- Created by: Jenna k
- Created on: 12-04-14 10:56
Multi-store model of memory
Atkinson and Shiffrin proposed a model of memory in 1968. They suggested that information travels through the model in a linear and strategic way. They said that there wasa sensory store, which recieved information for the senses. If paid attention to it would move the the short term memory where is would be rehearsed enough to go into the long term memory where it would be stored. From the long term memory this memory would be able to be retrieved and used.
This is a diagram of the multi-store model.
Sensory store: Duration
In 1960 Spearling conducted a labortaory experiment with the aim to find the duration of the sensroy store.
He did this by showing his participants a grid of four by three letters. This slide was flashed up on the screen for 50 milliseconds. The participants were then asked to recall as many of the letters as they could. He found that, on average 4 out of the possible 12 were remembered. However the particpants were still aware that there were more letters, they just could'nt recall them.
He then decided to add sounds into each line that apeared. When recelling he played each lines tone and asked them to recall as many as they could from a line at a time. This increased the recall to 9 out of the possibe 12 letters.
These findings showed that the image of the grid was remebered however will recalling this picture was fading. Thus Spearling conculded that the duration of the sensory store memory was 1-2 seconds.
He also suggested that there are a number of different stores before the sensory memory that feed into the sensory store. This will be dicussed on the next page.
Sensory Store: Encoding
In 1988 Baddeley suggested further evidance of the stores before the sensroy memory.
He thought that there must be a visual store that condugates all the imaged we see and makes them a continuous flow of images, like a movie instead of a whole bunch of stills. He called this store the iconic store.
He then suggested this would be the same for all our other senses. So there is the econic (hearing) and haptic (touch) stores as well.
Short term memory: Duration
In 1959 a married couple, Peterson and Peterson conducted a labortory experiment with the aim to find the duration of the short term memory.
They did this by showing their participants a triagram (Three letters) and asking them to memorise it. Whilest trying remember the trigram the participants had to do a distractor task of counting backwards in three's . The suration of the exercise started at 3 seconds and was increased to 18 seconds.
They found that 80% of the participants remebered the trigram after 3 seconds of the distractor task. But this decreased to 10% when the distractor task lasted 18 seconds.
From this they conculded that without rehersal memory decayed rapidly in the short term memory. From this we know that the duration of the short term memory is about 20-30 seocods long.
Short term memory: Encoding
In 1964 Conrad conducted a an experiment with the aim to determine how we encode information in our short term memory.
He did this by asking ti remember a squence of 8 letters. In codition 1 all the letters where acoustically similar (BVE). In condition 2 they were all acusitcly dis-similar. (AWX)
He found that pearticipant woudl remeber the aucositcally disimilar letters beter than the similar letters.
He concluded that the short term menory encodes aucustically.
However the short term also encodes visually and semanticly (physical charactoristics and meaning)
Posner and Kelle did an experiemt in 1967 where they asked participants to read out a list of numbers. B-B-B-b-A-B. They wer looking for a delay in the time to say B and b. They found that there was a time of 1.5 seconds but this visual process was very quicky over come a converted to an aucoustic process. Thus showing that there is a visual encoding process but the acoustic code is more frequently used.
Short term memory: capacity
In 1956 Miller conducted a experiment with the aim to find the capacity of the short term memory.
He did this by getting his participants to memories a list of nine numbers. He found on anverag that 7 were remebered correctly. However there were induvidual charactoristics that set the limits, of 5 -9. Thus he concluded that the capacticey of the short term memory was 7+-2.
However he went on study how we could improve this. He got the participants to memories the numbers while chuncking them, so instead of 1 2 3 4 5 6 7 8 9 there were 12 34 45 56 78 91 01 11 21. This made it possible to remember twice the amount.
This is not needed just I find it interesting as an add on to Miller.
There have benn further experiment to show that conxectuality also improve short term and long term memory. A study similar to millers was done with football fans and non-foor ball fans. They were asked to remember the list of numbers. The non-footbal fans found this task difficult as they could not find any sequence to the numbers. However the football fans did exceptionally well, becasue they had found a paturn of the matches wone by the team they supported. This shown that chuncking can be helped by prior knowledge.
Long term memory: Duration
In 1975 Bahrick et al conducted a study with the aim to find the duration of memories in the long term memory.
They used a sample of American classmates 34 years after they graduated. They showed pictures to the students induvidually and asked them to name everyone in the picture with no time limit. They then asked then to name all of themin a group, once again there was no time limit.
They found that induvidually they remebered 90% of the people in the pricture correctly. And in the group all were remebered correctly.
He found form the missing 10% that memories can decay and be interfered with to make our memory less reliable.
