Paper 1 - Memory Flashcards
Key study in coding in STM and LTM
Baddeley
Procedure of Baddeley’s study
4 groups given different lists to remember (acoustically/semantically similar/dissimilar)
Tester STM and LTM- participants asked to recall the words in the correct order. Some participants were required to recall words immediately and others had to wait for 20 minutes.
Findings and conclusions of Baddeleys study
Acoustically similar words remembered worst for STM, semantic for LTM.
Suggests that information is coded acoustically in STM and semantically in LTM
Limitation of Baddeleys study
Artificial stimuli rather than meaningful material.
The words used in the study had no meaning to the participants.
This means we should be cautious about generalising the findings to different kinds of memory task.
E.g when processing more meaningful info, people may use semantic encoding even in STM
Key study for the capacity of STM
Jacobs
Procedures of Jacobs study
Developed digit span technique - refers to digits/letters being read one at a time.
Researcher gives for example, four digits and then the participant is asked to recall these in the correct order. It this is correct, the researcher reads out five digits and so on until the participant cannot recall the order correctly - this determines the individuals digit span.
Findings of Jacobs study
Mean span for digits was 9.3.
Mean span for letters was 7.3
Limitation of Jacobs study
One limitation of this study is that it was conducted a long time ago.
Early resech often lacked adequate control of extraneous variables.
For example participants may have been distracted while they were being tested so they didn’t perform as well as they might.
This would mean the results may not be valid because there were confounding variables that were not controlled.
Procedure of Millers study
A review of other research on memory which tested the amount of information we receive, process and remember in our immediate memory.
He observed everyday practice and noted that things come in sevens: 7 days of the week, deadly sins etc
Findings of Millers study
Suggests capacity of STM is about 7 items (+/- 2)
Chunking is used to increase capacity - grouping sets of digits or letters into meaningful units or chunk
What is capacity
The amount of information that can be held in a memory store
Limitation of Millers study
He may have overestimated the capacity of STM.
COWAN reviewed other research and concluded that the capacity of STM was only about 4 chunks.
Suggests the lower end of Millers estimate is more appropriate than 7 items.
Key study into the duration of STM
Peterson and Peterson
Procedure of Peterson and Peterson’s study
24 undergraduate students were given a consonant syllable (also called trigrams) to remember and a 3-digit number.
Student asked to count back from that number until told to stop.
Counting backwards prevented any rehearsal of the consonant syllable (this would increase the students memory).
Each trial they were told to stop after different times. This is called the Retention intervals of 3,6,9,12,15 or 18.
Findings of Peterson and Peterson’s Study
After 3 seconds recall was about 80%.
Recall after 18 seconds was about 3%.
Suggests that STM May have a very short duration indeed, unless we repeat something over and over again (e.g maintainable rehearsal)
Limitation of the Peterson and Peterson study
Stimulus material was artificial.
Trying to memorise consonant syllables does not reflect most real-life memory activities where what we are trying to remember is meaningful.
Might say the study lacked ecological validity.
We do sometimes try to remember fairly meaningless things like phone numbers so it’s not totally irrelevant
Key study of duration to LTM
Bahricks
Procedure of Bahricks study
Nearly 400 participants from America aged 17-74.
Yearbooks obtained from the participants or directly from the schools. Recall tested in various ways:
a photo recognition test consisting of 50 photos, some photos were from the participants high school yearbook.
A free recall test where participants were asked to list all the names they could remember of individuals in their graduating class.
Findings of Bahricks study
Face recognition after 48 years of graduation was 90%
Free recall was less good. After 15 years, this was about 60% accurate, dropping to 30% after 48 years.
Suggests that the study suggests that long-term meteorites can last a very long time indeed, but may need cues in order to be accessed.
Limitation of Bahricks study
Rehearsal may explain the results.
Some participants might have looked at the yearbooks regularly and that’s why their recognition/recall was so good.
In this case rehearsal is acting as an extraneous variable.
This means that some results may not be due to LTM
Strength of Bahricks study
High external validity.
