Factors Affecting the Accuracy of EWT
Description, AO1 – Anxiety and EWT:
There is conflicting evidence about the effect of stress and anxiety on the accuracy of EWT (i.e., the accuracy of witness recall).
- Laboratory based studies have generally shown impaired recall in people who have witnessed unpleasant or anxiety-inducing situations (e.g., research by Loftus).
- However, other research (e.g., Foster et al; Christianson and Hubinette) into real-life incidents involving high levels of stress, have shown that in such situations, memory can be detailed, accurate and long-lasting.
There isn’t a simple relationship between emotional arousal and the accuracy of EWT. Deffenbacher (1983) was one of the first to investigate the link between anxiety and EWT and after reviewing 21 studies, he found that accuracy is poor when emotional arousal is either high or low, but is better under conditions of moderate arousal.
Description, AO1 – Research into factors (anxiety) affecting the accuracy of EWT: Loftus (1979)
This study aimed to investigate effect of anxiety levels on the accuracy of eyewitness testimony
- Laboratory study Loftus (1979) asked participants to wait outside a room before the study began.
- Condition 1 heard what they believed to be an amicable discussion about equipment failure, after which a man came out with greasy hands, holding a pen.
- In condition 2, the participants heard a hostile discussion, followed by the sound of breaking glass and overturned furniture. The man then emerged from the laboratory holding a knife covered in blood.
- The participants were later asked to pick out the person they saw leave the room with the knife/pen from 50 photographs.
Those who had witness the man holding a pen correctly identified the target 49% of the time, compared to those who had witness the man holding a knife, who correctly identified the target 33% of the time.
Loftus believed that the anxiety caused by the weapon (i.e., blood –stained knife) narrowed the focus of attention for the witness and took attention away from the face of the man – therefore making their recall (EWT) less detailed and less accurate. The knife became the central detail and was what the participants focussed on and the man’s face became the peripheral detail, which meant that it was unlikely that it would be remembered accurately.
Evaluation, AO3 of Loftus (1979) research into the effects of anxiety on the accuracy of EWT
(1) Point: Further research from Deffenbacher et al (1983) supports the suggestion that anxiety affects the accuracy of EWT. Evidence: Deffenbacher et al concluded from meta-analysis that anxiety levels that are too low or too high negatively affect EWT accuracy suggesting that eyewitness testimony is impaired if a person becomes too anxious. Evaluation: This is positive because it is further evidence that high levels of anxiety can result in a false eyewitness testimony, as found in Loftus’ research, supporting the theory that anxiety affects EWT accuracy.
(1) Point: Research has contradicted Loftus’ study suggesting that anxiety can improve the accuracy of EWT. Evidence: For example, Christianson and Hubinette (1993) studied the recall of witnesses to real bank robberies. They found that increased arousal led to improvements in the accuracy of recall. Evaluation: This is a weakness as it goes against Loftus’ finding that anxiety reduces EWT accuracy and suggests that anxiety-creating situations don’t always divert attention from important features of the situation.
(2) Point: Loftus’s study can be criticised as being unethical. Evidence: For example, participants in condition 2 witnessed quite a disturbing scene – the confederate leaving the office holding the blood stained knife. Evaluation: This is a weakness because the studying can be seen to be breaching the BPS guidelines as Loftus hasn’t protected her participants from harm – such a scene may cause the participant a great deal of distress.