Long term memory: Encoding
In 1966 Baddley conducted a study with the aim to prove that we encode symatically in our long term memory.
He did this by a similar process to Conrade in 1964, where the participants had to memories a list of acoustically similar and dissimilar words. However in Baddleys experiment they had to remember lists of symatically similar and dissimilar words. Eg Boot, shoe, wheel, trainer, sandle (symaticaly similar) aposed to Chicked, shoe, salade, comutor, love, lava (symatically disimilar) He waited 20 minutes for the participants to learn and convert the list to long term memory.
He found that the symatically dissimilar word were recalled more accurately than the similar ones.
Thus he conculded that the long term ecodes symatically, for meaning.
Clive Wearing: case studys for the MSM
Mr Wearing moery was damaged by a viruse. He has forgotten everything for the last six years. His memory lasts on average 30 seconds, and then he forgets it. His wife has suggested that he writes down whenever he is feeling ‘conscious’ but as he moves on to the next 30 seconds he thinks that his last note was written when he was not ‘conscious’. This tragic story proves the existence of the separate components of the Multi-store model of Memory because his average ‘conscious’ period is 30 seconds long.
His sensory store must still be working as he is still seeing and hearing things as he pays attention to them. His long term memory still works although it has been damaged, because he can still play the piano like he did before the accident. It’s only his ability to rehearse the information in his short term memory that is been affected. This means that the information is displaced every 30 seconds.
Multi-store model of memory: evatuation
- There are a lot of studies that have prove the existance an the validity of the model.
- There are case studies that show existance of damage to single stores and not the whole system.
- Has provided a foundation for other testable psychological model and thories to be formed.
- It is exteramly simplified for our complex memories and processing abilities.
- The role of rehearsal is exadurated as it is not a proven method of memory. It also has aposing ideas such as flash bulb memory, which seems to bipass the Systematic process that Atkinson and Shiffren thought was so important.
- In addition we have developed other methods that also arent explained by the multi store model of memory. Such as mind maps and mnumonics.
- Fails to take into account the different things were are likey to remeber. It only focuses on *** much information we can remember not the nature of this information, whether it by interesting, funny or scarey.
Working Memory model
In 1974 Baddley and Hitch developed a model of memory that looked more in detail at the short term memory. As Baddley said that the multistore model over simplified the conplexity of our minds.
Together they created The Working memory model, which consisted of The central executive and its two salve sytems the Phonological loop and the Visuo-spacial sketch pad.
In 2000 the Episonic buffer was added as a means to transfer memories to the long term memory.
This is theworking memeory model.
The central executives role is to encode information symatically and initiated and suporvise what the salve systems are doing. It may be a limited capacity store but it is able to process all types of sensory information form the haptic, iconic and econic store. I addition it tasks manages, delegates and starts the process of rehearsal. So just like a real boss, It just tells you want o do and does nothing for itself.
To prove the existance of the Central exercutive Baddey conducted a study involving participants remembering a list of 8 didgits while either counting up form one or doing the alpherbet. He then did the same this but with an alternation task, where numbers and letters were mixed up. A1B2C3D4.
He found that participants could not do this task. So it was conculded that they could not do it becasue both task or competing for the attention of the celtral executive. Thus showing that the Central executive is in control of initiating the rehearsal process and finding paturns and drawing on passed knowlegde.
Visuo-spactial sketch pad
The visuo-spacial sketch pad is refered to as the inner eye. It is the slave system that process and stimulaes visua infromation.
There are two sub systems to the visuo-spacial sketch pad, the inner scribe and the visual cache where Baddley said rehearsal takes place.
To prove the existance of the visuo-spacial sketch pad Baddley conducted anther study in 1973 which consited of asking his participants to follow a moving light spot while visualising a block capital and indentifying if the light touched one of the corners.
He found that participants could not do this. Thus he conculde that both the tasks were cometing for the same resources and could not be processed similtaneously.
Baddely did a varation of this study however he replaced the visualising task for a repitition task, which participanst found a lot easier. Thus concuding that the they could complete this task due to the dual nature of the task. They could multi task as the information was not cometing for the same resources.
The phonological loop is a limited capactiy short term store that ecodes audiblely. It is sometimes called the inner voice as it deals with the econic store and audio processing.
Everdiance of the existance of the phonological loop is the research that Baddley conducted in 1975. He asked his participants to remember a list of momosylobol words and recall them straight away. He then tried it will polysyoloble words. He found that the participant struggeled to memorize the longer words. Thus suggesting that the phonological loop deal with the length of the word and not what it means. It is sggested that the maximum time it can process is 1.5 seconds.
There are once again two sub sytems to the phonological loop, the articulatory control system and the ponological store.
