Memory P1 Flashcards
1
Q
what is meant by coding?
A
it is the format in which information is stored in various memory stores
2
Q
what is meant by capacity?
A
the amount of information that can be held in a memory store
3
Q
what is meant by duration?
A
the length of time information can be held in the memory
4
Q
What is meant by short-term memory?
A
the limited capacity memory store
coding is mainly acoustic, capacity of 5-9 items, duration is about 18s
5
Q
what is meant by long-term memory store?
A
it is the permanent memory store
coding is mainly semantic, unlimited capacity and can store memories for up to a lifetime
6
Q
What is meant by acoustic?
A
the way a word sounds, e.g. cat,cab
7
Q
What is meant by semantic?
A
the meaning of the words e.g. large, huge, big
8
Q
Research into coding - Baddeley 1966, acoustic & semantic
A
he gave different lists of words to four groups of participants to remember:
-Grp 1 acoustically similar
-Grp 2 acoustically dissimilar
-Grp 3 semantically similar
-Grp 4 semantically dissimilar
found that immediate recall was worse with with acoustically similar words, STM is acoustic
recall after 20 mins, worse with semantically similar words, LTM is semantic.
suggest info is coded acoustically in STM and semantically in LTM
9
Q
Research into capacity, Jacobs 1887 testing digit span
A
researcher reads four digits and increases until ppt can’t recall the order properly
final number = digit span
- on average ppt’s could repeat back 9.3 numbers & 7.3 letters in the correct order immediately after they were presented.
10
Q
Research into capacity, Miller 1956, magic number 7+/-2
A
miller observed everyday practice, noted things come in sevens - notes of musical scale, days of the week, deadly sins etc.
miller thought span of STM is about 7 items + or minus 2 (5-9)
increased by chunking
11
Q
What is chunking?
A
grouping sets of digits/letters into meaningful units to remember more pieces of info
12
Q
Research into Duration of STM, Peterson & Peterson 1959, consonant syllables
A
24 students given a consonant syllable (YCG) to recall and a 3 digit number to count backwards from
the retention interval was varied: 3,6,9,12,15,18 seconds
found that after 3 seconds average recall was about 80%, after 18 seconds it was 3%.
this shows that STM duration w/o rehearsal is up to 18 seconds.
13
Q
Research into LTM duration, Bahrick 1975 yearbook photos
A
studied 392 americans aged 17-74
1. recognition test - 50 photos from yearbook, had to name them
2. free recall test - ppt’s listed names of their graduating class
they found for recognition 90% accurate after 15 years and 70% accurate after 48 years. for the free recall test - 60% recall after 15 years and 30% after 48 years. This shows that LTM may last up to a lifetime for some material
14
Q
A strength of Baddeley’s study is that it identified two memory stores.
A
Later research showed that there are exceptions to Baddeley’s findings. But STM is mostly acoustic and LTM is mostly semantic. -> this led to the development of the multi-store model
15
Q
A limit of Baddeley’s study is that it used artificial stimuli.
A
The words used had no personal meaning to the ppt’s so tells us little about coding for everyday memory tasks. When processing more meaningful information, people use semantic coding even for STM. This means the findings of this study have limited application.
16
Q
A strength of Jacobs’ study is that it has been replicated.
A
this is an old study and may have lacked adequate controls (confounding variables e.g. ppt’s being distracted. Despite this, Jacobs’ findings have been confirmed in later controlled studies e.g. Bopp 7& Verhaeghen 2005. This shows that Jacob’s study is a valid measure of STM digit span.
17
Q
A limit for millers study is it may overestimate STM capacity.
A
for example, Cowan 2001 reviewed other research. He concluded that the capacity of STM was only about 4 +/-1 chunks. This suggests that the lower end of miller’s estimate, 5 items, is more appropriate than 7 items.
18
Q
A limit of Peterson & Peterson’s study is the use of meaningless stimuli.
A
We sometimes try to recall meaningless things so the study isn’t completely irrelevant. But recall of consonant syllables doesn’t reflect meaningful everyday memory tasks. Therefore the study lacked external validity.
19
Q
A strength of Bahrick’s study is that it has high external validity.