Real-life meaningful memories were studied.
When lab studies were done with meaningless picture to be remembered, recall rates were lower (SHEPHARD).
Downside is that confounding variables are not controlled.
What is coding
The format in which information is stored in the various memory stores
What is a consonant syllable
Three letter chunks with no vowel, also called a trigram
What is duration
The length of time information can be held in memory
What is the LTM
The permanent memory store. Coding is mainly semantic. It has unlimited capacity and can store memories for up to a lifetime
What is a memory trace
The physical record or ‘trace’ of a memory
What is rehearsal
Repeating information over and over again in order to retain that information in memory
What is the STM
The limited-capacity memory store. Coding is mainly acoustic; capacity is between 5 and 9 items on average, duration is between 18 and 30 seconds
What is spontaneous decay
The disappearance of the physical memory trace over time, where there is no external cause
Who created the multi-store model of memory
Atkinson and Shiffrin
What is acoustic
Refers to the sounds or the sense of hearing
What is amnesia
A loss of memory due to brain damage, disease or psychological trauma
What is echoic memory
The sensory register that stores auditory information
What is elaborative rehearsal
The deep semantic processing of to-be-remembered information by thinking about its meaning and linking information to existing knowledge. This is in constant to maintainence/verbal rehearsal, which involves simple rote repition
What is iconic memory
The sensory register that stores visual information
What is the MSM
A representation of how memory works in terms of three stores called sensory register, short term memory and long term memory. It also describes how information is transferred from one store to another, how it is remembered and how it is forgotten
What is sensory memory
Memory store for each of our five senses, such as vision (iconic) and hearing (echoic). Coding in the iconic sensory register is visual and in the echoic sensory register it is acoustic. The capacity of sensory register is huge and information lasts for a very short time
What are the stores in the MSM linked by
Processing such as attention and maintenance rehearsal
Characteristics of the sensory register in MSM
Stimulus from environment will pass into the sensory registers. This part of memory is not one store but several, one for each 5 senses.
Material in the sensory register last very briefly, the duration is less than half a second.
High capacity, over one hundred million cells in one eye.
Coding is related to each sense e.g visual for eyes.
What causes items in the sensory register to transfer to STM
Paying attention to them
Characteristics of the STM in MSM
Limited capacity store - it can only contain a certain number of stuff before forgetting takes place.
Information in STM is coded acoustically.
Duration of STM is about 30 seconds unless info is rehearsed
What does maintenance rehearsal do
Helps to transfer information from STM to LTM as long as we rehearse it long eneough
Characteristics of LTM in MSM
Potential unlimited in terms of capacity and can last for many years.
Potential unlimited in terms of duration.
Coding tends to be in terms of meaning I.e semantic.
Although material is stored in the LTM when we want to recall it has to be transferred back to STM by process called retrieval
What is retrieval
Recall of information previously stored in memory
Strength of MSM of memory
Supported by research showing STM and LTM are different.
Baddeley found we mix up words that sound similar when we use our STMS but we tend to mix up words that are semantic using our LTMS.
Clearly shows that coding is different in each store.
Supports the MSM view that these two mentors stored are separate and independent.
3 limitations of the MSM of memory
Evidence suggests there’s more than one type of STM. patient KF. KFs short term memory for digits was very poor when they read them out loud to him but his recall was much better when he was able to read the digits himself. MSM states the STM is a unitary store however the case of KF suggest that there must be one short-term store to process visual information and one short-term store to process auditory information. Working memory model is better able to account for the care of KF.
Oversimplifies LTM. Lots of evidence that LTM is not a unitary store. E.g we have one long-term memory store for our memories of facts and one for memories of how to ride a bicycle. MSM does not reflect that these different types of LTM which is a problem.
Only includes one type of rehearsal. There are two types: maintenance as described in the MSM, but this does not transfer information into the LTM. Elaborative rehearsal is needed for long term storage. This occurs when you link information to your existing knowledge, or you think about what it means. Very serious limitation of the MSM because it is another research finding that cannot be explained by the model.