In 1970 Baddley suggested that the Articulatroy control system is a passive storeage sytem that holds words that have been maintained in the short term memory by subvocal repitition. Baddley conducted a smaller study consiting of chanting a meaningless chant and processing larger words. He found that they were processed differently. The chant was procesed by the phonological store where as the larger words were processed by the ACS. Thus proving the excitance and role of the two sub systems.
Evaluation of the Working Memory Model
- Because there is more detail and evidance showing how the short term memory works, it is more plausable. It also inculdes rehearsal options and alternative processing methods that Atkinson and Shiffrin failed to inculde.
- Findings form this model can be used to explain KF's case study where the multi-store modle was unable to.
- It can explain why people have induvidual processing methods. For example a child with Dyslexia will have a less funtions phonolgical loop and a more active visuo-spacial sketch pad.
- The working model only focuses on the short term forgetting about the long term and process to get the information to the long term memory.
- Berz (1995) critisied the model for not inculding musical memory as he had found that ausio tasks werent affected by the presence of music.
Eye witness testimony
Eye witness testimony is a legal term for a person that has witnessed a crime.
When talking anout EWT we have to think about people Schema's. Schema's are organised sytems of knowledge that we use to undertand and interpret the world. Schemata can disrupt our recall of events and it can be easily mislead, which conpletly changes all credibility of our memory.
There are three factors that can effect EWT:
- Misleading information.
To improve our EWT the investigators counduct a congnitve interview. This was developed to change the way we report our EWT and how accurate it can be.
- Context reinstatement > This is when the invesigator asks about other things that were going on at the time. Such as what shop you were in and what you wanted to buy.
- Report everything > This is were everything before, during and after the event happed.
- Recall in a chaged perspective > Descibing the event form the eyes of someone else at the scence.
- Recall in revers order > Changing the order you recall events can bring to light something you might have missed when telling the story in the convestional way.
EWT: Misleading information
Misleading information comes in the form of leading questions that could be accepted into our memories as the truth. This is called Misinformtion acceptance.
Loftus did a study in 1975 with the aim to find the extent that misleading information can disrubt truthfull EWT. She did this by grouping her participants into a control group and an experimental group. They both saw a movie showing the lead up to a crime. The control group were then asked questions about what they saw. The experimental group were asked misleading questions.
She found that 7% of the experimental group accepted the post-event information. 3% of the control group made the same mistake when asked misleading questions.
Thus she conculded that misleading information planted by the invesigators and talking to other witnesses about the event can twist our own truthful acount of what happened.
- Labitory experiment
Anxiety can decrease or increase a witnesses memory which can lead to unreliable and truthful reports.
Loftus did another experiment in 1982 to find the extent of infulacne of anxiety on EWT.
She asked participants to listen to an discution on a mechanical failure. In one condition the man walked out of the office with greese all over his hands. In the other condition he walked out witha knife in his hand which was covered in blood. When the witness were shown pictures of the men, she found that the recognition of the man with the bloodly hands was a lot lower than that with the greesy hands. She suggested that the recall was becasue the man had a knife which took their attention away form their face, so it was more difficult to remember the face. This is called the weapons effect.
She conculded that we get anxiesion around objects that can threten our suvival as it effects our recall of actuall events.
Some of the witness are children and older people which could affect their suggestablity or the reliablity of thier memory.
Poole and Lindsay did a study in 2001 where they asked 3-8 year old children to lsiten to a story their partents read to them. They were then questioned on their own knowledge on the topic. It was found that they used thier own knowledge but they also used the information form the story. The children where then asked were they got the information form. The older children said they got it from the stroy where as the younger children did not know.
This suggests that children are very accepting of misleading information becasue of their lack of knowledge and innicence, thus we can't reliy on them to give true accounts of the event.
Inproving your memory
There are a number of ways that you can improve your memory but these are the select few that you have to know.
Mnemonics > You can use what is known as a peg word. This is an association between two unrelated words however this is a very visual technique and uses the visuo-spacial sketch pad to its full. Alternatively you could use method of loci which is when you visualise a regular route such as that of the work to school and put information at certain points on the route.
Chunking > This makes long list more memerage as you are compressing the information in to smaller chunks.
Ecoding and retreival > Learning the information in the same place you are going to retreive the information is a good way of doing things. Alternatively you can study different subjects in different rooms and when in the exam recall the lay out of the room and what you learnt in it.
Practice and attention > Pay attention to what you sense and repeat it regularly in you mind so it will be transfered to long term.
Concret nouns> nous that can be easily visulised such as walking
Abstract words > wrds that can't be percieved by the senses such as love or nice.