A
Everyday meaningful memories e.g. of peoples faces and names, were studied. Shepard 1967 found When lab studies were done with meaningless pictures to be remembered recall rates were lower. This means that Bahrick’s findings reflect a more ‘real’ estimate of the duration of LTM.
20
Q
What is the multi-store model (Shiffrin &Atkinson) ?
A
describes how info flows through the memory system.
a representation of how memory works in terms of three stores called the sensory register, STM and LTM. describes how info is transferred from one store to another, what makes memories last and some disappear.
21
Q
What is meant by the sensory register?
A
the memory stores for each of our five senses such as vision (iconic) and hearing (echoic). coding in iconic SR is visual and in echoic SR is acoustic.
Massive capacity
info lasts for half a second
all stimuli from the environment pass into SR,
22
Q
How does the sensory register effect coding, capacity and duration?
A
coding - modality specific, depends on the sense
duration - very brief less than 0.5s
capacity - high e.g. over one hundred million cells in one eye each storing data
23
Q
how does the info transfer from SR to STM?
A
IF ATTENTION IS PAID TO THE INFORMATION - KEY PROCESS
24
Q
Describe elements of STM refering to msm
A
a limited capacity store of temporary duration
coding - acoustic
duration - 18 seconds, unless info is rehearsed
capacity - 7+/-2 items before some forgetting occurs, cowan argues for 5
25
How does info transfer from STM to LTM?
when we repeat material to ourselves, this is maintenance rehearsal - stays in STM, if we rehearse long enough it passes into LTM - prolonged rehearsal
26
describe elements in LTM REFER TO MSM
a permanent memory store
coding - mostly semantic
duration - potentially up to a lifetime
capacity - potentially unlimited
27
How is information retrieved from LTM?
when we want to recall info stored in LTM it has to be transferred back to STM to be recalled
28
a strength for MSM is research support showing STM & LTM are different.
Baddeley 1966 found that we tend to mix up words that sound similar when using our STMs, so STM coding is acoustic. But we mix up words that have similar meanings when we use our LTMs, shows LTM coding is semantic.
-> This supports the MSM's view that these two memory stores are separate and independent.
29
A counterpoint for strength of MSM
Despite such apparent support, the studies tend not to use everyday information e.g. faces and names. They use digits/letters or meaningless consonant syllables. Therefore the MSM may not be a valid model of how memory works in everyday life where memory tends to involve meaningful information.
30
A limit of MSM, is evidence suggesting there is more than one STM store.
In Shallice & Warrington 1970, KF had amnesia, STM recall for digits was poor when he heard them, but much better when he read them. Other studies confirm there may also be a separate STM store for non-verbal sounds e.g. noises. Therefore the MSM is wrong to claim there is just one STM store processing different types of information.
31
A limit of MSM is prolonged rehearsal is not needed for STM-LTM transfer
Craik & Watkins 1973 argued there are two types of rehearsal called maintenance and elaborative. Maintenance is the one described in the MSM but elaborative rehearsal is needed for long-term storage. This occurs when you link information to your existing knowledge, or think about it's meaning. This suggests that the MSM doesn't fully explain how long-term storage is achieved.
32
What is the case of HM?
-relate to MSM model
had brain surgery to relieve his epilepsy, his hippocampus was removed from both hemispheres
-when memory assessed in 1955, he thought it was 1953 & he was 27(he was 31)
-couldn't form new long term memories
-performed well in tests of immediate memory span, a measure of STM.
33
what is the study of Clive wearing?
- has a severe form of amnesia, damaged hippocampus
- before was a world-class musician, he could still play the piano brilliantly & conduct a choir, but couldn't remember his musical education
- he could remember his second wife's name and greets her when they meet, believing he hasn't seen her in years
34
what is the study of KF?
in shallice & warringtons 1970 study
- he was hit by a motorcycle
- poor STM for auditiory info, but could process visual info normally.
- immediate recall of letters & digits was better than when he read them over them being read to him
35
the three types of long term memory are?
Episodic
Semantic
Procedural
36
what is meant by episodic memory?
- stores events from our lives, linked to a diary of daily linked personal experiences
- memories are complex, time stamped - remember when they happened and how they relate in time,
- several elements
- make a conscious effort to recall them
37
A strength of types of long term memory is case study evidence of different types of LTM
Clinical studies of amnesia, HM & Clive wearing, showed both had difficulty recalling events that had happened to them in their pasts. But their semantic memories were relatively unaffected e.g. HM didn't need the concept of 'dog' explained to him. Procedural memories were also intact as clive could still play the piano & conduct a choir. This supports the view that there are different memory stores in LTM because one store can be damaged but other stores are unaffected.
