Pozzulo et al

• A line-up is a source of evidence used by the legal system to identify a suspect, by showing the witness an array of photos of the suspects and asking them to point to the one they believe is the offender.
• Eyewitness testimony is evidence provided by an individual who has seen or heard a crime being committed, which is then used by the legal system.
• A false positive response is giving a positive but incorrect answer.
• We aren’t always accurate in recalling memory, as we only store information we attend to using our five senses. This links to the first assumption of the cognitive approach, which states that our brain works like a computer.
• The aim of Pozzulo’s study was to study social effects on child eyewitness testimonies. Social factors being tested include

  • child perceiving the person asking the question as an authority figure
  • child feeling they must choose someone and less likely to say “I don’t know “
  • child pressured to give an answer, comply and not be in trouble.
• He recruited 59 child participants aged 4-7 years. 21 were females and 38 were males. They were recruited from 3 private schools in Ontario.
• 53 adult participants, aged 17-30 years were recruited from a participant panel at Eastern Ontario University. 36 were females and 17 were males.
• He tested for 3 IVs, which were:

  • age - adult or child
  • line up - target present or absent — every line up had a blank silhouette to allow ps to select even when there’s no target.
  • familiarity and cognitive load - cartoon ( Dora & Diego ) or human faces
• Pozzulo used a between subjects design with 3 independent variables and one dependent variable. The dependent variable was accuracy of identification.
• The human faces were of 2 Caucasian students, 1 male and 1 female.
• A 6 second black and white video was shown to participants with the 2 targets. Their faces were shown for 2 to 3 seconds.

  • in the human condition, the woman was brushing her hair, while the man was putting on a coat.
  • in the cartoon condition, dora was talking to the audience while Diego was putting on gloves. The cartoon videos had color but no sound.
• In the photographs presented to the participants, the targets were wearing different clothes than in the video. Foils were chosen by 3 raters, who compared them to the targets. The foils were said to have similar facial features, hair length and color. The photos only showed the face, neck and tops of the shoulders.
• The positions of targets and foils were randomized for all target present trials.
• A control used in the study was that the type of trial was counterbalanced.
• A demographic sheet and consent form was completed by the parents of children to ensure they were familiar with the cartoons
• ETHICS:

  • only children with consent participated - informed consent
  • children were made comfortable by doing crafts before the experiment, and were monitored for stress, anxiety and fatigue throughout the experiment - protection from harm
  • researchers were introduced as a group of university students doing a project on computer games and TV - deception
  • researchers made it clear to participants that they could leave at any time - right to withdraw
• Procedures were standardized. 3 female experimenters all dressed in professional casual clothing.
• As a filler, participants were asked an open end question to describe everything in the video. This gave a 2 minute gap between exposure to the video and selecting the target. Increased realism.
• Target Present Results:

  • child participants were more accurate at identifying cartoons ( 0.99 ) compared to human faces ( 0.23 )
  • adult participants were also more accurate at identifying cartoons ( 0.95 ) compared to human faces ( 0.66 )
• Target Absent Results:

  • child participants had a higher correct rejection rate for cartoons ( 0.74 ) compared to humans ( 0.45 )
  • adult participants had a higher correct rejection rate for cartoons ( 0.94 ) compared to humans ( 0.70 )