10 Eyewitness Memory

Question 1

What is the misinformation effect?

Answer 1

Exposure to incorrect information about an event after it has occurred often causes people to incorporate this misinformation into their memories

Question 2

Discuss differences between physical and eyewitness evidence

Answer 2

Physical evidence (e.g. Hairs, fibre, DNA etc)

• Protocols for collecting, preserving and interpreting physical evidence are dictated largely by forensic scientists
• Protocols have a scientific foundation, grounded in what experts suggest are optimal ways to avoid contamination
• Physical evidence is often ‘circumstantial’

Eyewitness evidence
-Typically collected by non-specialists in human memory
-Protocols for collecting, preserving and interpreting eyewitness evidence has not incorporated scientific psychological research to the extent that it could
Often directly links a suspect to a crime

Question 3

How do we know eyewitness evidence is unreliable?

Answer 3

1. DNA exoneration case studies
2. Eyewitness research
   - Encoding: What happens at the scene of the crime
   - Storage: before we recall, retain the event memory and the person description for a period of time
   - Retrieval: often include system variables

Question 4

According to eye witness research, errors can occur at different stages so what errors occur at the Encoding stage?

Answer 4

We can’t change what happens at the scene of the crime but it is important that we understand how different features of the crime and the witness will affect how reliable and accurate the witness will be
-different factors can influence the accuracy of memory and these are called estimator variables (cannot be changed)

Question 5

According to eye witness research, errors can occur at different stages so what errors occur at the Storage stage?

Answer 5

The more duration in the storage phase, the more we’re likely to forget or encounter incorrect information through different sources

Question 6

According to eye witness research, errors can occur at different stages so what errors occur at the Retrieval stage?

Answer 6

• System variables are the variables we have control over and we have control over how we question witnesses about crimes and how we conduct identification parades
• Different procedures and different questions can influence how accurate the witness is likely to be

Question 7

What is an important thing to remember when questioning eyewitnesses after a specific event has just happened?

Answer 7

Try to question witnesses quickly after the event happens for most accurate results and a lot of bad stuff can happen if delayed for too long

Question 8

Why is it important to question witnesses after the event as soon as possible?

Answer 8

The longer the delay the more possible sources they will encounter the more likely they will encounter misinformation about the event and the more susceptible they are to the information as their memory trace faces

Question 9

What are three ways to encounter post-event information?

Answer 9

1. Leading questions about the event (smashed/hit car)
2. Hearing about the event from the media (white van, snipers in blue car)
3. Hearing about the event from other witnesses

Question 10

Describe research that demonstrates how leading questions about the event can lead to misinformation?

Answer 10

Participants showed film of traffic accident

Asked how fast they were going when the cars smashed/hit each other

One week alter, participants in the smashed condition were more than twice as likely to recall broken glass, when there was none

*The difference in one word changed people’s memory reports on what happens

Question 11

Describe research that demonstrates how hearing about an event through the media can lead to misinformation?

Answer 11

Participants shown pictures of shoplifting incident

Then read brief summary of the crime, which including some incorrect details

Participants incorporated the incorrect details from the summary into their memories

Question 12

What are the two types of co-witness information and what did the eyewitness survey reveal?

Answer 12

Direct transfer: witnesses discussing the event with one another
Indirect transfer: third party tells you about the information that another witness has said

Eyewitness Survey

• majority of witness’ report discussing event with a co-witness
• Main reason: providing information
• more witnesses reported they had been encouraged by the police to discuss event with co-witnesses

Question 13

What does the research on comparing ways to encounter misinformation reveal about type of information effects?

Answer 13

Study investigated the impact of different methods of encountering post-event information

	- Leading questions
	- Media report
	- Indirect co-witness information
	- Co-witness discussion with confederate
	- Control

No effect of post-event information method on memory accuracy for control items

For accurate information, direct and indirect co-witness conditions more accurate

For misleading information direct and indirect co-witness conditions less accurate

Question 14

Why is it important to study the co-witness discussion?

