Multi-Store Model Flashcards
What is the coding, capacity and duration of the Sensory Register
Coding- iconic/echoic
Capacity- 9-18 items
Duration- Approximately 250ms
What is the coding, capacity and duration of the Short Term Memory
Coding- Acoustic
Capacity- 5-9 items
Duration- 18-30 seconds
What is the coding, capacity and duration of the Long Term Memory
Coding- Semantic
Capacity- Unlimited
Duration- Forever
Sperling Experiment- Capacity of Sensory Register
Condition 1
- Flashes a 3x4 grid of letters on the screen for 250ms.
- Participants were asked to recall any letters.
- Results= 3-4 letters recalled.
Condition 2
- Flashed grid for 250ms.
- Low, medium or high tones played after.
- Asked to recall row for that tone.
- Results= 3/4 from the tone row. So remembered 9-12 letters in total.
Jacobs Experiment- Capacity of STM
- Gave participants letters, numbers of words and increased them by one each time. Asked them after each increase to immediately recall strings of letters/numbers.
- Found that people could generally recall between 5-9 items. Chunking letters could increase capacity.
Peterson Experiment- Duration of STM
- 3 nonsense letter trigrams were showed.
- They had to count back in 3s from 300, so no maintenance rehearsal.
- The counting increased in 3 second intervals.
- They found that 90% of trigrams were remembered after 3 seconds, 5% after 18 seconds.
- Duration STM= 18-30 seconds.
Baddley Experiment- Encoding of STM and LTM
- 4 Conditions- Acoustically similar and dissimilar, Semantically similar and dissimilar.
- They were all recalled immediately and after 30 minutes.
Results - Acoustically similar sounding words were confused on immediate recall. STM= acoustic encoding.
- Semantically similar words were confused after 30 min recall. LTM= semantic encoding.
Bahrick Experiment- Duration of LTM
- 50 photos shown from school yearbook.
- Asked to match name to photo or free recall.
Results
Up to 15 years - 90% accuracy matching
- 60% on free recall
After 48 years - 60% recall matching
- 30% free recall.
Evaluation- Limitation of MSM
One limitation is that the MSM has been criticised for it’s over emphasis on the need for maintenance rehearsal to get information into LTM. Craik and Lockhart suggested that long term memories can be formed by elaborate rehearsal. They argued that through processing information semantically we are more likely to remember it in our LTM. This is a limitation because in real life, not all events need to be repeated through maintenance rehearsal. This is processed more deeply through elaborative rehearsal and the emotional and semantic context of the information is integrated into the memory, therefore MSM is not an effective model to explain human memory. Despite this, there is evidence for the need for maintenance rehearsal when information is processed structurally. This creates a much shallower form of processing, therefore maintenance rehearsal is sufficient to create a long term memory.
Evaluation- Criticism of MSM
A further criticism of the MSM is that it’s view on STM is too oversimplified. The MSM states that in STM, information is coded acoustically and in LTM, information is coded semantically. This is a problem because it fails to consider other types of processing that may be occurring in each store. Therefore, how our memory actually works may be more complex. The MSM should be considered as reductionist, and an incomplete explanation of human memory. In contrast the WMM believes that STM is made up of different stores that have a different role in processing memory. Therefore, this model considers multiple types of coding and gives a more detailed view of the STM, which can be seen as more valid than the MSM.
Evaluation- Strength of MSM
One strength of the MSM is it proves there is a distinction between the STM and LTM. HM had a brain damage that was caused by an operation that removed his hippocampus, so LTM didn’t work. He was able to remember information for up to 15minutes with constant maintenance rehearsal. This shows that STM and LTM are two different stores because if they were one store HM wouldn’t be able to use either. Therefore, this suggests that MSM is valid. However, HM was a unique individual with unique brain damage. So in typical population, the STM and LTM may not be separate. This means conclusions made about the MSM can’t be generalised to the typical population.
