Memory evaluation

Question 1

Capacity studies

Answer 1

• Joseph Jacobs, average span 9.3 for numbers, 7.3 for letters
• George Miller magic number, 7 plus or minus 2, 5 words 5 letters

Question 2

Capacity evaluation

Answer 2

• Cowan 2001 – reviewed a variety of studies on the capacity of STM and concluded that STM is likely to be limited to about 4 chunks, this suggests that STM may not be as extensive as first thought
• Research on the STM for visual information found that 4 items was the limit therefore the lower end of millers range is more appropriate
• Simone 1974 found that people had shorter memory span for larger chunks such as 8 word phases then smaller chunks such as one-syllable words
• STM capacity is not the same for everyone
• Jacobs found that recall increased with age – eight year olds could remember 6.6 digits whereas 19 year olds could remember 8.6 digits
• The STM increase may be due to a gradual increase in brain capacity or the idea that people develop strategies to improve their digit span as they get older

Question 3

Duration studies

Answer 3

STM - Lloyd and Margaret Peterson - studied duration, 24 students were given a consonant syllable and three digit number, intervals of 3,6,9,12,15,18, participants were 90% on 3 seconds and 2% on 18 seconds
LTM - Bahrick et al - 400 people aged 17-74, photo recongition and free recall name list of participants, 15 years afterwards and 48 years afterwards
photo recognition = 90% then 70%
free recall - 60% then 30%

Question 4

Duration Evaluation

Answer 4

• Trying to memorise constant syllables does not truly reflect most every day memory activities where what we are trying to remember is meaningful
• However we do try to remember groups of numbers and letters e.g. phone number and postcodes so does have some relevance
• In the Peterson’s study participants were counting numbers in their STM and may displace or overwrite the syllables to be measured
• Reitman 1974 used auditory tones instead of numbers so displacement tones would not occur he found that STM duration was longer suggesting that displacement in the Peterson’s study was due to displacement than decay and was not measuring the duration of STM
• Nairne et al 1999 – found that items could be recalled after 96 seconds

Question 5

Coding studies

Answer 5

• acoustic and semantic coding
• Baddeley 1966a and 1966b
• test effects of acoustically and semantically similar words
• if the words were acoustically similar than had difficulty remembering them in STM but not LTM suggesting that STM is acoustically coded
• if the words were semantically similar then they had difficulty remembering them in LTM but not STM suggesting that LTM is semantically coded

Question 6

Coding evaluation

Answer 6

• Frost 1972 – showed that long term memory recall was related to visual as well as semantic categories and Nelson as Rothbart 1972 found evidence of acoustic coding in LTM
• Varies according to circumstance
• Some experiments have shown that visual codes are used in STM
• Brandimote et al 1992 – found that participants used visual coding in STM if they were given a visual task and prevented to do an verbal rehearsing in the retention interval they had to say la la la before performing a visual recall task therefore they only used visual codes
• Other research has shown that STM sometimes uses a semantic code such as Wickens et al 1976
• STM was tested by asking participants to recall a word from a list immediately after hearing it whereas LTM was tested by waiting 20 minutes which is questionable whether this was LTM or not

Question 7

Multi store memory model evaluation

Answer 7

Strengths
Supporting evidence
- Controlled lab studies on capacity duration and coding support the existence of a separate short term and long term store which is the basis of the MSM
- Studies using brain techniques have also demonstrated that there is a difference between STM and LTM
- Beardsley 1997 – found that the prefrontal cortex is active during STM but not LTM tasks
- Squire et al 1992 – also used brain scanning and found the hippocampus is active when LTM is engaged

Case studies
- Different parts of the brain are involved in STM and LTM – from case studies with brain damage
- Scoville and Milner 1957 – brain damaged patient, his brain damage was caused by an operation to remove the hippocampus from both sides of his brain to reduce the serve epilepsy he suffered, HM personality and intellect remained intact but he could not form new LTM’s although he could remember things before the surgery
Limitations
The multi-store model is too simple
- MSM suggests that both STM and LTM are single unitary stores – research does not support this
- Research shows that STM is actually divided into a number of qualitatively different stores – it isn’t just a difference in terms of the kind of memory that is stored there
- The same is true for LTM – number of qualitatively different kinds of LTM each behave differently for example maintenance rehearsal can be explained by long term storage in semantic memory but idoesn’t explain long term episodic memories

