Baddeley found that we tend to mix up words that sound similar when we are using our STMs. But we mix up words that have similar meanings when we use our LTMs.

This shows that the STM and LTM are separate and independent memory stores, as claimed by the MSM.

What is a limitation of the MSM? (Lacks validity)

Lacks validity

In everyday life, we form memories related to things such as faces, names, places etc.

But studies that support the MSM used none of these materials. Instead they used digits, letters (Jacobs) or consonant syllables (Peterson and Peterson) that have no meaning.

This means that the MSM may not be a valid model of how memory works in our everyday lives where we have to remember more meaningful info.

What is another limitation of the MSM? (Shallice and Warrington)

Evidence of more than one STM store

Shallice and Warrington studied a client known as KF who had amnesia. KF’s STM for digits was very poor when they were read out loud to him. But his recall was much better when he read out digits to himself.

Further studies of KF showed that there could be another STM store for non-verbal sounds e.g. noises.

This suggests that the MSM is wrong in claiming that there is just one STM store processing different types of info.

What is another limitation of the MSM? (Craik and Watkins)

Prolonged rehearsal is not needed to transfer to LTM

According to the MSM, the amount of rehearsal is what matters to transfer it to LTM.

But, Craik and Watkins found that the type of rehearsal is more important than amount. Elaborative rehearsal is needed for long-term storage. This occurs when you link the info to your existing knowledge. This means that the info can be transferred to the LTM without prolonged rehearsal.

This suggests that the MSM does not fully explain how long term storage is achieved.

What is another limitation of the MSM? (Atkinson and Shiffrin)

Research shows that STM and LTM are NOT single memory stores.

MSM states that the STM and LTM are single memory stores, separate and independent from each other.

But Atkinson and Shiffrin suggest that it is not. E.g. we have one LTM store for our memories of facts about the world and a different one on how to ride a bicycle.

This shows that the MSM is an oversimplified model of memory.