M: Lesson 4: Evaluation of the Multi Store Model of memory

Question 1

What are the positive Neurobiological evidence supporting the MSM?

Answer 1

• Scoville attempted to treat HM’s epilepsy by removing several brain areas, including his hippocampus where LTM is stored. This resulted in HM being unable to code new long term memories, while his short term memory is unaffected. This supports the idea of separate LTM and STM.
  Shallice and Warrington reported the case of KF who was in a motorcycle accident, and had reduced STM capacity of only one or two digits, but his LTM was unaffected. This supports the idea of separate LTM and STM. However, KF had poor STM for verbal tasks, not visual tasks and this suggests there is different types of STM, unlike the multi store model of memory suggests. In addition, according to MSM, LTM are retrieved by STM, so if ST, is damaged, it should be difficult to retrieve LTM. However, KF was able to access LTM without any difficulty.

Question 2

What are the positive lab experiments supporting the MSM?

Answer 2

Murdock presented participants with a long list of words to be recalled in any order, this was referred to as the free recall experiment. Words at the beginning and the end of the lists were recalled better than those in the middle. This is called serial position effect. Words at the beginning of the list are recalled because they have been constantly rehearsed and transferred to LTM (the primacy effect) while words at the end of the list are recalled because they are still in STM (the recency effect). This supports the idea of separate STM and LTM.

Question 3

What are the positive lab experiments supporting the MSM?

Answer 3

Murdock presented participants with a long list of words to be recalled in any order, this was referred to as the free recall experiment. Words at the beginning and the end of the lists were recalled better than those in the middle. This is called serial position effect. Words at the beginning of the list are recalled because they have been constantly rehearsed and transferred to LTM (the primacy effect) while words at the end of the list are recalled because they are still in STM (the recency effect). This supports the idea of separate STM and LTM.

Question 4

What are the negatives of MSM?

Answer 4

• The MSM is over simplified in assuming that there is only one type of STM and one type of LTM. Research studies indicate that there are several types of STM, such as one for verbal information (phonological loop) and another for non-verbal information (visuo-spatial sketchpad). Research also suggests that there are several types of LTM (episodic, semantic, procedural).
• Baddeley and Hitch claimed the MSM could not explain the ability to multi task, if there is only one type of STM, then multitasking would not be possible. However, people multitask all the time.