What are the 3 types of long term memory
Episodic memory
Semantic memory
Procedural memory
What are episodic memories
A long term memory store for personal events. It includes memories of when the events occurred and of the people, objects, places and behaviours involved. Memories from this store have to be retrieved consciously and with effort
3 characteristics of episodic memories
They are time-stamped.
They involve several elements like people, places, objects and behaviours.
You have to make a conscious effort to recall them.
What are semantic memories
A long term memory store for our knowledge of the world. This includes facts and our knowledge of what words and concepts mean. These memories usually also need to be recalled deliberately
Why are semantic memories not time-stamped
It is less personal and more about the knowledge we all share
What are procedural memories
A long term memory store for our knowledge of how to do things. This includes our memories of learned skills. We usually recall these memories without making a conscious or deliberate effort
Example of recall occurring without great effort for procedural memories
Changing gear in the car without having to recall how to do so
Why are procedural skills hard to explain to someone
Because we can recall these memories without conscious awareness
Strength of episodic memory store
Case study evidence. In the case of HM and Clive Wearing, both men had great difficulty recalling events that had happened to them in their past as a conseqnce of amnesia. In contrast, semantic memories were relatively unaffected for example they understood the meaning of words. Supports the view that there are different memory stores in LTM because one store can be damaged but the others unaffected
Strength of different LTM stores
Brain scan studies provide evidence. TULVING got participants to perform various memory tasks while their brains were scanned using a PET scanner. Found episodic and semantic memories were recalled in the prefrontal cortex and the left side of the prefrontal cortex was involved in semantic and right prefrontal cortex was episodic. Supports the view that there is a physical reality to the different types of LTM.
2 limitations of different stores of LTM
Problems with clinical evidence. Cases like HM and Clive Wearing provide useful information about what happens when memory is damaged. However there is a serious lack of control of all sorts of different variables in clinical studies. E.g it’s not possible to control the precise location of the brain damage. Therefore it’s difficult to generalise from these case studies to determine the exact nature of LTM.
COHEN and SQUIRE argue that episodic and semantic are stored together in one LTM store they call declarative memory. It is important to get the distinction between semantic and episodic memories right because the way we define them will influence the way in which memory studies are conducted and memory is investigated
What is declarative memory
Memories that are consciously recalled, explicit and can be put into words
What is non-declarative memory
Memories are implicit, on automatic pilot and without conscious thought they cannot be put into words
How do PET scans work
Radioactive glucose is ingested and can be detected in the active areas of the brai
What is the prefrontal cortex
Section of the cerebral cortex at the front of the brain associated with planning complex cognitive behaviour, personality expression, decision making and moderating social behaviour
Who created the working memory model
Baddeley and Hitch
What is the working memory model
A representation of short-term memory. It suggest that STM is a dynamic processor of different types of information using sub-units coordinated by a central decision-making system
What parts of the mind is the WMM concerned about
The part of the mind that is active when working on an arithmetic problem or playing chess or comprehending language
What is the central executive in the WMM
The component of the WMM that co-ordinates the activities of the three subsystems in memory. It also allocates processing resources to those activities. It has very limited storage capacity or possibly none at all
What are the slave systems of the WMM
Phonological loop
Visuo-spatial sketchpad
Episodic buffet (added in 2000)
What is the phonological loop in the WMM
The component of the WMM that processes information in terms of sound. This includes both written and spoken material. It’s divided into the phonological store and the articulatory process
What is the phonological store
Component of the phonological loop that stores the words you hear - ‘inner ear’
What is the articulatory process
A competent of the phonological loop which acts as an ‘inner voice’ I.e words/sounds are verbally repeated (maintenance rehearsal)
What is the Visuo-spatial sketchpad
The component of the WMM that processes visual and spatial information in a mental space we often call our ‘inner eye’
What did LOGIE subdivided the visuo-spatial sketchpad into
The visual cache, which stores visual data, and the inner scribe which records the arrangement of objects in the visual field
What is the episodic buffer
The competent of the WMM that brings together material from the other subsystems into a single memory rather than separate strands - this is done basically by recording events (episodes) that are happening. Provides a bridge between working memory and long-term memory
What illustrates the main feature of the WMM, that there is no interference when performing two different tasks
Dual-task performance
What is dual task performance
Refers to a research procedure where an individual is asked to perform two tasks simultaneously. If participants are slower doing these tasks at the same time than when doing it separately, it is assumed that both tasks compete for the same resources in the brain
Three strengths of the WMM
Support for a separate visual and acoustic store. Patient KF. He had poor STM ability for verbal information but could process visual information normally. Suggests that just his phonological loop had been damaged leaving other areas of memory intact. Supports the existence of a separate visual and acoustic store.