38
A counterpoint to the strength of episodic memory
researchers lack control in clinical case studies - they don't know anything about the person's memory before the brain damage. Therefore clinical studies are limited in what they can tell us about different types of LTM.
39
what is meant by semantic memory?
stores our knowledge of the world
- a combination of an encyclopaedia and a dictionary.
e.g. includes memories of how an orange tastes
not time stamped
less personal than episodic more about facts/knowledge we all share
40
A limit for types of long term memory is conflicting finding about types of LTM and brain nerves.
Buckner & Peterson 1996
reviewed research findings and concluded that semantic memory is located in the left prefrontal cortex and episodic with the right prefrontal cortex. But other studies from Tulving 1994 have found that semantic memory was associated with the right prefrontal cortex and the reverse for episodic memory. This challenges any neurophysiological evidence to support types of memory as there is poor agreement on where each type might be located.
41
What is meant by procedural memory?
```
stores memories for actions & skills
-memories of how we do things
e.g. how to drive a car
recall occurs w/o awareness/effort
-they become automatic with practice -> explaining step by step procedure of changing gears is hard because you do it w/o conscious recall
```
42
A strength for types of long term memory is helping people with memory problems.
Memory loss in old age is specific to episodic memory, it is harder to recall memories of recent experiences although past episodic memories are intact. Belleville 2006 devised an intervention for older people targeting episodic memory, which improved their memory compared to a control group. This shows that distinguishing between types of LTM enables specific treatments to be developed.
43
eval extra for types of long term semantic & episodic the same or different?
More recently tulving 2002 has said episodic memory is a 'specialised subcategory' of semantic, an intact semantic memory can function w a damaged episodic but not vice versa. However, Hodges and Patterson 2007 found that some patients with Alzheimer's disease can form new episodic memories but not semantic ones. Therefore episodic and semantic memories are closely related but ultimately different forms of LTM.
44
what does the working memory model represent?
the STM store
suggests STM is a dynamic processor of different types of info using sub units co-ordinated by a central decision-making system.
concerned with 'mental space' that is active when temp storing and manipulating info
45
the Baddeley & Hitch 1974 working memory model
concerned with 'mental space' that is active when for example working on arithmetic problem or comprehending language.
46
what is the role of the central executive in the wmm?
the central executive allocates subsystems
- a supervisory role where it monitors incoming data, directs attention and allocates subsystems to tasks
- limited storage capacity
47
what is the role of the phonological loop in wmm?
consists of phonological store & an articulatory process
- deals with auditory info and preserves the order in which the info arrives
- Phonological store, stores what you hear
- Articulatory process, allows maintenance rehearsal, repeating sounds to keep in WM while needed
48
What is the role of the visuo-spatial sketchpad in WMM?
stores visual/spatial information when required
e.g. recalling how many windows your house has
Logie 1995 subdivided VSS into visual cache & Inner scribe
-VISUAL CACHE, stores visual data
-Inner scribe, records arrangements of objects in visual field
49
what is the role of the episodic buffer in the WMM?
added in 200
a temporary store for information
integrates visual, spatial, verbal info from other stores
maintains sense of time-sequencing, recording events that are happening
links to LTM
50
A strength of WMM is support from clinical evidence.
for example, Shallice & Warrington 1970 studied patient KFA who had a brain injury. His STM for auditory info was poor, shows damaged phonological loop but he could process visual information normally, shows an intact VSS. This supports the WMM view that there are separate Visual and acoustic memory stores.
51
A counterpoint for strength WMM support
Kf may have had other impairment which explained poor memory performance, apart from his damage to his phonological loop. This challenges evidence from clinical studies of brain injury.
52
Another strength of WMM is that dual task performance studies support the VSS
Baddeley's 1975 participants found it harder to carry out two visual tasks at the same time than do a verbal & visual task together, the same for two verbal tasks. This is because both visual tasks compete for the same subsystem in the VSS. There is no competition with a verbal and visual task. Therefore there must be a separate subsystem that processes visual input and also a separate subsystem for verbal processes.
