Handout 2 - Memory

Memory

Eyewitness testimony - Cognitive interview

What is the Cognitive interview?

•This is a police technique which encourages witnesses to recreate the original context using four structured stages in order to increase access to stored memories of an event.

•A memory of an incident can be quite fragmented, therefore several retrieval strategies can be used in order to piece together information and make the picture as complete as possible.

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Cognitive interview techniques: Instructions

1.Context reinstatement (CR) = Mentally recreate how you were feeling and what was happening before, during and after the incident .

2. Report everything (RE) = Report every detail about the event even if it seems irrelevant or trivial

3. Recall from a changed perspective (CP) = Describe the event as it would have been seen from a different witness’ viewpoint

4. Recall in reverse order (RO) = Describe the event starting with the last thing you remember and work backwards

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Cognitive interview techniques: Why they work

1.Context reinstatement (CR) = Recalling feelings what was happening can act as state/context-dependent retrieval cues to access other memories

2. Report everything (RE) = Unrestrained recall may retrieval of details which might otherwise be inadvertently

3. Recall from a changed perspective (CP) = Information that has been observed can be retrieved through a variety of different ‘routes’

4. Recall in reverse order (RO) = Prevents use of schemas of what might have happened and makes the witness think about what actually happened

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Cognitive interview Evaluation: Strengths

+A combination of techniques works best:    

 Evidence has shown that a combination of techniques may be more valuable than using them in isolation. Milne and Bull (2002) found that each individual element was equally valuable. Each technique used singly produced more information than the standard police interview. However, they found that a combination of report everything and cognitive reinstatement produced better recall than any of the other conditions. This is a strength as it suggests that these two elements should be used to improve police interviewing of eye-witnesses, even if the full CI isn’t used.

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Cognitive interview Evaluation: Strengths

+Research to support the effectiveness of the cognitive interview:  Geiselman et al. (1985) showed participants police training videos of simulated violent crimes. 48 hours later they were interviewed about the films by an experienced Los Angeles police officer using cognitive interview, a standard police interview or an interview using hypnosis. Geiselman et al. found that the cognitive interview elicited the most accurate recall, followed by hypnosis and then the standard interview. This is a strength because it clearly demonstrates how CI can be used to enhance recalland demonstrates that it is more effective than other techniques including the standard interview.

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Cognitive interview Evaluation: Limitations

−Time consuming

Police may be reluctant to use CI because it takes more time (therefore greater cost) than standard police interview. For example, more time is needed to establish rapport with a witness and allow them to relax. The CI also requires special training and many police forces have not been able to provide more than a few hours of training. This is a problem as it means that many police forces may not carry out a complete CI, although it appears to be the best method to use to gain accurate EWT, alternative less effective methods are employed. This demonstrates how the practical application of psychology can be affected by the economy.

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Cognitive interview Evaluation: Limitations

−Creates an increase in inaccurate information:

 The techniques of CI aim to increase the amount of correct information, but the recall of incorrect information may also be increased. Kohnken et al. (1999) found an 81% increase of correct information but also a 61% increase of incorrect information when compared to a standard police interview. This is a problem because it questions the accuracy of procedure collecting in eye-witness testimonies.

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Comparison to standard interview

Standard Interview:

-Free Recall

-Possible Leading Questions

- Possible Less Accurate Information  Produced

-Easier & Less Time

-Cold Answers

 

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Whereas 

Cognitive Interview:             

-Clear order for Interviewee To Build A Picture          

-Less Susceptible To Leading Questions

-More Forensically Rich Detail

 -Extended Training & Lengthy Process

 -Answers in Context

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Eyewitness testimony

EWT recall may be affected during initial coding of the information. This means the emotional state caused by anxiety may negatively affect how we actually stored and encoded the information therefore affecting how accurately we can recall the correct information.

 

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Effect of anxiety on the accuracy of EWT 

•Factors occurring during an incident may affect how accurately information is later recalled.

•For example, a weapon focus effect may draw the attention of an eyewitness away from other aspects of the scene.

•An anxious emotional state may negatively affect how accurately information is initially encoded.

•This affects the accuracy of the information that is consequently stored and later recalled.

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Anxiety and EWT 

•The results of research into the effect of anxiety on EWT have been highly mixed.

•It is believed that eye witness testimony is most accurate when the anxiety level is somewhere in between low and high.