Word-length effect demonstrates support for the phonological loop. BADDELEY demonstrated that people find it more difficult to remember a list of long words rather than short words - the word-length effect. This is because there is a finite space for rehearsal in the articulatory process (probably about 2 seconds). The word length effect disappears if a person is given an articulatory suppression task, demonstrating the articulatory process at work.
Brain scanning have support WMM. Participants asked to do Tasks that involved the central executive while having a brain scan and found activity in the prefrontal cortex. Activity in this area increased as the tasks got harder. As demand on the CE increases, it has to work harder to fulfill its function. Provides evidence that the CE may have a physical reality in the brain.
Why may evidence from brain-damaged patients not be reliable
Because it concerns unique cases with patients who have had traumatic experiences
What is the word-length effect
People remember lists of short words better than lists of long words, governed by the capacity of the phonological loop
What is an articulatory suppression task
An activity which prevents rehearsal of words in the articulatory loop
Limitation of the WMM
Lack of clarity for the central executive. Cognitive psychologists suggest that this component is unsatisfactory and doesn’t really explain anything. It needs to be more clearly specified than just being simply ‘attention’. For example, some psychologists belive it may consist of separate components. This means the WMM hasn’t been fully explained
What are the two explanations for forgetting
Interference
Retrieval failure
What is interference
Forgetting because memory blocks another, causing one or both memories to be distorted or forgotten because we can’t access the information
What are the two types of interference
Proactive interferences
Retroactive interference
What is proactive interference
Forgetting occurs when older memories, already stored, disrupt the recall of newer memories. The degree of forgetting is greater when the memories are similar
Example of proactive interference
A teacher has learned so many names over the years that she has difficulty remembering the names of her current class
What is retroactive interference
Forgetting occurs when newer memories disrupt the recall of older memories already stored. The degree of forgetting is again greater when the memories are similar
Example of retroactive interference
Your teacher has learned so many new names this year that she has difficulty remembering the names of students last year
When is interference worse
When memories or learning is similar:
In proactive this could be because previously stored information makes new information difficult to store.
In retroactive it could be that new information overwrites precious memories which are similar
Key study in interference
McGeoch and McDonald
Procedure of McGeoch and McDonalds study
Participants given a list of 10 words to learn off by heart until they remember with 100% accuracy. Following this, participants given a new list to learn; material varied in similarly to the original material. 6 conditions: Group 1- synonyms Group 2- antonyms Group 3- words unrelated Group 4- nonsense syllables Group 5- three digit numbers Group 6- no new list
Findings of McGeoch and McDonalds study
Most similar material (synonyms) produced the worst recall. When participants were given very different material, like the numbers, the mean number of items recalled increased.
Conclusions of McGeoch and McDonalds study
Interference is strongest when the memories are similar. In group 1 it is likely that the words with the same meanings as the original list blocked access or that the new material became confused with the old material
What is a cued recall test
A method of testing memory where participants are given material to be learned, and when recall is tested, they are given cues to enhance recall. This permits one to discover all the words that are available not just those that are currently accessible
Two strengths of interference as an explanation for forgetting
Evidence from lab studies consistently demonstrate interference in memory. E.g McGeoch and McDonalds research on the effects of similarity. Most of these studies show that both types of interference are likely to cause forgetting from LTM. Strength bc lab experiments control the effects of and thus give us confidence that it’s a valid explanation.