53
A limit for WMM is a lack of clarity over the central execution
Baddeley 2003 said the central executive was the most important but the least understood component of working memory. There must be more to the CE than just being 'attention' e.g. it is made up of separate subcomponents. Therefore the Central executive is an unsatisfactory component and this challenges the integrity of the model.
54
EVAL extra for WMM is the validity of the model
Dual-task studies support the WMM because they show that there must be separate components processing visual and verbal information. However, these studies are highly-controlled and use tasks that are unlike everyday working memory tasks e.g. recalling random sequence of letters.
-> This challenges the validity of the model because it is not certain that working memory operates this way in everyday situations.
55
What is meant by interference theory?
When two pieces of information disrupt each other
| -forgetting occurs in LTM because we can't get access to memories even though they are available
56
How do memories effect interference?
worse when memories are similar
- in Proactive interference, previously stored info makes new information difficult to store
- in Retroactive interference, new info overwrites previous memories which are similar
57
What are the two types of interference?
```
Proactive interference (PI)
Retroactive interference (RI)
```
58
What is meant by proactive interference?
PI occurs when an older memory disrupts a newer memory
- old interferes with new
- e.g. a teacher learns many names in the past & can't remember names of her current class
59
What is meant by retroactive interference?
new interferes with old
- happens when a newer memory disrupts an older memory
- e.g. a teacher learns many new names this year but can't remember the names of previous students.
60
What happened during McGeoch & McDonald 1931 study, the procedure?
ppt's were asked to learn a list of words to 100% accuracy
- then given new list to learn, new material varied in the degree to which it was similar to the old
- grp1, synonyms - same meanings to original
- grp2, antonyms - opposite meanings to original
- grp3, unrelated to original
- grp4, consonant syllables
- grp5, three-digit numbers
- grp6, no new list, ppt's rested - control group
61
What did McGeoch & McDonald 1931 find & conclude?
performance depending on the nature of the second list, the most similar material, synonyms, produced the worst recall
- this shows that interference is strongest when the memories are similar
- grp6 could recall average of 5.4 items
- grp1 could recall average of 1.2 items
62
A strength for interference theory, is support for interference in real-world situations.
Baddeley and Hitch 1977
asked rugby players to recall the names of teams they had played against during a rugby season. Players didn't play the same number of games, due to injuries.
-> This shows that interference operates in some everyday situations, increasing the validity of the theory.
63
A counterpoint for interference theory
interference in everyday situations is unusual because the necessary conditions are relatively rare. e.g. similarity of memories. Therefore most everyday forgetting may be better explained by other theories like retrieval failure.
64
A limit for interference theory, is that interference effects may be overcome using cues.
Tulving & Psotka 1971
gave ppt's lists of words organised into categories, they weren't told the categories. Recall of first list was 70% but fell with each new list, showing proactive interference. When given a cued recall test, knowing the names of categories, recall rose again to 70%.
-> this shows that interference causes just a temporary loss of access to material still in LTM - not predicted by theory.
65
A strength of interference theory, is support from drug studies.
Material learned just before taking diazepam recalled better than a placebo group one week later - this is retrograde facilitation. The drug stopped the new info reaching brain areas that process memories, so it could retroactively interfere with stored information.
-> This shows that the forgetting is due to interference, reducing the interference reduced the forgetting.
66
what is meant by the retrieval failure theory?
a lack of cues can cause retrieval failure
- when info is initially placed in memory , associated cues are stored at the same time
- if the cues aren't available at the time of retrieval, you might not access memories that are actually there
67
what is the encoding specificity principle, Tulving 1983?
cues help retrieval if the same ones are present both at encoding and at retrieval
if the cues available at encoding and retrieval are different there will be some forgetting
68
What are the links between encoded cues and material to be remembered?
meaningful links - the cue STM leads you to recall lots of material about short-term memory
-not meaningful links: Context-dependant forgetting and state-dependent forgetting
69
What is meant by context-dependant forgetting?
recall depends on external cue
e.g. weather or a place
linked meaningfully to information
godden & baddeley 1975
70
What is meant by state-dependent forgetting?