•High Anxiety = Bad recall

•Medium Anxiety = Best recall

•Low Anxiety = Poor recall

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LOFTUS ET AL (1987)

AIM:To investigate whether high levels of anxiety will affect accuracy of recall.

PROCEDURE: Loftus et al (1987) used two experimental conditions, one with a weapon and one without. The participants were asked to sit outside a room where they thought they heard a genuine discussion between two people.  

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PROCEDURE:

Low anxiety (no weapon) – the conversation was peaceful about some office equipment. When they finished a man emerged holding a pen and with grease on his hands.

High anxiety (with weapon) – The conversation was more heated, participants heard breaking glass and a man emerged holding a knife covered in blood.

All participants were then asked to identify the man from 50 photographs.

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•FINDINGS:

•Loftus found that in the low anxiety (no weapon condition), 49% of participants were able to accurately identify the man holding a pen from the photographs.

•In the high anxiety (with weapon) condition, memory recall was much less as there was only 33% accuracy from participants.

CONCLUSIONS:

•This suggests the weapon may have distracted attention from the person holding it.

•This therefore might explain why eyewitnesses sometimes have poor recall for certain details of violent crimes involving weapons as anxiety may be heightened.

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LOFTUS AND BURNS 

•PROCEDURE:

In another controlled study by Loftus and Burns, participants watched a film of a simulated robbery.

Some watched a non-violent version of the robbery and some watched a violent version (where a boy was shot in the face).

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FINDINGS:

When questioned afterwards those who watched the non-violent condition recalled significantly more details of the crime than those who watched the violent condition.

•CONCLUSIONS:

It seems that the shock of the event had heightened arousal and therefore disrupted memory storage of the details before and after the violent condition.

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Effect of anxiety on the accuracy of EWT
Evaluation: Strengths

+Reliability:

P: One strength of Loftus’ research is that her research groups have conducted several studies into EWT and have regularly found similar results.

E: Loftus tended to use a range of controlled experiments illustrating different examples of EWT.

E: By using a controlled environment Loftus could control extraneous variables, use identical procedures and make the procedure easy to replicate.

E: Loftus’ large number of studies into EWT have invariably found this same outcome – that anxiety negatively affects EWT.

R:This is a strength as it suggests that the findings from research into EWT and anxiety is reliable.

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Effect of anxiety on the accuracy of EWT 

 Evaluation: Limitations = Lacks ecological validity: 

−P: Loftus’ research has often been criticised for being artificial i.e. using a video of a robbery is not the same as a real incident.

−E: It is difficult to reproduce real life EWT conditions in a laboratory for various practical and ethical reasons i.e. it is not as unexpected or emotional as it would be in real life.

−E: Real life events often take place unexpectedly and in an atmosphere of high tension. They may be recalled significantly different to laboratory settings.

−E: Foster et al. (1994) found that if participants thought they were watching a real life robbery important to a real trial their identification of the robber was much more accurate than if they did not.

−R: Therefore controlled research settings such as Loftus’ may lack validity (both experimental and ecological) which in turn may undermine the findings.

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Effect of anxiety on the accuracy of EWT
Evaluation: Limitations

Lacks real life application:

P: However Loftus’ research has been criticised as it does not reflect real life EWT.

E: Christianson and Hubinette conducted anatural experiment which found that emotional arousal may actually enhance the accuracy of memory.

E: They questioned 110 real witnesses to 22 real bank robberies. They found that witnesses who had been threatened in some way were much more accurate in their recall of details, than those who had been onlookers and less emotionally aroused.

E:They concluded that people (especially victims) are good at remembering highly stressful events in real life rather than artificial surroundings.

R: This questions the ecological validity of Loftus’ research.

 

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Effect of anxiety on the accuracy of EWT
Evaluation: Limitations

−Ethical Issues:

−Psychologists cannot induce unnecessary psychological harm in their research and must gain informed consent from participants to take part. However with EWT one important variable is ANXIETY, unless this occurs naturally it is likely that the methods used to do this (such as using a violent film) may still cause mild harm, especially to children. This means that ethically, much research into this area may be questionable.

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Why is looking at the accuracy of EWT important? 

•82% of suspects chosen from an identification parade were convicted

74% of cases where eyewitness testimony was the only evidence were judged guilty.