Real life studies have support the interference explanation. BADDELEY AND HITCH asked rugby players to try and remember the names of the teams they had played so far, week by week. Results showed that accurate recall did not depend on how long ago the match took place but rather the number of games they had played in the mean time.
Two limitations of interference as an explanation for forgetting
Use of artificial materials. Stimulus material used in most studies are lists of words. This is quite some distance from things we remember in everyday life. For example, faces and birthdays etc. Limitation bc the use of artificial tasks makes interference much more likely in the lab but it may not be as likely outside the lab.
Time allowed between learning in the research. For practical reasons the time period between learning lists of words and recalling them is relatively short. For example, a participant may have to learn one list or words and then a second list after 20 minute. A problem because the research reduced the whole experience of learning into a very short time period and it is unlikely to reflect how we normally learn and remember information.
What is retrieval
Recall of information previously stored in memory
What can cause retrieval failure
When information is initially placed in memory , associated cues are stored in the same time. If these cues are not available at the time of recall, you might not be able to access memories that are actually there
What is the encoding specificity principle
A cue can help us recall information if the cue was present at encoding (coding when we learn the material) and at retrieval (when we are recalling it)
The closer the retrieval cue is to the original cue, the better the cue works
Who created the encoding specificity principle
TULVING
What are some cues linked to
The material-to-be remembered in a meaningful way. For example the cue ‘STM’ May lead you to recall all sorts of information about short-term memory
What is context dependent forgetting
When memory retrieval is dependant on an external/ environmental cue (e.g the weather) that was present at the time of learning. The external cues available are different from ones at recall which leads to retrieval failure
What is state-dependant forgetting
When memory retrieval is dependant on an internal cue - state of mind (e.g feeling upset, being drunk) that was present at the time of learning
Key study in Context-dependant forgetting
GODDEN AND BADDELEY
Procedure of the Godden and Baddeley study
Deep-sea divers learned a list of words either underwater or on land and were then asked to recall the words either underwater or on land.
Four conditions in which two of them the context was the same for learning and recall:
Learn on land; recall on land
Learn on land; recall underwater
Learn underwater; recall on land
Learn underwater; recall underwater
Findings of the Godden and Baddeley study
When the environmental contexts of learning and recall did not match (conditions 2 and 3) accurate recall was 40% lower than when they did match.
When the external cues available at learning were different from those at recall, this led to retrieval failure due to lack of cues
2 strengths of retrieval failure as an explanation for forgetting
Supporting evidence. Godden and Baddeleys research with deep-sea divers. The amount of supporting evidence increases the validity of the explanation. This is especially true when the evidence shows retrieval failure occurs in real-life situations as well as in the high-controlled conditions of the lab.
Useful real life application. People often report going upstairs, coming down to get an item, forgetting what it was and going upstairs again and then remembering! The application is when we have trouble remembering something it is probably worth revisiting the environment in which you first learned it. It is the basic principle of the cognitive interview.
2 limitations of retrieval failure as an explanation for forgetting
Issue with TULVINGS ESP is that it cannot be tested and leads to a form of circular reasoning. In experiences where a cue produces the successful recall of a word, we assume that a cue must have been present at the time of learning. If a cue does not result in successful recall of a word, then we assume that the cue was not encoded at the time of learning. But these are just assumptions and there’s no way to establish whether a cue has been encoded.
