Memory

Question 1

Multi-Store Model?

Answer 1

Arkinson and Shiffrin (1968) proposed earliest model of memory - MSM,

They suggested memory is made up of three components: sensory register, short-term me money and long-term memory,

Memories are formed sequentially and information passes from one component to the next (linear fashion),

Each of the three components has a specific coding, capacity and duration.

Question 2

Eyewitness Testimony?

Answer 2

Is the evidence given in court or a police investigation by someone who has witnessed a crime or accident.

Question 3

Factors That Can Effect Accuracy Of Eyewitness Reports?

Answer 3

Misleading information through leading questions,
Post-event discussion,
Anxiety.

Question 4

Misleading Information - Loftus + Palmer, Experiment 1?

Answer 4

1974,

Misleading information is given through leading quesrtions,

Aim: To investigate the effect of leading questions on the accuracy of eyewitness testimony,

Method: Sample was 45 American students, divided into 5 groups of 9. Independent measures design; all watched a video of a car crash and then asked specific questions about the speed of the cars. Loftus and Palmer manipulated the verb used in the question; “How fast were the cars going when they smashed/collided/bumped/hit/contacted with each other?”,

Estimated speed was affected by the verb used. E.g. participants given the word ‘smashed’ reported an average speed of 40.5 mph and participants who were given word ‘contacted’ reported an average speed of 31.8 mph. The difference was 8.7 mph.

Conclusion: Results show clearly that the accuracy of eyewitness testimony is affected by leading questions and that a single word in a question can significantly affect the accuracy of our judgements.

Question 5

Misleading Information - Loftus + Palmer, Experiment 2?

Answer 5

1974,

Aim: To investigate how leading questions can affect eyewitness testimony,

Method: Loftus + Palmer used a different sample of 150 American students, who were divided into three evenly-sized groups. All the students watched a 1 minute video depicting a car accident and were then given a questionnaire to complete. One group was asked “How fast were the cars going when they smashed into each other?”. Another group: “How fast were the cars going when they hit each other. The final group was not asked about the speed of the cars. All groups returned a week later and was asked, “Did you see any broken glass?” when there was no broken glass in video,

Results: 32% of group ‘smashed’ reported seeing broken glass. 14% of group ‘hit’ reported seeing broken glass,
12% of control group reported seeing broken glass,

Conclusion: The participants who were questioned using verbs ‘smashed’ and ‘hit’ were significantly more likely to report seeing broken glass. The verb ‘smashed’ has a connotation of faster speeds with broken glass which lead participants to report seeing broken glass. Their memory of the original video had been distorted by using these verbs. This shows the power of leading questions.

Question 6

Evaluation Of Loftus + Palmer?

Answer 6

Low Ecological Validity - Questioning participants about every day events like a car crash seems to be a genuine measure of eyewitness testimony. However, the participants watched a video of a car crash and witnessed the events unfold from start t finish. In everyday reports of a car crash, witnesses rarely see the whole event; they are either involved in the event directly, or see a small part of the event happen in their peripheral vision. Therefore, their results do not reflect everyday car accidents and we are unable to conclude if eyewitnesses to real car accidents, who would have a stronger emotional connection to the event, would be susceptible to leading questions in the same way,

Lacks Population Validity - Second weakness, their two experiments consisted of 45 american students and 150 american students from university of Washington. It is reasonable to argue that the students in their experiments were less experienced drivers, who may be less accurate at estimating speeds. Consequently, we are unable to generalise the results to other populations, for example, older and more experienced drivers, who may have more accurate judgement and therefore, not be as susceptible to lading questions,

Highly Controlled - Research took place in a university laboratory. This high degree of control reduces the chance of extraneous variables, increasing the validity of the research. Its easy for psychologists to replicated the research, to see if the results are achieved with a different population.

Question 7

Post-Event Discussion?

Answer 7

Post event discussion can lead to misleading information,

This is when the details of the crime or accident are discussed by the witnesses after the event has taken place.

Question 8

Gabbert Et Al?

Answer 8

2003,

Aim: to investigate the effect of post-event discussion on the accuracy of eyewitness testimony,

Method: The sample was 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 co-witness group were told that they had watched the same video; however, they had in fact seen different perspectives of the girl stealing. Participants in the co-witness group discussed the crime together. All of the participants completed a questionnaire, testing their memory of the event,

Results: 71% of the witnesses in the co-witness group recalled information they had not actually seen and 60% said that the girl was guilty even though they had not actually seen her commit a crime.

Conclusion: These results highlight the issue of post-event discussion and the powerful effect this can have on the accuracy of eyewitness testimony

Question 9

Evaluation Of Gabbert Et Al?