Answer 14

• Research has consistently shown that participants report misinformation that was previously stated by a co-witness during discussion
• Warnings not effective: only report what you remember from the video not what you heard from another person

This phenomenon has become known

	- Social contagion of memory
	- Memory conformity

No effect of co-witness discussion on identification decision

Question 15

What is the legal perspective on co-witnesses?

Answer 15

A witness’s assertions of relevant facts should be based upon his or her own experiences” and not those of another

Question 16

What did the police report as the benefits of discussion?

Answer 16

• Refresh and reinforce memory
• Recovery from trauma
• Witnesses with different stories impeded court
• Police officers discuss with one another

Question 17

What did the police report as impracticalities of preventing it

Answer 17

• Discussion prior to arrival
• Impossible to prevent
• Mother and child: can you really separate them? Unethical

Question 18

Why does the misinformation effect occur?

Answer 18

(1) Social and Demand Facors
- Response Bias

(2) Modification of the Memory
a. Alteration Theories
b. Co-existence Theories

Question 19

What do the alteration theories of misinformation believe?

Answer 19

Original information does not exist. Because:

• vacant spot explanation: misinformation is accepted because the individual failed to encode information
• overwriting explanation: post-event information overwrites original memory
• blend explanation: Ps encode misinformation as the original information, resulting in a blend

Implications:

• try to prevent people from getting misinfomation in the first place
• warnings about misinformation doesn’t seem to work
• no matter how hard they try, they can’t access original correct information

Question 20

Summary of what the alteration theory believes:

Answer 20

We can’t access the original memory, it’s gone and can’t access through questions so we have to try and prevent witnesses from encountering post-event information

Question 21

What do the co-existence theories of misinformation believe?

Answer 21

Both memory for the original event and misinformation are stored and each memory is capable of being recovered. Original memory is not replaced, but is less accessible than the subsequent misleading information.

Perhaps owing to; recency effect (more likely to remember things that happened recently), retroactive interference (what we learn after the fact can make it difficult to access what we originally learned)

Implications;

• original memory trace is there, just need to ask the right questions to be able to access correct information.
• can never really say if a memory is there or not

Question 22

What is a way to target the co-existence hypothesis?

Answer 22

Build different types of questions to access the specific memory

Question 23

What factors decrease susceptibility to misinformation effect?

Answer 23

• The misinformation blatantly contradicts what was originally witnesses
• Source of the misinformation in not credible
• They are forewarned that they may encounter misinformation. However, warning them that they have encountered information a week after the fact, doesn’t help combat the misinformation effect

Question 24

What factors increase susceptibility to misinformation effect?

Answer 24

• Age (young and old)
• Hypnosis
• Suggestibility
• Misinformation is repeated -> exposure
• Misinformation is peripheral -> not central to the crime

Question 25

What are the limitations of research on the misinformation effect?

Answer 25

Ethical constraints of laboratory research Ecological validity of lab findings

Question 26

What can be done to preserve memory integrity?

Answer 26

Statements should be obtained as soon as is practicable following an incident

Question 27

What are things that can be done to prevent misinformation effect?

Answer 27

An immediate-recall tool that elicits a comprehensive statement from eyewitnesses may increase the quality and quantity of accurate information that they provide -The self-administered interview is an example of such an immediate recall tool (paper and pencil self-explanatory response booklet)

Question 28

What are some problems with SAI?

Answer 28

- The paper format means that the tool is very generic and inflexible - The tool is only appropriate for one-off events, and not incidents that are repeated or ongoing - The tool does not accommodate the needs of different types of witnesses (e.g., lower literacy)

Question 29

What does most psychological research focus on?

Answer 29

On the malleability of eyewitness memory

Question 30

What are the three main theories that aim to explain why memories are malleable?

Answer 30

Alternation hypothesis, co-existence hypothesis and response bias Each theory has different practical implications

Question 31

What can facilitate eyewitness memory?

Answer 31

Immediate recall

Question 32

What do the social and demand factors of misinformation believe?

Answer 32

Response Bias in favour of post-event information Due to the recognition test procedure - Ps who don't remember/notice critical detail in the original event AND are not given any misinformation reply at the change rate - Ps who DO get misinformation, have no reason to doubt misinformation presented to them - But, even when asked free recall some people still note misinformation