recall depends on internal cue
linked to mental state
e.g. Feeling upset & being drunk
Carter & Cassaday 1998
71
What was Godden & Baddeley's 1975 procedure?
deep sea divers learned word lists and were later asked to recall hem
- condition1, learn on land - recall on land
- condition2, learn on land - recall underwater
- condition3, learn underwater - recall on land
- condition4, learn underwater - recall underwater
72
What did Godden & Baddeley 1975 find and conclude?
accurate recall was 40% lower in conditions 2 & 3, the mismatched contexts, than in condition 1&4, the matched contexts
-retrieval failure was due to absence of encoded context cues at the time of recall, material was not accesible
73
What was the Carter & Cassaday 1998 procedure?
ppt's learned lists of words and later recalled them
- con 1, learn on drug - recall on drug
- con 2, learn on drug - recall not on drug
- con 3, learn when not on drug - recall on drug
- con 4, learn not on drug - recall not on drug
74
What did Carter & Cassaday 1998 find and conclude?
recall was significantly worse in conditions 2 & 3, the mismatched cues, compared with conditions 1 & 4, the matched cues.
-when the cues at encoding are absent at retrieval than more forgetting occurs
75
A strength of retrieval failure is that retrieval cues have real-world application.
People often go to another room to get an item but forget what they wanted, but they remember again when they go back into the original room. When we have trouble remembering something, it is probably worth making the effort to recall the environment in which you learned it first.
-> This shows how research can remind us of strategies we use in real world to improve our recall.
76
A strength of retrieval failure is the impressive range of supporting evidence.
For example, Godden & Baddeley, and carter and Cassady show that lack of cues at recall leads to everyday forgetting. In fact, Eysenck & Keane 2010 argue that retrieval failure is perhaps the main reason for forgetting in LTM.
->This evidence shows that retrieval failure due to a lack of cues occurs in everyday life as well as in highly-controlled labs.
77
A counterpoint to strength of retrieval failure is impressive range.
Baddeley 1997
argues that different contexts have to be very different indeed before an effect is seen. Learning something in one room and recalling it in another is unlikely to result in much forgetting because the environments are not different enough.
This means that retrieval failure due to lack of contextual cues may not explain much everyday forgetting.
78
A limitation for retrieval failure is that context effects vary in recall and recognition.
Godden & Baddeley 1980 replicated their underwater experiment using a recognition test instead of recall. There was no context-dependant effect. Findings were the same in all four conditions whether the contexts for learning and recall matched or not.
-> This suggests that retrieval failure is a limited explanation for forgetting because it only applies when a person has to recall information rather than recognise it.
79
eval extra for retrieval failure, the problems with the ESP.
Retrieval failure theory is supported by research showing that forgetting occurs when there is a mismatch of cues - the encoding specificity principle. However, we can't independently establish whether a cue has really been encoded or not, so the argument for the role of cues is circular.
-> therefore the ESP specifically is not scientifically testable, so we can't be certain that forgetting is due to retrieval failure.
80
why do leading questions effect EWT?
response bias explanation
-wording of a question has no enduring effect on an eyewitnesses' memory of an event, but influences the kind of answer given
substitution explanation
-wording of a question does affect eyewitness memory, it interferes with the original memory, distorting it's accuracy.
81
why does post-event information affect EWT?
memory contamination
-when co-witnesses discuss a crime, they mix information from other witnesses with their own memories.
memory conformity
-witnesses go along with each other to win a social approval or because they believe that other witnesses are right
82
what does the misleading info explanation of eyewitness testimony include?
Leading questions
Post-event info
Loftus & Palmer
Gabbert
83
what is meant by conformity theory in EWT, misleading info?
when eyewitnesses go along with other witness testimonies
84
what is meant by source confusion in EWT?
distorts original memories because witnesses confuse what they actually saw with what they subsequently heard
85
What is meant by post-event discussion?
when co-witnesses talk about the event with each other, this can contaminate eyewitness testimony.
86
what is meant by leading questions?
point to a certain answer because of how they are phrased
87
What was Loftus & Palmers 1974 procedure for leading questions study?
45 students watched film clips of car accidents and then answered questions about speed.
The critical question = 'about how fast were the cars going when they hit each other?'
-5 groups of 9 ppt's, each grp given a different verb in the critical question: hit, contacted, bumped, collided or smashed.