Answer 9

Low Ecological Validity: Participants in co-witness group viewed different videos of the crime as would typically be the case in real-life crime. However, as Loftus + Palmer’s research, these witnesses knew they were taking part in the experiment and were more likely to pay more attention to the video. Therefore, the results do not reflect everyday examples of crime,

Good Population Validity: Tested two different types of populations, university students and older adults and found little difference between the two groups results. Therefore, her results have good population validity and allow us to conclude that post-event discussion affects younger and older adults in a similar way,

No Conclusion - The research provides an insight into post-event discussion and the accuracy of witness testimony, however, it does not provide a reason as to why this occurs. The distortion could occur due to poor memory and assimilate new information into their own accounts of the event and are unable to distinguish between what they’ve seen and what they’ve heard. On the other hand, it could be that the distortion occurs due to conformity and the social pressure from the co-witnesses. Further research is required.

Question 10

Anxiety?

Answer 10

Can lead to misleading information from an eyewitness testimony,

Loftus (1979 - and not to be confused with the other Loftus + Palmer) reported the findings of Johnson + Scott (1976) who conducted an experiment to see if anxiety affects the accuracy of eyewitness testimony and facial recognition,

Aim: To investigate whether anxiety affects accuracy of eyewitness testimony,

Method: Participants were invited to a lab where they were told to wait in the reception area. A receptionist who was seated nearby excused herself to run an errand, leaving the participants alone. The experiment used an independent groups design, as participants were then exposed to one of two conditions: 1) In the ‘no-weapon’ condition, participants overheard a conversation in the lab about equipment failure. Thereafter, an individual (the target) left the lab and walked past the participants holding a pen, with his hands covered in grease. 2) In the ‘weapon’ condition, participants overheard a heated conversation and the sound of breaking glass and crashing hairs. This was followed by an individual (the target) running out the lab into the reception area, holding a bloodied letter-opening knife. Both groups were then showed 50 photographs and asked to identify the person who had left the lab. The participants were instructed that the target may/may not be in the photos,

Results: Those who had witnessed the man holding a pen correctly identified the target 49% of the time, compared to those who had witnessed the man holding a knife, who correctly identified the target 33% of the time,

Conclusion: Loftus claimed that the participants who were exposed to the knife had higher levels of anxiety and were more likely to focus their attention on the weapon and not the face of person, a phenomenon known as the weapon focus effect. Therefore, the anxiety association with seeing a knife reduces the accuracy of eyewitness testimony.

Question 11

Evaluation Of Anxiety As A Factor Of Eye Witness Testimony?

Answer 11

Criticism - Real life case study, Yuille and Cutshall (1986), contradicts the results of Loftus and the weapon focus affect.They investigated the effect f anxiety in a real life shooting, in which one person was killed and another person seriously injured. 21 witnesses were interviewed by police, 13 of which (aged 15-32) agreed to take part in Yuille and Cutshall’s follow up study 4-5 months later. They found that 13 witnesses who took part in the follow-up accurately recalled what happened, with only minor changed to their statement (height, weight). This shows that in real-life cases of extreme anxiety, the accuracy of eyewitness testimony is not affected,

Criticism - Ecological validity, although the participants were waiting in the reception area outside the laboratory, they may have anticipated that something was going to happen, which could have affected, which could have affected the accuracy of their judgement. The results from the real-life case studies (Yuille) refute the findings of Loftus and suggest that her results do not represent real-life cases of extreme anxiety,

Criticism - Ethical guidelines were broken. The participants were decieved about the nature of the experiment and not protected from harm. Loftus exposed some of the participants to a man holding a bloodied knife, which could have causes extreme feelings of anxiety. This is an issue, as these participants may have left the experiment feeling emotionally stressed and anxious, especially if they were sensitive to knife crime.

Question 12

Issues + Debates: Anxiety As A Factor Affecting EWT?

Answer 12

• Loftus and Palmer’s research is, like much reserach into memory, an example of experimental reductionism; the complex process of memory after a film of what would be traumatic in real life is reduced to the effect of the wording of a leading question (IV) on the eyewitness memory (DV). The research also suffers from cultural bias, as samples of participants were from either Britain or America,
• Loftus + Palmer, Yuille + Cutshall and Johnson + Scott all use a nomothetic approach to try to establish universal laws regarding eyewitness testimony, but their claims are based on small, non-representative samples.

Question 13

Why Was The Cognitive Interview Developed?

Answer 13

Was developed in 1985,in response to criticisms of the traditional police interview.

