Every Study you need to know for AS Psychology - Atkinson and Shiffrin's Multi-Store Model of Memory
By the end of this Hub
You should be able to distinguish the following psychologists/patients, know how their relevant experiments were executed, and associate the correct dates with them all!
- Atkinson & Shiffrin
- Henry Molaison (HM)
- Sergei Korsakov
- George Armitage Miller
- Peterson and Peterson
- Alan Baddeley
- Craik & Tulving
You should also be able to talk about some of the weaknesses of Atkinson and Shiffrin's multi-store model of memory (1968) and this will lead you nicely into improved and more convincing models of memory.
Studies that Support Attkinson & Shiffrin's Model of Memory (1968)
What is Atkinson and Shiffrin's Multi-Store Model?
Atkinson and Shiffrin were the first to propose that our memory faculties are split into the following three parts:
- Sensory Register - the faculty we use to initially store information that we perceive in our senses e.g. an image is stored in the eyes. The capacity of the sensory register is around 9 times (Sperling) and items typically last for only 1/2seconds in this faculty.
- Short Term Memory (STM) - where the information goes to from the sensory register to be kept for recalling for a longer period of time - lasting around 18 seconds and holding around 7 items.
- Long Term Memory (LTM) - where the information is transferred to from the STM for potentially the rest of the holder's life.
The Korsakoff Syndrome Observation
The main symptom of Sergei Korsakoff's 'Korsakoff syndrome' is an amnesia-like state where sufferers forget what they perceive within seconds of perceiving it. However, they still maintain a normal LTM, providing even more evidence for the functional separation of our memory.
Korsakoff Syndrome - Just another reason to cut back
Amnesia Patient Henry Molaison (1953)
In 1953, a man suffering with seizures called Henry Molaison (often referred to as 'HM') underwent surgery that lead him to have amnesia.
This meant that he suffered damage to his LTM, making it impossible for him to make new long lasting memories - he could only remember things that happened before his operation!The fact that HM could only remember things for a matter of seconds provided great and almost undeniable evidence for the idea that we have some sort of functional separation of our memory facilities. Although HM could not transfer new information to his LTM, he could still use his STM and remember LTM memories he made before the amnesia.
Peterson and Peterson (1959)
- The average duration of information staying in the STM is 18 seconds
- Participants were given trigrams - mixtures of 3 different letters e.g. AQP - and asked to recall them after varying amounts of time (0-18+ seconds).
- Only 10% of participants could remember trigrams after 18 seconds
- Without rehearsal, the STM can only hold information for around 18 seconds
- With rehearsal, the duration of information that is held in the STM can be increased and according to the Peterson and Peterson model of memory it is through this rehearsal that information is transferred to the LTM from the STM
- This suggests that there is not LTM transfer unless there is rehearsal (this was proven to be incorrect by other models).
George Armitage Miller's 'Magical Number Seven' (1956)
- The capacity of the short term memory is on average 7±2 items
- Various experiments involving asking participants to look at information and then recall it shortly after.
- Participants would remember between 5 and 9 items on average, but this number would increase sometimes significantly if the participant used the 'chunking' technique of memorisation.
- Why our brains are on average only capable of holding seven items is not a question that has been thoroughly answered (yet) - at the moment, we know that it simply is the case.
Alan Baddeley (1966)
- LTM stores information semantically and STM stores information acoustically.
- Three independent groups were asked to memorise a list of words: one group had semantically similar words, the other acoustically similar words and the third was a control group with unrelated words.
- Immediately after recalling words, it was the acoustically similar ones that suffered most and semantically similar ones that were remembered best
- When asked to recall the words after 20 minutes, it was semantically similar words that were remembered worst.
- Although seemingly counter-intuitive, the results show that the STM uses an acoustic code because more erros were made when recalling acoustic words - this is because the memories clash with each other and make it difficult to recall the correct words. The same logic is applied to the LTM and semantically similar words leading us to believe that the LTM functions using a semantic code.
Joke to Remember:
- The psychologists tried to figure out how the LTM and STM stored information - it went Baddeley.
- Came up with evidence for the 'primacy and recency effect'.
- Participants were asked to memorise a pre-made list of words fed to them in 2 second intervals and then recall them in any order.
- Participants would be much more likely to remember the first and last words of the list they were given.