BADDELEY argues that context effects are not actually very strong in real life. Different contexts have to be very different before an effect is seen. E.g land and water are completely different environments. In contrast learning something in one room and recalling it in another is unlikely to result in much forgetting because the environments are generally not different enough. Limitation because it means that the real life applications of retrieval failure due to contextual cues don’t actually explain much forgetting
What are the two factors effecting eye witness testimony
Misleading information
Anxiety
What are mnemonic techniques
Methods used to aid memory of information, such as simple rhymes or letters to stand for each word to be remembered
What is eyewitness testimony (EWT)
The ability of people to remember the details of events, such as accidents and crimes, which they themselves have observed. Accurate of EWT can be affected by factors such as misleading information, leading questions and anxiety
What is a leading question
A question which, because of the way it is phrased, suggests a certain answer
What is misleading information
Incorrect information given to the eyewitness, usually after the event (hence often called post-event information). It can take many forms, such as leading questions and post-event discussion between co-witnesses
What is own age bias
The tendency to recognise or remember things more easily if they relate to your own age group
What is post-event discussion (PED)
Occurs when there is more than one witness to an event. Witnesses may discuss what they have seen with co-witnesses or with other people. This may influence the accuracy of each witnesses recall of the event
What does the response-bias explanation suggests
That the wording of the question has no real effect on the eyewitnesses memories of an event, but does influence how they decide to answer
What is the substitution explanation
Suggests the wording of the question does affect eyewitnesses actual memory of the event. The wording of the question may interfere with the original memory in some way which distorts the accuracy of the memory
Key study into leading questions
LOFTUS AND PALMER
Procedure of Loftus and Palmers study
45 American students watched film clips or car accidents and got given questions about the accident.
The critical question was ‘about how fast were the cars going when they hit each other?’
5 groups of participants, each given a different verb in the critical question (hit/contacted/bumped/collided/smashed)
Findings of the Loftus and Palmer study
Smashed produced the highest estimate with a mean of 40.5 mph.
Contacted resulted in the lowest estimate of a mean 31.8 mph
Conclusions of the Loftus and Palmer study
The leading question biased the eyewitness recall of an event. The verb ‘smashed’ suggested that the speed of the car was faster than the verb ‘contacted’ and the participants altered their responses accordingly
Strength of the Loftus and Palmer study
Real-life application. Nature of the resech has led to hugely important practical uses for police officers and investigators. This is important because the consequences of inaccurate EWT can be very serious. LOFTUS believed that leading questions can have such a distorting influence on memory that police officers need to be very careful about how they phrase their questions when interviewing eyewitnesses. The rsearch into EWT can improve the way the legal system works and psychologists can appear in court trials as expert witnesses
Limitation of LOFTUS AND PALMERS research
Artificial materials. watching films of car accidents is very different to experiencing one for real, mainly because it lacks the stress. There’s evidence that emotions have an influence on memory. YUILLE and CUTSHALL found that people who had witnessed a traumatic real armed robbery had very accurate recall after 4 months. Shows that EWT isn’t always inaccurate. Limitation because studies that use artificial tasks may tell us very little about how leading questions affect EWT in cases of real crimes or accidents.
Why may post-event discussion change what others recall
Their memories may become contaminated because they combine (mis)information from other witnesses with their own memories. For example, if one witnesses remembers 2 robbers, other witnesses may start imaging it also and it becomes incorporated in their memory
What may post-event discussion lead to
Memory conformity - when witnesses go along with each other to win social approval or because they believe the other witnesses are right or wrong. It is an example of compliance rather internalisation
Key study into post-event discussion
Gabbert et al
Procedure of Gaberts study
In pairs, the participants watched the same video of a crime but filmed form different points of view. This means that each participants could see elements in the event that others could not.
Both partners then discussed what they had seen on the video before individually completing a test of recall.
Findings of Gabberts study
71% of the participants mistakenly recalled aspects of the event that they did not see in the video but had picked up in the post-event discussion.
0% errors in a control group, where there was no discussion.
2 Limitations of EWT research
There may be individual differences in the accuracy of eyewitness testimonies. Evidence that older people are less accurate than younger people when giving eyewitness reports. However, age groups are more accurate when identifying people of their own age (own-age bias). Research often uses younger people as the target to identify which may mean that testimony appears less accurate than it really is.