•Studies of wrongful arrests show that eyewitness testimony is less accurate than people might expect.

Haff (87) studied 500 wrongful arrests and found 60% were due to eyewitness testimony.

•Ratner ran a similar investigation. Of the 205 mistaken arrests, more than 50% were due to witness testimony

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Eyewitness testimony

•Eyewitness Testimony (EWT) is the evidence provided in court by a person who has witnessed a crime/incident with a view to identifying the perpetrator of the crime.

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Factors affecting the accuracy of eyewitness testimony

Misleading information

•Leading Questions: the form or content of the question suggests to the witness what answer is desired or leads them to a desired answer, e.g. “What colour was the man’s hat?” is a leading question as it suggests the person is male and he WAS wearing a hat.

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LOFTUS AND PALMER (1974)

AIM: To investigate the effect of leading questions in distorting the accuracy of EWT.

PROCEDURE: They carried out a laboratory experiment using independent groups design.

45 American students were shown seven films of different car accidents. After each film the participants were given a questionnaire asking them to describe the accident, they were also asked a series of specific questions including one critical question.

•‘About how fast were the cars going when  they ____ each other?’

•The participants were divided into five groups and each group was asked the critical question with one of the following five verbs:

HIT , SMASHED, COLLIDED, BUMPED, CONTACTED

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LOFTUS AND PALMER (1974)

The IV = wording of the question (verb used)

The DV = speed reported by participants

Findings

The estimated speed was affected by the verb used.

The group given the word ‘smashed’ estimated the highest speed (40.8 mph) and the group given the word ‘contacted’ estimated the lowest speed (31.8 mph).

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LOFTUS AND PALMER (1974)

•CONCLUSIONS:

•The questions asked can be termed ‘Leading’ because they have affected the participant’s memory for the event.

•It can be concluded that language can have a distorting effect on EWT. This can lead to inaccurate accounts of the witnessed event.

•It is possible that the original memory has been reconstructed, but this is impossible to conclude with confidence as the original memory may have been replaced or experienced interference.This has important implications for the questions used in police interviews of eyewitnesses.

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Factors affecting the accuracy of eyewitness testimony

Misleading information

Post-Event Discussion: any information discussed after the event which could influence a witness’ memory of the event, e.g. discussions with other witnesses, news reports, chats with friends/family, etc.

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Gabbert et al (2003)

AIM = Gabbert et al. (2003) investigated the effect of post-event discussion on the accuracy of eyewitness testimony

PROCEDURE : 

Her sample consisted of 60 students from the University of Aberdeen and 60 older adults recruited from a local community.

Participants watched a video of a girl stealing money from a wallet. The participants were either tested individually (control group) or in pairs (co-witness group). The participants in the co-witness group were told that they had watched the same video, however they had in fact seen different perspectives of the same crime and only one person had actually witnessed the girl stealing. Participants in the co-witness group discussed the crime together. All of the participants then completed a questionnaire, testing their memory of the event.

 

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Gabbert et al (2003)

Findings:

Gabbert et al. found that 71% of the witnesses in the co-witness group recalled information they had not actually seen and 60% said that the girl was guilty, despite the fact they had not seen her commit a crime

Conclusion:

These results highlight the issue of post-even discussion and the powerful effect this can have on the accuracy of eyewitness testimony.

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Evaluation:

-The results of Gabbert et al. also have questionable ecological validity. The participants in the co-witness condition witnessed different perspectives of the same crime, as would typically be the case in real life crimes. However, like Loftus and Palmer, these witnesses knew they were taking part in an experiment and were more likely to have paid close attention to the details of the video clip. Therefore, these results do not reflect everyday examples of crime, where witnesses may be exposed to less information.

-Gabbert et al. tested two different populations, university students and older adults and found little difference between these two conditions. Therefore her results provide good population validity and allow us to conclude that post-even discussion affects younger and older adults in a similar way.

 

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Evaluation

-Although Gabbert’s results provide an insight into the effect of post-event discussion on the accuracy of eyewitness testimony, we are unable to conclude why the distortion occurs. The distortion could be the result of poor memory, where people assimilate new information into their own accounts of the event and are unable to distinguish between what they have seen and what they have heard. On the other hand, it could be that the distortion occurs due to conformity and the social pressure from the co-witness.

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