Fisher et al (1987) studied police interviews in Florida and found that witnesses were often given short,closed questions which attempted to elicit facts. Police would often ask questions in a sentence that was not synchronised with the events that had taken place.

Question 14

What Is The Cognitive Interview?

Answer 14

Geiselman et al (1985) developed the cognitive interview, identifying 4 key principles that they believed would enhance recall.

Question 15

Four Key Principles In Cognitive Interview?

Answer 15

Used to enhance recall.

Includes:

• Context reinstatement (CR),
• Report everything (RE),
• Recall from changed perspective (CP),
• Recall in reverse order (RO).

Question 16

CR?

Answer 16

Context reinstatement - one of the four key principles in the cognitive interview.

CR is when a person mentally recalls the context of the event. E.g. person might recall the time of day, weather, who they were with or even their feelings.

These details act as a trigger, to help the person remember more information.

There are clear links between this and context-dependant and state-dependant remembering.

Question 17

RE?

Answer 17

Report everything - one of the four key principles in the cognitive interview.

RE is when a person recalls every detail they can remember, even those that may seem trivial.

Question 18

CP?

Answer 18

Recall from changed perspective - one of the four key principles in the cognitive interview.

CP is when a person considers the event from someone else’s point of view.

E.g. they might consider what the offender saw.

Question 19

RO?

Answer 19

Recall in reverse order - one of the four key principles in the cognitive interview.

RO is when a person recalls the event in reverse chronological order.

Question 20

Key Study: Geiselman?

Answer 20

1985.

Aim: To examine the effectiveness of the cognitive interview.

Method: A sample of 89 students watched a video of a simulated crime. Two days later, they were interviewed using the standard police interview or the cognitive interview.

Results: The students who were interviewed using the cognitive interview recalled significantly more correct information than those interviewed using the standard police interview. The number of errors by both groups was similar.

Conclusion: The cognitive interview is effective in improving the quantity of information recalled and does not lead to an increase in incorrect information.

Question 21

Key Study: Geiselman - Quantitative Data?

Answer 21

Average number of correct items recalled in cognitive interview: 41.5
Average number of correct items recalled in police interview: 29.3

Average number of incorrect items recalled in cognitive interview: 7.3
Average number of incorrect items recalled in police interview: 6.3

Question 22

Evaluating The Cognitive Interview?

Answer 22

Strength - Support research, including Fisher et al (1989) who examined the effectiveness of the cognitive interview in real police interviews.

16 experienced detectives recorded a selection of their interviews, using the standard police interview. The detectives were then divided into 2 groups. One group was trained on the cognitive interview whilst the other group (control group) was left to use the police interview.
Their following interviews were recorded and analysed. The trained group elicited 46% more info after their training in comparison to the control group. 90% of this info was found to be true where possible. These results support Gieselman.

Weakness - Research has found that the cognitive interview increases quantity of information recalled but is still susceptible to misleading info. Centofanti & Reece (2006) showed participants a video of a bank robbery and then provided them with a misleading or neutral post- event summary. On average, the participants who were questioned using a cognitive interview, recalled 35% more information. Interviewers need to be careful that participants are not exposed to misleading info in the form of leading questions or post-event discussion.

Weakness/Strength - Kebbel & Wagstaff (1996) have found that police typically use interviewing techniques that limit the quantity of info provided, rather than using techniques that improve accuracy. Furthermore, the cognitive interview requires special training and many police forces have not provided more than the rudimentary training, which explains why the cognitive interview is not readily used.

Question 23

The Cognitive Interview: Issues + Debates?

Answer 23

In common with much of the research into memory, research into police interview procedures, and the subsequent development and testing of the cognitive interview technique, suffers from experimental reductionism: there could be many explanations for difficulties that victims and eyewitnesses experience in recalling an event, apart from the technique that is actually used to interview them.

For example, the research does not address a possible culture bias, in that the researchers and the participants are from a Western culture but the results are taken to apply to all cultures.

Question 24

Capacity?

Answer 24

Sensory Register - unknown but very large.

Short-Term Momory - limited 7+/-2 chunks of information. Jacobs (1887) and Miller (1956).

Long-Term Memory - unlimited.

Question 25

Duration?

Answer 25

Sensory Register - very limited (approximately 250 ms).

Short-Term Momory - limited (20 seconds). Peterson and Peterson (1959).

Long-Term Memory - Lifetime/years. Bahrick (1975).

Question 26

Coding?

Answer 26

Sensory Register - raw/unprocessed information. Information comes from all 5 senses.

Short-Term Momory - acoustic (sound). Baddeley (1966).

Long-Term Memory - semantic. Baddeley (1966).