Ecological validity of many EWT research studies. What you remember as an eyewitness can use some very important consequences in the real world, but the same is not true in research studies. The difference between the two may mean that EWT research does not reflect EWT accuracy in real life. E.g in the real world eyewitnesses May search their memory with greater effort because their testimony may lead to successful or wrongful conviction. In studies, participants may be more flippant. Argued that EWT accuracy is greater in the real world because of the seriousness with which eyewitnesses take their roles.
What is the key study into anxiety having a positive effect on EWT
Johnson and Scott
Procedure of Johnson and Scott’s study
One approach of studying anxiety is looking at weapon focus.
They led participants to believe they were going to take part in a lab study and were made to wait in a waiting room.
While sitting in the room participants heard an argument.
In low anxiety condition: a confederate walked through the waiting area carrying a greasy pen.
In high anxiety condition: the heated argument was followed by the sound of breaking glass. A confederate walked out of the room holding a paper knife covered in blood.
Findings of Johnson’s and Scott’s study
Participants had to pick out the confederate from 50 photos: 49% of the participants carrying a pen could identity him whereas only 33% of the knife condition could
What is the tunnel theory of memory
Argues that a witnesses attention narrows to focus on a weapon, because it is a source of danger and anxiety, supporting the weapon focus explanation
What is weapon focus
Witnesses attention is drawn to the weapon held by a criminal and therefore other details about a scenario are missed and not committed to memory
Key study into anxiety having a positive effect on EWT
Yuille and Cutshall
Procedure of Yuille and Cutshall study
Made use of a real-life crime that took place, invoking a real life shooting in Canada. The shop owner shot a thief dead. 21 witnesses, 13 agreed to take part in the study.
Interviews held 4-5 months after the incident and were compared to the original police interviews at the time.
Witnesses also asked to rate how stressed they had felt at the time, using a seven-point scale.
Findings of Yuille and Cutshall’s study
Witnesses were very accurate in their accounts and there was little change in the amount of accuracy after five months, though some details were less accurate such as colour of items and age/weight/height.participants who reported the highest level of stress were most actuate (about 88% compared to 75% of lead stressed group)
How can the contradictory finding of anxiety affecting EWT be explained
According to Yerkes and Dodson, the relationship between arousal and performance looks like an ‘inverted U’. It states that performance increases with stress, but only to a certain point, where it decreases dramatically:
What is the Yerkes Dodson Law
Refers to the relationship between performance and arousal. As arousal increases so does performance. However this only occurs up to a point; when arousal levels become too high, performance then begins to decrease
Who applied the Yerkes-Dodson law to EWT
DEFFENBACHER
How did DEFFENBACHER apply the Yerkes-Dodson law to EWT
Lower levels of anxiety produce lower levels of recall accuracy.
Accuracy increases with anxiety up to an optimal point.
A drastic decline in accuracy is seen when an eyewitness experiences more stress than the optimal point.
What is anxiety
A state of emotional and physical arousal. The emotions include having worried thoughts and feelings of tension. Physical changes include an increased heart rate and sweatiness. Anxiety is a normal reaction to stressful situations, but can affect the accuracy and detail of eyewitness testimony
Limitation of Johnson and Scott’s study
May test surprise rather than anxiety. The reason participants focus on the weapon may be because they are surprised at what they see rather than because they are scared. PICKELL conducted an experiment with scissors, handgun, wallet and raw chicken as hand-held items in a hair dressing salon. Eyewitness accuracy poorer in high conditions (chicken and handgun). Suggests that weapon focus effect is due to unusualness rather than anxiety and therefore tells us nothing specifically about the effects of anxiety on EWT
2 Limitations of research into anxiety’s affect on EWT
Ethical issues. Creating anxiety is very risky, potentially unethical because it may subject people to psychological harm purely for research. This is why real life studies are so beneficial. Psychologists interview people who have already witnessed a real-life event, so there is no need to create it. Issue doesn’t challenge the findings but it does question the need for the research.