88
What did Loftus & Palmer 1974 find?
the verb 'contacted' produced a mean estimate speed of 31.8mph
the verb 'smashed', the mean was 40.5 mph
-the leading questions biased eyewitness recall of an event, the verb smashed suggested a faster speed of the car than 'contacted'
89
What was the procedure of Gabbert's 2003 post-event discussion study?
paired ppt's watched a video of the same crime but filmed so each ppt could see elements in the event that the other could not
-both ppt's discussed what they had seen on the video before individually completing a test of recall.
90
What did Gabbert 2003 find?
71% of ppt's wrongly recalled aspects of the event they did not see in the video but had heard in the discussion
-in the control group, there were no discussion & no subsequent errors
this shows evidence for memory conformity
91
A strength of misleading information is real-world application in the criminal justice system.
The consequences of inaccurate EWT are serious. Loftus 1975 argues police officers should be careful in phrasing questions to witnesses because of distorting effects. Psychologists are sometimes expert witnesses in trials and explains limits of EWT to juries.
-> Therefore psychologists can improve how the legal system works and protect the innocent from faulty convictions based on unreliable EWT.
92
A counterpoint of strength for misleading info real world application
Loftus and Palmer showed film clips - a different experience from a real event. ppt's are also less concerned about the effect of their responses in a lab study. Therefore researchers may be too pessimistic about the effects of misleading information, EWT may be more reliable than studies suggest.
93
A limit for misleading info is the substitution explanation is evidence challenging it.
Sutherland & Hayne 2001
found their ppt's recalled central details of an event better than peripheral ones, even when asked misleading questions. This is presumably because their attention was focused on the central features and these memories were relatively resistant to misleading information.
-> Therefore the original memory of an event survived and was not distorted, which is not predicted by the substitution explanation.
94
A limit for misleading info is that evidence doesn't support memory conformity.
Skagerberg and Wright 2008
ppt's discussed film clips they had seen in one version the mugger had dark brown hair and the other light brown. The ppt's recalled a 'blend' of what they had seen and what they heard from their co-witnesses, rather than one or another e.g. said hair was 'medium brown'.
->this suggest that memory itself is distorted through contamination by post-event discussion and is not the result of memory conformity.
95
What is anxiety?
a sense of unease or worry
96
What is meant by the Yerkes-Dodson 1908 law?
the inverted-U theory states that performance will increase with stress but only to a certain point, when it decreases drastically
the relationship between performance and arousal/stress is an inverted u
97
what is meant by the weapons effect/focus?
when a crime involves a weapon, this creates anxiety
- a witnesses' attention is then focused on the weapon living less attention for other details of the event
- can reduce the accuracy of EWT
98
What was Johnson & Scott 1978 procedure?
ppt's sat in a waiting room believing they were going to take part in a lab study
- low anxiety condition, ppt's heard a casual conversation & then saw a man walking through the waiting room carrying a pen with grease on his hands
- high anxiety condition, a heated arguement was heard, accompanied by breaking glass, a man than walked through the room holding a knife covered in blood
- then asked to pick the man from a set of 50 photographs.
99
What did Johnson & Scott find & conclude?
49% of ppt's in the low anxiety condition and 33% of high anxiety ppt's were able to identify the man
-the tunnel theory of memory argues that people have enhanced memory for central events, weapon focus as a result of anxiety has this effect
100
What was Yuille & Cutshall 1986 procedure?
anxiety has a positive effect
- in an actual crime a gun-shop owner shot a thief dead, there were 21 witnesses.
- 13 agreed to ppt in study
- PPT's were interviewed 4-5 months after the incident, the info recalled was compared to the police interviews at the time of the shooting.
- witnesses rated how stressed they felt at the time of the incident
101
What did Yuille & Cutshall 1986 find and conclude?
Witnesses were very accurate in what they recalled and there was little change after 5 months
some details were less accurate e.g. age, height & weight
-ppt's who reported highest levels of stress were most accurate - 88% accurate.
-Anxiety does not appear to reduce the accuracy of EWT for a real-world event and may even enhance it.