Question 27

Research Investigating Multi-Store Model?

Answer 27

The multi-store model of memory has been investigated extensively, and research has provided support for the different components of the model.

• Miller (1956) supports the idea that our short-term memory has a capacity of 7+/-2 chunks of information.
• Baddeley (1966) supports the notion of different types of encoding in short-term memory and long-term memory.
• Peterson & Peterson (1959) support the idea of a limited duration in short-term memory.
• Barrett (1975) supports the idea of an unlimited duration in long-term memory.

Question 28

Key Study: Miller?

Answer 28

1956 - The Magical Number 7, Plus Or Minus Two.

Capacity Of Short-Term Memory:

Aim: To investigate the capacity of short term memory.

Method: Literature review of published investigations into perception and short-term memory, from 1930s to 1950s.

Results: This existing research suggested that organising stimulus input into a series of ‘chunks’ enabled short-term memory to cope with about seven ‘chunks’ and this way, more than seven digits, words or even musical notes could be remembered successfully. E.g. remembering 11 digits of a phone number in 4 ‘chunks’: 077…14…806…220. So we remember the chunks and not the numbers.

Conclusion: Organisation (or ‘encoding’) can extend the capacity of short-term memory and enable more information to be stored there, briefly.

Question 29

Evaluating Miller?

Answer 29

Strength - Miller’s theory is supported by psychological research. Jacobs (1887) conducted an experiment using a digit span test, to examine the capacity of short term memory for numbers and letters. Sample of 443 female students aged 8 to 19 from the North London Collegiate school. Participants had to repeat back a string of numbers or letters in the same order and the number of digits/letters was gradually increased, until the participants could no longer recall the sequence. Jacobs found that the students had an average span of 7.3 letters and 9.3 words, supporting Millers notion of 7+/-2.

Weakness - Although Millers theory is supported by psychological research, he did not specify how large each ‘chunk’ of information could be. Therefore, we are unable to conclude the exact capacity of short term memory. Consequently, further research is required to determine the size of information chunks to understand the exact capacity of short term memory.

Weakness - Finally, Millers research into short-term memory did not take into account other factors that affect capacity. For example, age could also affect short-term memory and Jacobs (1887) research acknowledged that short-term memory gradually improved with age.

Question 30

Key Study: Peterson & Peterson - Aim & Method:

Answer 30

1959.

Duration Of Short-Term Memory:

Aim: To investigate how different short intervals containing an interference task affected the recall of items presented verbally, and to infer the duration of short term memory.

Method: The participants were 24 male and female university students. The verbal items tested for recall were 48 three-consonant, nonsense syllables such as ‘JBW’ or ‘PXD’ spelt out letter by letter. These have since been named ‘trigrams’. There were also cards containing three-digit numbers such as ‘360’ or ‘294’. The researcher spelt the syllable out and then immediately said a three-digit number. The participant had to countdown backwards in either 3s or 4s (as instructed) from that number. This was to prevent repetition of the trigram by the participant. At the end of a present interval of between 3-18 seconds, a red light went on and the participant had to recall the trigram.

Question 31

Key Study: Peterson & Peterson - Results + Conclusion?

Answer 31

Results - Peterson and Peterson found that the longer the interval, the less accurate the recall. At three seconds, around 80% of the trigrams were correctly recalled, whereas at 18 seconds, only 10% were correctly recalled.

Conclusion - Short-term memory has a limited duration of approximately 18 seconds. Furthermore, if we are unable to rehearse information, it will not be passed to long-term memory, providing further support for the multi-store model and the idea of discrete components.

Question 32

Evaluating Peterson & Peterson?

Answer 32

1959,

Weakness - Peterson and Peterson used a sample of 24 psychology students, which is an issue for two weeks reasons. Firstly, the psychology students may have encountered the multi-store model of memory previously and therefore may have demonstrated demand characteristics by changing their behaviour to assist the experimenter. Secondly, the memory of psychology students may be different from that of other people, especially if they had previously studied strategies for memory improvement. As a result, we are unable to generalise the results of the study to non-psychology students.

Weakness - It could be argued that Peterson and Peterson’s study had low levels of ecological validity. In this study, participants were asked to recall three letter trigrams, which is unlike anything people would want to memorise in their everyday lives. As a result, we are unable to apply these results to everyday examples of memory and are unable to conclude if the duration of short term memory may be longer for more important information, such as vital phone numbers.

Strength - The study was highly controlled and took place in a lavatory of Indiana University. As a result, Peterson and Peterson had a high degree of control for extraneous variables, which makes their procedure easy to replicate to test reliability.