Field studies lack control. Research usually interviews real life eyewitnesses sometimes after the event. All sorts of things may happen to the participants in the meantime that researchers can’t control. E.g post-event discussions. Limitation because it’s possible that these extraneous variables may be responsible for the accuracy of recall rather than anxiety, difficult to isolate the variables:
Limitation of the inverted-U explanation
Too simplistic. Anxiety is difficult to define and measure. One reason is because it has many elements: cognitive, behavioural, emotional and physical. The inverted-U assumes that one of these is linked to poor performance - physiological (physical) arousal. Therefore it fails to account for other factors. E.g the explanation states that arousal increases alterness but has nothing to say about how the emotional experience of eyewitnesses also affect the accuracy of memory
What is psychological harm
Emotional and/or mental damage such as reduced self-esteem or confidence
What is the cognitive interview
A method of interviewing eyewitnesses to help them retrieve more accurate memories. It uses four main techniques, all based on well-established psychological knowledge of human memory - report everything, reinstate the context, reverse the order and change perspective
What is the enhanced cognitive interview
Contains the same four retrieval rules as the original and additional aims to improve the social aspects of the interview, which further increases recall
Who created the cognitive interview and why
Fisher and Gieselman.
What did fisher and gieselman argue
They argued that EWT could be improved if the police used better techniques when interviewing witnesses. They suggested that such techniques should be based on psychological insights into how memory works, and called it the cognitive interview.
What is the first stage of the cognitive interview
The interviewer should aim to establish ‘rapport’ with the interviewee, so the interviewee feels the interviewer is not against them but will try to understand their feelings
What are the elements of the cognitive interview
Report everything
Context reinstatement
Reverse the order
Change perspective
What does the ‘report everything’ part of the cognitive interview consist of
Witnesses are encouraged to include every single detail of the event, even though it may seem irrelevant or the witnesses doesn’t feel confident about it. Seemingly trivial details may be important and, moreover, they may trigger other memories
What does the ‘context reinstatement ’ part of the cognitive interview consist of
The witness should return to the original crime scene ‘in their mind’ and imagine the environment and their emotions. This is based on context-dependant forgetting
What does the ‘reverse the order’ part of the cognitive interview consist of
Events should be recalled in a different chronological order, for example, from the final point back to the beginning, or from the middle to the beginning. This is done to prevent people using their expectations of how the event must have happened rather than the actual events. It also prevents dishonestly (harder for people to produce an untruthful account if they have to reverse it)
What does the ‘change perspective’ part of the cognitive interview consist of
Witnesses should recall the incident from other people’s perspectives. For example, how it would have appeared to other witnesses or the perpetrator
Who developed the enhanced cognitive interview
FISHER
What does the enhanced cognitive interview focus on
The social dynamics of the interaction e.g knowing when to establish and when to relinquish eye contact.
What ideas does the enhanced cognitive interview include
Reducing the eyewitnesses anxiety, minimising distractions, getting the witness to speak slowly and asking open-ended questions
3 limitations of the cognitive interview
Time-consuming. Police are reluctant to use the method because it takes more time than a standard police interview e.g more time is needed to establish rapport with the witness to allow them to relax. It also requires special training and many forces can’t provide more than a few hours. Means that it’s unlikely the ‘proper’ version of the CI is actually used (which may explain why police have not been that impressed by it).
Some elements may be more valuable than others. MILNE and BULL found that using a combination of ‘report everything’ and ‘context reinstatement’ produced better recall than any of the other conditions individually. Suggests that at least two elements should be used to improve police interviewing of eyewitnesses even if the full CI isn’t used.
Increase in inaccurate information (false positives). One study found an 81% it correct information but also a 61% increase of incorrect information when the enhanced CI was compared to a standard interview. Clear that the increase in correct information implies that police should continue to use CI however the results also suggest that police need to treat all information collected with caution.
Strength of the enhanced cognitive interview
Considerable support for the enhanced CI effectiveness. A meta-analysis combined data from 50 studies. The enhanced CI consistently provided more correct information than the standard interview used by police. Strength because studies indicate that there are real practical benefits to the police or using the enhanced version of the CI.
