2. Memory Flashcards
Who created the MSM?
Atkinson and Shiffrin - 1968
MSM
A memory model that sees information flowing through a series of sstorage systems
Draw MSM
AO1
Explain MSM (AO1)
- Begins with sensory register
- SR has a capacity that is large, a duration between 0.5-2s and the coding depends on the sense that is picked up, (each sense has a sub-store, Ex: Echoic store detects auditory information)
- If this information is important we pay attention to it, which transfers it to the STM - If we don’t pay attention to it, then the information decays
- STM has a capacity of 7±2 , (Miller’s magic number), a duration of 18-30s and is coded acoustically
- If this information is important, then we rehearse it, which transfers it to our LTM
- LTM has an unlimited capacity, a duration that lasts a lifetime and the information is coded semantically
- It is also important to note this model sees STM and LTM as being unitary stores
Evaluate MSM (AO3)
- Supported by neuroimaging studies by Beardsley and Squire - These studies show that when the STM is being used, our pre-frontal cortex is active and when our LTM is being used the Hippocampus is active - This shows STM and LTM take place at different parts of the brain
- Patient HM
- Patient KF
- The model is criticised for being over-simplified, (for instance, there are three types of LTM but it is shown as a unitary store) –> Compare to WMM
- Most of the studies that support MSM lack ecological validity and mundane realism as the Brown-Peaterson technique which was commonly used is unrealistic to taks people have to carry out in day to day life
KF Case Study
- Patient KF was in a motorcycle accident and entered a coma
- Doctors believed he would suffer from brain damage
- Doctors predicted he would be unable to form new STM, but according to the model which says information is passed logically and sequentially, this also means he wouldn’t be able to form LTM
- When he woke up, doctors ran tests which showed his STM was impaired, however, his LTM wasn’t impaired
- Patient KF also tested better on visual short-term memory tasks than verbal tasks, supporting the existance of multiple STM stores, which proves MSM may be oversimplified
HM Case Study
- Patient HM had epilepsy and in order to treat it, doctors had to surgically remove his hippocampus
- After surgery, they found HM was able to form new STM but not new LTM, which supports the neuroimaging studies of Beardsley and Squire, as it shows that the STM and LTM formation/usage takes place at different parts of the brain
Brown-Peaterson technique
- Presents a triagram to Ps
- Ps are then asked to count backwards by a given number, to prevent rehearsal
- They are then given a signal to recall the triagram
Tests short-term recall, without the use of rehearsal
Aim: Baddeley
AO1
To assess whether coding in the STM and LTM is mainly acoustic or semantic
Procedure: Baddeley
AO1
- 75 Ps were presented with one of four word lists
- These word lists were repeated four times
- List A = Acoustically similar words - Ex: Cat, Mat and Sat
- List B = Acoustically disimilar words - Ex: Pit, Day and Cow
- List C = Semantically similar words - Ex: Big, Tall and Huge
- List D = Semantically disimilar words - Ex: Hot, Safe and Foul
- To test coding in STM participants were given a list of words in the worng order and were asked to rearrange them into the right order
- To test coding in LTM participants had to do the same procedure, however, they had to do a 20-minute interference task before recall, (this prevented rehearsal)
Results: Baddeley
AO1
- For STM participants given List A performed the worst with a recall of only 10%
- For LTM participants given List C performed the worst with a recall of only 55%
Conclusion: Baddeley
AO1
- Since List A was recalled least accurately, it means that there was acoustic confusion, suggesting that our STM is coded acoustically
- Since List C was recalled least accurately, it means that there was semantic confusion, suggesting that our LTM is coded semantically
Evaluation: Baddeley
AO3
G: Baddeley had a good sample size, meaning that anomalies, (ex: People with a really good or bad memory), will be averaged out, meaning the results are generalisable - However, because there were lots of conditions, there weren’t many Ps in each condition, (only 15 people did the acoustically similar condition), with a sample size this small, there could be anomalies - Those who volunteer are more likely to enjoy taking memory tests and have a better memory which will skew the average
R: Standardised instructions mean that the experiment could be repeated in order to test validity of results
A: Baddeley was able to apply this research into creating a new memory model called the WMM, (which he did with Hitch), this model was seen as being more reliable than MSM
V: The study was carried out in a lab, meaning that it lacked ecological validity - It could also be argued that the fact they had to reorder the lists meant the task lacked mundane realism, as this is not something someone would have to do in day to day life
SR
According to MSM
- First store of MSM
- It detects stimuli from our senses
- Capacity = Large
- Duration = 0.5-2s
- Coding = Depends on the sense that is picked up
- Each sense has a sub-store, for example, the echoic store codes auditory information
- A large capacity was proven by Sperling’s study - Outline the study in breif detail
STM
According to MSM
- STM is a unitary and passive store
- Capacity = 7±2 - Capacity can be improved through a process known as chunking
- Ex of Chunking: It is easier to remember a 12-word sequence if we break it up into 3 - 4-word sequences
- Duration = 18-30s
- Coding = Acoustic
- Study to support the fact coding is acoustic = Baddeley - When answering questions breifly outline the study and results
LTM
According to MSM
- LTM is a unitary store
- Capacity = Unlimited
- Duration = A lifetime
- Coding = Semantic
- Duration is evidenced by the fact that older citizens over the age of 80 can still recall events from their childhood
- Coding is evidenced by the Baddeley study, which should be outlined if asked about LTM in a 4 or 6 marker
- Although LTM has an unlimited capacity, we do sometimes forget information, however, this is not due to the capacity of our LTM
**
Chunking
A method of increasing the capacity of our STM by grouping items together
Breifly outline Sperling’s study
- 3x4 grid of letters were shown to Ps for 50 milliseconds
- Ps then listend to different tones, which indicated which row they had to recall
- Some Ps were asked to recall the whole grid
- Recall of letters when a row was indicatede at random was high, which suggests all entire grid was stored in our sensory register
- However, because it has such a short duration, sometimes the grid faded before Ps could finish recall
- This indicated the capacity for the sensory register is large