- Words at the start of the list would be consolidated into LTM
- Words at the end of the list were still in the STM of the participants when recalling occurred
- Middle words were displaced by the words following them because the STM can only hold on average 5-9 items and there hadn't been enough time for them to be consolidated into LTM.
Craik and Tulving (1975)
- Showed that we are more likely to store information in LTM if it has a 'deeper' meaning to us.
- Participants were told 3 lists of 60 words one word at a time with each list containing either 'deep,' 'intermediate,' or 'shallow' words and were asked to identify which of another 180 words were present in their first 60 word list.
- The 'deepness' of words was gauged by using different questions such as 'is this word in capital letters' for shallow words and 'does with word rhyme with ..." for an intermediate word.
- 65% of deep level words were successfully identified
- 37% of intermediate level words were identified
- 17% of shallow were identified
- For some reason, the brain processes words that we give more meaning to better than words that have little meaning to us - this may be because there are more neuronal connections made for words that we associate with many other things.
Criticisms of Shiffrin & Atkinson's Multi-Store Model of Memory (1968)
The main criticism of the model is that it is just too simple - if evidence is provided for the idea that our memory is split into different parts it doesn't necessarily mean that it is split into just two or three parts, it could be millions, and it is too optimistic to suggest that the brain would work so simply as to use only an acoustic semantic code and that each of these are restrained to one of two faculties of memory.
The KF Observation
KF was a man who suffered from memory problems after a motorcycle accident.
- Surprisingly, it was his LTM that was fully functional - he could make new long lasting memories. His STM on the other hand was severely impaired, with only a capacity of two items instead of the average seven that George Armitage Miller proposed in 1956.
- If this was really the case, then how could KF possibly have had a fully functional LTM?If the source of the information (the STM) was severely impaired, then by Atkinson and Shiffrin's model so should KF's LTM have been impaired.
A Summary, A Story and then a Quiz
Now that you have read everything and have held it in your STM, you must rehearse the information and reinforce the memory - increasing its chances of being transferred to your LTM for use in exams!
Below is a streamlined summary of the figures you just read about and their contributions to psychology.
- Atkinson & Shiffrin (1968) - inventors of the multi-store model of memory
- Henry Molaison 'HM' (1953) -- a sufferer of anterograde (post-surgery) amnesia could not use make new LTM memories but maintained a healthy STM
- Sergei Korsakoff - the neuropsychiatrist who studied patients that could not remember things they had only just perceived a few seconds before
- George Armitage Miller (1956) - found that the average number of items our STM can hold is 7 items
- Peterson and Peterson (1959) - found that the duration of information in the STM is 18 seconds
- Craik & Tulving (1962) - found that we are more likely to remember words that have a 'deeper' meaning
- Alan Baddeley (1966) - found that the STM uses an acoustic code whilst the LTM uses a semantic code
- Murdock (1975) - provided evidence for the primacy and recency effect
The Importance of Stories
Remember, memorising long lists of things is a lot easier through stories and pneumonics - this gives words a deeper meaning through creating more neuronal links the information you're trying to remember
Below is an example story that you could have made, this is the one I use and although it might seem like the similarities between the story words and the psychologists I'm remembering are quite large, because I was the one who came up with it all it does not seem like that to me - I'm the one who came up with it in the first place!
Essentially, I'm built a story with words that I know will lead me to the names of the psychologists I'm trying to remember. For example, Shuffrin to me sounds like shuffling and also Shiffrin, so If I use that word in my story I can use it as 'shuffling' which will remind me of "Shiffrin'. Shuffrin -> Shuffling -> Shiffrin.
The Peat Bogs of Georgia
Bolded words are the stimulus words that will remind me of the psychologists!
I was Shuffrin through a local H&M store in Georgia
When I saw a man, Peter, who was stuck in a Peat bog
The man cried "ouch ouch my legs are Craiking so Baddeley!"
In the end he sadly died, the village people said it was Murder.
You now have a superior understanding of the proofs we have for what we know about our memory and can feel so much more confident when entering in your next pub quiz or watching ITV's University Challenge.
On top of that, you might just get that A grade you were striving for in Psychology.
But just so that this becomes an unforgettable experience for you, take the Quiz below and prove to yourself that your STM and LTM is fully functional!