Long term memory involves more than maintenance rehearsal

• Craik and Lockhart 1972 – suggested that enduring memories are created by processing that you do rather than through maintenance rehearsal, things that are processed more deeply are more memorable because of the way that they are processed
• Craik and Tulving 1975 – give participants a list of nouns and asked a question that involved shallowed or deep processing – asked whether a word was printed in capital letters or asked whether the word fitted in a sentence, the participants remembered more words in the task involving deep processing rather than shallow processing, this deep elaborative processes is a key process in creating long term memories

Question 8

The working memory model Evaluation

Answer 8

Strengths
Dual task performance
- Hitch and Baddeley 1976 supported the existence for CE in a study
- Task 1 occupied the CE, participants were given a statement “A is followed by B” and shown two letters “BA” and asked to say true or false
- Task 2 involved the articulatory loop e.g. say “the the the” repeatedly or involved both the central executive and the articulatory for example saying random digits
- Task 1 was slower when task 2 involved both the central executive and the articulatory loop, this demonstrates the dual task performance effect and shows that the CE is one of the component of the working memory model

Evidence from brain-damaged patients

• Shallice and Warrington 1970 – studied a man called KF, his short term forgetting of auditory information was greater than that of visual stimuli, his auditory problems were limited to verbal material such as letters and digits but not meaningful sounds therefore his brain damage was restricted to the phonological loop
• Another patient SC, had good learning abilities with the exception of being unable to learn word pairs that were presented out land, therefore had damage to the phonological loop – Torjano and Grossi 1995
• Farah et al 1988 – LH had been involved in a road accident performed better on spatial tasks rather than those involving visual imagery suggesting separate visual and spatial systems

Limitations
The central executive
- Some psychologists think it is just the same as paying attention, too vague and doesn’t really explain anything
- Critics believe that one CE is wrong and it is probably made up of different components
- Eslinger and Damasio 1985 studied EVR they had a cerebral tumour removed, but performed well on tests requiring reasoning so his CE was still intact, but he had poor decision making skills therefore he would spend hours trying to decide where to eat this suggests that the CE was not fully intact
- The account offered of the CE is unsatisfactory because it fails to explain anything as its probably more complex

Evidence from brain damaged patients

• Brain injury is traumatic this may change behaviour so that a person performs worse on certain tasks
• May have difficulties paying attention and therefore underperform on tasks

Question 9

Evaluation of types of long term memory

Answer 9

Evidence from brain scans

• Three types of memory is supported by brain scans, it has been shown that different areas of the brain are active when the different kinds of LTM are active
• Episodic memory = hippocampus and other parts of the temporal lobe and the frontal lobe, memories of different elements of an event may be distributed in other areas but are all connected by the hippocampus to form one episode
• Semantic = temporal lobe
• Procedural memory = cerebellum – this is involved in the control of motor skills and the motor cortex, basal ganglia and limbic system are also involved

Distinguishing procedural and declarative memories

• HM – destruction of hippocampus affected the ability to make new long term memories but his old ones were intact, so basically he could still form new procedural memories but not episodic or semantic memories
• Corkin 2002 discovered that he could draw a figure by looking at reflection in a mirror which is procedural memory but had no memory that he drew it which is episodic/semantic memory

Distinguishing episodic and semantic memories

• Relationship between the episodic and sematic memories raise the question of whether episodic memories are a gateway to forming semantic memories or whether semantic memories can form independently
• Hodges and Patterson 2007 – studied patients with Alzheimer’s disease and found that some patients retain the ability to form new episodic memories but not semantic memories, therefore this is a single dissociation
• Not sufficient enough evidence that two are distinct as the episodic memory could be placing greater general demand on the mental processing and that’s why it is more affected by brain damage – therefore researches need to look for double dissociation
• Irish et al 2011 was an example of double dissociation – found Alzheimer’s patients have the reverse – poor semantic memories but intact episodic memories suggesting that semantic memories could form independently

