Pozzulo et al. (False Memories and Eyewitness Testimony) (2011)

Cognitive approach

A psychological perspective that focuses on mental processes and how they influence behavior.

False memory

A piece of stored information that an individual believes to be an accurate memory but is actually the result of later additional and untrue information.

Eyewitness testimony

Evidence provided by an individual who has seen or heard a crime being committed.

Line-up

A procedure used by the legal system where a witness is shown a group of people or array of photographs and asked to identify the perpetrator of a crime.

False positive response

Giving an affirmative but incorrect answer to a question, such as mistakenly identifying an innocent person in a line-up.

Target-present line-up

A line-up where the perpetrator of the crime is among the individuals presented to the witness.

Target-absent line-up

A line-up where the perpetrator of the crime is not among the individuals presented to the witness.

Identification

The act of correctly selecting the perpetrator of a crime from a line-up.

Rejection

The act of correctly stating that the perpetrator of a crime is not present in a line-up.

Cartoon characters

Animated characters used as targets and foils in the line-up procedure.

Human faces

Real photographs of individuals used as targets and foils in the line-up procedure.

Social factors

Influences from the social environment that can affect decision-making and behavior.

Cognitive factors

Influences from mental processes and information processing that can affect decision-making and behavior.

Ecological validity

The extent to which research findings can be generalized to real-world settings and situations.

Demand characteristics

Cues or subtle hints that participants pick up from the experimenter or experimental setting that may influence their behavior or responses.

Ethical issues

Considerations related to the potential harm or benefit to participants and society in conducting research.

Validity

The extent to which a study accurately measures or reflects the concept or phenomenon it claims to be studying.

Nature versus nurture

Debate about the relative importance of genetic factors (nature) and environmental influences (nurture) in shaping behavior and development.

Theory of mind

The ability to understand and attribute mental states to oneself and others, including beliefs, desires, and intentions.

Psychology being Investigated

Are children reliable witnesses for crimes.

Background

Pozzulo's study explores how memory and cognition develop in children, affecting their ability to recall and identify individuals as eyewitnesses. The research investigates age-related differences in accuracy, susceptibility to leading questions, and responses to target-present and target-absent lineups. It also compares child and adult eyewitness abilities to understand factors that influence them.

Aims

1. Determine the Role of Social vs. Cognitive Factors in Lineups - The study sought to assess whether false identifications in target-absent lineups are more influenced by social pressures rather than cognitive abilities. This was tested using a lineup task with low cognitive demands, where a high correct identification rate was expected.

2. Compare False Positive Rates Between Children and Adults - The study hypothesized that while children and adults might have similar correct identification rates in easy lineups, children would show a higher rate of false positives in target-absent lineups, indicating a greater susceptibility to social influences compared to adults​​.

Sample

Children - 59 young children aged 4 to 7 years (mean age 4.98 years), including 21 females and 38 males, were recruited from pre-kindergarten/kindergarten classes from three private schools in Eastern Ontario, Canada.

Adults - 53 adults aged 17 to 30 years (mean age 20.54 years), including 36 females and 17 males, were recruited from the Introductory Psychology Participant Pool at an Eastern Ontario university.

Experimental Design

Independent measures design and repeated measures

The study used a 2 (age group - young children vs. adults) × 2 (target type - cartoon vs. human) × 2 (lineup type - target-present vs. target-absent) mixed factorial design.

Type

Laboratory Experiment

Independent Variable (IV)

1. Age of the participants (children vs. adults),

2. type of target (cartoon vs. human),

3. lineup type (target-present vs. target-absent).

Dependent Variable (DV)

Correct identifications in target-present lineups and correct rejections in target-absent lineups, to assess the influence of social and cognitive factors on the participants' decision-making process​​.

Quantitative Results

Correct Identification Rates for Human Faces - For human faces, the average correct identification rate was 0.23 for children and 0.66 for adults.

Correct Identification Rates for Cartoon Faces - For cartoon faces, children had an average correct identification rate of 0.99, while adults had a rate of 0.95.

Comparison Between Human and Cartoon Faces - Children were significantly more accurate in identifying cartoon faces (0.99) compared to human faces (0.23), with a statistically significant difference (X^2(1, N=116)=66.10, p=.001). Adults also showed higher accuracy with cartoon faces (0.95) compared to human faces (0.66), with a significant difference (X^2(1, N=103)=11.25, p=.001).

Children vs. Adults in Identifying Cartoon Characters -

Children and adults showed a comparable correct identification rate for cartoon characters (0.99 vs. 0.95, respectively; X^2(1, N=110)=.39, p=.53).

Children vs. Adults in Identifying Human Faces - Children had a significantly lower rate of correct identification for human faces compared to adults (0.23 vs. 0.66; X^2(1, N=168)=18.83, p=.001)​​.

Qualitative Results

Free Recall Descriptions - Participants were asked to describe everything they could remember about each video clip. The researchers recorded responses from child participants, while adult participants recorded their own responses. This was used as a filler task between the video exposure and lineup presentation, with approximately 2 minutes between each video exposure and lineup presentation.