102
explaining the contradictory anxiety findings:
Inverted U theory
| Affects memory -
103
what is meant by affects memory in Anxiety?
deffenbacher 1983
reviewed 21 studies of EWT with contradictory findings on the effects of anxiety on recall
-he suggested the Yerkes-Dodson effect could explain this - both low & high anxiety levels produce poor recall, whereas optimum levels can lead to very good recall
104
A limit for EWT Anxiety is that anxiety may not be relevant to weapon focus.
Johnson & Scott 1978
participants may have focused on the weapon not because they were anxious but because they were suprised. Pickel 1998 found that accuracy in identifying the 'criminal' was poorest when the object was in their hand was unexpected e.g. raw chicken and a gun in a hairdressers.
-> this suggests the weapons effect is due to unusualness rather than anxiety/threat so tells us nothing about the specific effects of anxiety on recall
105
A strength for EWT anxiety is supporting evidence for the negative effects.
Valentine & Mesout 2009
Used heart rate to divide visitors to the London Dungeon's labyrinth into low and high anxiety groups. High-anxiety ppt's were less accurate than low anxiety describing and identifying a person. This supports the claim that anxiety has a negative effect on immediate eyewitness recall of a stressful event.
106
A strength for EWT anxiety is supporting evidence for positive effects
Christianson & Hubinette 1993
interviewed actual witnesses to bank robberies - some were direct victims, high anxiety, and others were bystanders, low anxiety. They found more than 75% more recall across all witnesses. Direct victims were even more accurate.
-> This suggests that anxiety does not affect the accuracy of eyewitness recall and may even enhance it.
107
EWT the cognitive interview what is it based on?
psychological understanding of memory
- Fisher & Geiselman 1992 claimed that EWT could be improved if the police use techniques based on psychological insights into how memory works
- they called it the cognitive interview, indicates it's foundation in cognitive psychology
- Rapport is established with interviewee using four main techniques.
108
What does the cognitive interview consist of?
1. Report everything
2. Reinstate the context
3. Reverse the order
4. Change perspective
109
what does report everything consist of?
witnesses are encouraged to include every detail of an event, even if it seems irrelevant or the witness is not confident about it
-trivial details could be important and may trigger other memories.
110
What does reinstate the context mean?
the witness returns to the original crime scene in their mind & imagines the environment and their emotions.
-based on concept of context-dependent forgetting, cues from context may trigger recall.
111
What does reverse the order mean?
events are recalled in a different order e.g. from end to middle
- prevents people basing their descriptions on their expectations of how the event must have happened rather than the actual events.
- prevents further dishonesty, as it is harder to produce an untruthful account.
112
what does change perspective mean?
Witnesses recall the incident from other people's perspectives.
How would it have appeared to another witness or to the perpretrator?
-prevents the influence of expectations and schemo on recall, schema = packages of info developed through experience, generate a framework for interpreting incoming information.
113
what is the enhanced cognitive interview?
Fisher 1987 developed additional elements of the cognitive interview.
- includes a focus on the social dynamics of the interaction e.g. knowing when to establish & relinquish eye contact.
- also includes details such as reducing the eyewitnesses anxiety, minimising distractions, getting the witness to speak slowly and asking open ended questions.
114
A strength of the cognitive interview is research support for the effectiveness of the CI.
A meta analysis by Kohnken 1999
combined data from 55 studies comparing cognitive interview with the standard police interview. The CI produced an average of 41% more correct information than the standard interview. only four studies showed no difference. This shows us that CI is effective in helping witnesses recall information that is available but no accesible.
115
A counterpoint for strength of cognitive interview
Kohnken also found increases in the amount of inaccurate information, especially in the ECI,
Therefore police officers need to be very careful about how they treat eyewitness evidence from CIs/ECIs
116
A limit for cognitive interview is that some elements of the CI are more useful than others.
Milne & Bull 2002
found that each individual technique of CI alone produced more information than the standard police interview.
But they also found that combining report everything & reinstate the context produced better recall than any other technique individually or combined.
->This casts doubt on the credibility of the overall CI because some of the techniques are less effective than others.
117
A limit for cognitive interview is the the CI is time-consuming.
Police are reluctant to use the CI because it takes more time than the standard police interview e.g. to establish rapport and allow the witness to relax. The CI also requires special training but many forces don't have the resources to provide more than a few hours' training.
-> This suggests that the complete CI is not realistic for police officers to use and it might be better to focus on just a few key elements.