Evidence from patients with brain damage

• Low population validity
• HM – difficult to be certain of the parts of the brain that have been damaged until the patient has died
• Damage to a particular area does not mean that the area is responsible for that behaviour, may be acting as a relay station

Priming and a fourth kind of LTM

• Priming describes how implicit memories influence the responses a person makes to a stimulus - for example if a person is given the word yellow and then asked to name a fruit later the chance that they name banana is greater than if they are not primed – answers are automatic and unconscious
• Research has shown that priming is controlled by a brain system separate from the temporal system that supports explicit memory – lead to suggestion that there is a fourth kind of LTM, the perceptual representation system memory (PRS) – automated enhanced of a specific stimulus
• Spiers et al 2001 – studied memory in 147 patients with amnesia – all procedural memories and PRSs were intact but other two systems were not this supports the notion of two kinds of implicit memory not affected by amnesia

Question 10

Explanations for forgetting: interference studies

Answer 10

• retroactive - George Muller - gave participants a list of nonsense syllables to learn for 6 minutes and then after a retention period they were asked to recall the lists, performance was less good if participants had been giving intervening tasks between initial learning and recall - shown paintings and asked to describe them
• proactive - Underwood 1957, analysed findings from a number of studies and concluded that when participants have to learn a list of words they do not learn the list of words encountered later on in the sequence as well as the list of words that they encounter earlier on
• similarity of test materials - McGeoch and McDonald experiemented with teh effects of similarity of materials, gave participants a list of 10 adjectives during whcih they learned list B followed by a recall, if list B was synonyms they performed worse that if it was a list of non sense words
• real world study - Baddeley and Hitch and the Rugby players

Question 11

Explanations for foregetting: interference evaluation

Answer 11

artificial research

• Evidence that supports PI and RI, but most of the experiments are lab based and often use artificial and contrived equipment therefore does not relate to everyday memory
• Low ecological validity – participants may lack motivation to remember the lists which allows interference to have more of an effect
• On the other hand interference has been observed in everyday situations

only explains some situations of forgetting

• Interference effects do not occur often
• Special conditions are required for interference to lead to forgetting so therefore it is relatively unimportant
• Anderson 2000 concluded that interference plays a role in forgetting but how much is plays a role is unclear

accessibility versus availability

• Researchers question whether interference effects actually cause a memory to disappear or are just temporary
• Ceraso 1967 – found that if memory was tested after 24 hours there was spontaneous recovery whereas recall was the same, so interference occurs because memories are temporarily not accessible rather than lost

Real world application to advertising

• Danaher et al 2008 – found that both recall and recognition of an advertisers message were impaired when participants were exposed to two advertisements for competing brands within a week – serious problem considering the amount of money advertisers spend only to have the effect dulled by interference
• Suggest that one strategy might be to enhance the memory trace by running multiple exposures to advert in one day rather than spread out over a week which reduces interference

individual differences

• Evidence that some people are less affected by PI than others
• Kane and Engle 2000 – demonstrated that individuals with a greater working memory span were less susceptible to PI than those with a low span
• Having a greater working memory span meant having greater resources to consciously control processing and counteract the effects of PI

Question 12

Explanations for forgetting: retrieval failure studies

Answer 12

• Encoding specificity principle - Tulving and Pearlstone, demonstrated the value of retrieval cues where participants had to learn 48 words belonging to 12 categories, then recall either free or given category name
• Context- dependent forgetting - Abernethy 1940 - arranged for a group of students to be tested before a course then in the same room with same instructor, or difffernet room, or different instructor
• State-depending forgetting - Goodwin et al - drunk or sober