Procedure Differences Between Children and Adults - The study's procedure varied slightly for children and adults, with different approaches to introducing the task and obtaining consent. The study ensured comfort and reduced stress for children, using crafts and gentle questioning. Adults were introduced to the study in a more formal laboratory setting, asked to recall details in writing, and given demographic questionnaires after the task completion.

Conclusions

Role of Social vs. Cognitive Factors - The study assessed whether children's false positive responses in target-absent lineups are more influenced by social factors than cognitive factors. It found that although children could correctly identify familiar targets (cartoon characters) with nearly 100% accuracy, they had a significantly lower rate of correct rejections in target-absent lineups compared to adults. This suggests that social factors, rather than cognitive ability, play a more significant role in children's false positive responses.

Differences Between Children and Adults - The study highlighted notable differences in how children and adults respond to lineup tasks. Children showed a lower correct rejection rate for both familiar (cartoon characters) and unfamiliar (human faces) targets compared to adults. This indicates that children are more prone to falsely identify someone in target-absent lineups, regardless of the target's familiarity.

Implications for Eyewitness Identification - The findings of this study have important implications for understanding children's identification evidence in legal settings. Given the lower correct rejection rates among children, the study suggests that children's eyewitness testimony, especially in target-absent lineups, might be less reliable due to higher susceptibility to social influences. This points to the need for careful consideration and potentially modified procedures when involving child eyewitnesses in legal contexts​​.

Strengths

Control of Variables - By calculating mean correct identification rates for human and cartoon faces separately for each child, the study controlled for target-specific peculiarities, which could otherwise skew the results. This methodological precision ensured that the findings were more likely to reflect general patterns rather than anomalies associated with particular targets.

Counterbalancing and Randomization - The positioning of targets/replacements in the lineups was randomized, and the order of video and photoarray presentation was varied. This counterbalancing reduced potential biases and order effects, thus enhancing the internal validity of the study.

Safeguarding Participants' Comfort and Well-being - The study took several steps to ensure the comfort and well-being of the child participants. For instance, children were introduced to the study in a non-threatening manner, and the researchers engaged them in crafts before starting the experiment to establish a comfortable environment. This approach reduced anxiety and stress, which is crucial when working with young children in a research setting.

Weaknesses

Limited Age Range and Demographics of Participants - The study focused on a specific age group of children (4- to 7-years-old), which limits the generalizability of the findings to other age groups. The developmental differences in memory and suggestibility can vary significantly across different age ranges in childhood.

Use of Familiar vs. Unfamiliar Targets - The study compared familiar cartoon characters with unfamiliar human faces. While this design provided insights into the influence of familiarity on identification accuracy, it might have introduced a bias. Children are generally more engaged with and better at recognizing familiar cartoon characters, which could lead to an overestimation of their identification abilities in more realistic scenarios, where targets are likely to be unfamiliar.

Ecological Validity - The procedure involved showing video clips followed by a lineup identification task, which may not fully replicate the complexities and stressors of real-world eyewitness situations. The ecological validity of the study could be questioned, as the controlled environment of a research setting differs significantly from the often chaotic and stressful circumstances in which eyewitness identifications typically occur.

Application to everyday life

Pozzulo et al. demonstrate that children would not be as reliable witnesses as adults in everyday life. In a police line-up it is unknown whether the actual perpetrator of the crime is present and children are more likely to make errors when the real target is absent, that is, to produce false positive responses. However, this difference is more likely to be because of social reasons than cognitive ones. In other words, it is due to the social situation rather than because children have worse memories. This finding is important as it could be used to improve the reliability of child witness information. This means that the next step is to investigate ways to combat the social factors that reduce the accuracy of witness identifications by children.

Individual versus Situational Explanations

The effect Pozzulo et al. found was a social one: the relatively poor performance of child witnesses in target-absent line-ups was due to social demands, such as feeling pressured. Although it may appear that the difference in accuracy between children and adults should have an individual explanation, such as poorer cognitive abilities of children, the evidence from Pozzulo et al. shows that this is unlikely.

Children as Participants

The study by Pozzulo et al. demonstrates effective ways to successfully conduct research using children.

Practical changes were made to the procedure to ensure the children could access the tasks and respond easily, such as a researcher recording the open filler task and the use of pointing to record the children's line-up responses. The ethical procedures also differed for the child participants, such as the right to withdraw being given and consent being gained by explaining to them in a child-friendly way, settling them down and monitoring their fatigue, anxiety and stress.

Ethical Issues

Ethical issues are not only about the implications for the participants of research but also for wider society.

Clearly, the findings of this study make a valuable contribution to the use of children as witnesses and therefore help to improve lives. However, any potential benefits must be measured against potential damage to the participants. If the children in this research had been victims of real crimes, this would have risked considerable potential for harm. However, the experimental situation was not crime-related and the children were not at risk. Furthermore, consent was gained from the parents/guardians of each child, as well as informed consent being gained from the children themselves in a child-friendly way. Finally, the children's comfort and their right to withdraw were ensured as well as ongoing monitoring of their fatigue, anxiety and stress to protect them from harm.