Question 13

Evaluation of explanations for forgetting; retrieval failure

Answer 13

lot of research support

real world application

• use it to improve recall
• Abernethy’s research suggests that you should revise in the room where you take the exam, may be unrealistic but you can use your imagination
• Smith 1979 - showed that just thinking of the room where you did the original learning was just as effective as doing the test in the same room

retrieval cues do not always work

• really not that effective to improve exam performance
• the information that you are learning is related to a lot more than just cues therefore it does not work
• learning complex associations which are less easily triggered by cues - outshining hypothesis - a cues effectiveness if reduced by the presence of better cues
• Smith and Vela 2001 - context effects are largely eliminated when learning meaningful material

the danger of circularity
James Nairne 2002 - criticised what he calls the myth of encoding-retrieval match
- claims that the relationship between encoding cues and later retrieval is a correlation rather than a cause - cues do not cause retrieval but are just associated with retrieval
Baddeley made a similar criticism
- pointing out that the encoding specificity principle is impossible to test because it is circular - if a stimulus leads to the retrieval of a memory that it must have been encoded in memory if it does not lead to a retrieval of a memory then according to the encoding specificity principle it cannot have been encoding but it is impossible to test for an item which has not been encoded

retrieval failure explains interference effects
Tulving and Psotka 1971 - demonstrated that interference effects are due to the absence of cues
- participants were given 6 different word lists to learn each consisting of 24 words divided into 6 different categories
- after each word list was presented they were asked to write down how many they could remember
after all the lists were presented they were given the category names and asked to recall all the words from the lists, the categories acted as cues
- some participants only learned one list, then other learned 2 and so on
- according to interference theory the more lists a participant had to learn the worse their performance would become
- However when participants were given cued recall effects of interference disappeared - participants remembered 70%of the words regardless of how many lists that they have been given - shows that information is there but cannot be retrieved and shows that retrieval failure is more important explanation of forgetting that interference

Question 14

Accuracy of eyewitness testimony; Misleading information studies

Answer 14

• Loftus and Palmer
• conformity effect
• repeat interviewing

Question 15

Accuracy of eyewtiness testimony: misleading information evaluation

Answer 15

Research support

• Research supports this
• Loftus conducted a memorable study involving cut outs of bugs bunny, and college students were asked to evaluate advertising material about Disneyland, and embedded in this material was misleading information about bugs bunny or Ariel and these could not have been seen in Disney
• participants were assigned to the Bugs, Ariel or control condition and all had visited Disneyland
• participants in the Bugs or Ariel condition were more likely to report that they had shaken hands with the characters than the control group

EWT in real life
Loftus research suggeted that EWT was unreliable but not all researchers agree
- Loftus may not represent real life because it was carried out in lab conditions
- Foster et al - found that if participants thought they were watching a real life robbery and also thought that their responses would influence the trial their identification of a robber was more accurate
- Yuille and Cutshall found evidence of a greater accuracy in real life, witnesses to an armed robbery in Canada gave accurate reports to the crime four months after it had taken place even though they had initially been given two misleading questions suggesting that misleading information may have less influence on real life EWT

real world applications

• Criminal justice system relies of EWT and identification in prosecuting crimes
• psychological research has been used to warn teh justice system of problems with EWT
• DNA exoneration cases confirm this showing that eyewitness identification was the largest single factor contributing to the conviction of innocent people

individual differences

• Age differences could be consequence of source monitoring
• eyewitness acquires information from two sources from observing the event itself and from subsequent suggestions
• number of studies have found that compared to younger subjects elderly people have difficulty remembering the source and become prone to the misleading information

may be response bias

• Bekerian and Bowers suggested it might be a response bias after all and they compared participant performance in two conditions
• in one condition participants were given a set of questions which matched with data that was consistent or inconsistent, they were later asked the same questions but in a different order
• participants were less accurate when the data was inconsistent
• in condition 2 participants were given the same task but this time the set of questions were presented in the same order and there was now a difference between having been giving consistent or inconsistent data this suggests that the order of questions had a significant effect and therefore memory change was due to response bias not storage

Question 16

Accuracy of eyewitness testimony: Anxiety studies Evaluation

Answer 16

Weapon focus may not be caused by anxiety

• Pickel 1998 proposed that the reduced anxiety of identification due to the weapon focus effect could be due to surprise rather than anxiety,
• Arranged a thief to enter a hairdressing salon carrying scissors – high threat, low surprise- handgun – high threat high surprise , wallet – low threat low surprise, whole raw chicken – low threat, high surprise
• Identification was least accurate to high surprise conditions than high threat conditions 0 supports the idea that weapon focus effect is related to surprise rather than anxiety

real life versus lab

• Anxiety done in context of real crime – Christianson and Hubinette – lab studies to do not create real levels of anxiety experienced by a real eyewitness during a real crime
• Deggenbacher et al – agreed with this, but found from a review of 34 studies that lab studies demonstrated that anxiety led to reduce anxiety, and real studies are associated with an even greater loss in accuracy which contrasts with Christianson and Hubinette

no simple conclusion

• Study of Christianson and Hubinette – concerned a violent real life crime – many other studies of anxiety and accuracy of identification, even the real-life ones did not involve violence
• Halford and Milne found victims of violent crimes were more accurate in their recall of crime scene information that victims of non-violent crimes – shows no simple rule about effect of anxiety on accuracy of eyewitness testimony

individual differences

• Emotional sensitivity is an individual difference
• Bothwell et al – participants were assessed for neuroticism, a personality characteristic where individuals tend to become anxious quite quickly – they were labelled neurotic and stable, the participants that were stable showed rising levels of accuracy as stress increased whereas the opposite for neurotics
• Deffenbacher et al – pointed out that modest effect sizes may be the result of averaging out low accuracy and high accuracy scores of sensitive and non-sensitive participants respectively

an alternative model

• Fazey and Hardy suggested a more complex relationship between anxiety and performance than the Yerkes-Dodson model
• Catastrophe theory predicts that when physiological arousal increases beyond the optimum level, the inverted-U hypothesis predicts a gradual decrease in performance Fazey and Hardy observed that in fact there is sometimes a catastrophic decline which they suggest is due to increased mental anxiety
• The inverted U describes increased physiological anxiety – fits real life eyewitnesses

Question 17

Improving the accuracy of eyewitness testimony: The cognitive interview Evaluation

Answer 17

Research into the effectiveness of the cognitive interview

• Meta-analysis of 53 studies found on average a 34% increase in the amount of correct information generated in the CI compared with standard interviewing techniques although they involved volunteer witnesses tested in a lab
• The effectiveness of the CI may be due more to some individual elements rather than the whole thing
• Milne and bull 2002 – interviewed undergraduate students and children using one individual component of the CI and compared responses to a controlled condition where they were instructed to “try again” recall across the four individual components was broadly similar and no different to the control group – when did a combination of the report everything and mental reinstatement components of the CI there recall was higher than all other conditions

quantity versus quality

• Procedure is designed to enhance the quantity of correct recall without compromising the quality of that information however the effectiveness has largely been in terms of quantity
• Kohnken et al found an 81% increase in correct information but a 61% increase of incorrect information when enhanced CI was compared to incorrect information therefore police need to treat all information collected from CI carefully

problems with using the CI in practise

• Kebbel and Wagstaff report a problem with CI in practise, police offers suggest that is requires more time which they do not have so use deliberate strategies aimed to limit an eyewitness report to the minimum amount of information that the officers feel is necessary
• CI requires special training and many forces cannot provide it in a few hours therefore it is not widespread

difficulties in establishing effectiveness
- Used in the real world but is not one procedure but a collection of related techniques for example thames valley police use a version that does not require changing perspective and other police forces that use the CI technique have only tended to use the reinstate context and report everything

individual differences

• CI important when interviewing older witnesses
• Negative stereotypes can make interviews overly cautious about reporting information however CI stresses the importance for reporting everything
• Mello and Fisher 1996 – compared older and younger men’s memories of a filmed stimulated crime using either CI or standard police interview, the CI produced more information than the SI but it was significantly greater for the older than younger participants