Accuracy of EWT: Anxiety Flashcards
What is tunnel theory?
- It explains the weapon focus effect
- States that aspects of an event that are emotionally arousing causes our attention to be tunneled to a given thing, causing inaccuracy in our recall of other details of the event.
What is the weapon focus effect?
In crimes, the weapon may cause our attention to be drawn to it, causing us to ignore the wider details.
What are the positive effects of anxiety on EWT?
- High anxiety creates enduring and accurate memories.
- An evolutionary argument is it would be adaptive to remember events that are emotionally important so you could identify similar situations and recall how to respond.
Give research supporting that anxiety has a negative effect on accuracy
- Johnson and Scott investigated weapon focus effect.
- Participants were asked to sit in a waiting room where they heard an argument. A man ran through the room with either a pen covered in grease (low anxiety condition) or a bloody knife (high anxiety condition). Participants then had to identify the man from photos.
- They found the mean accuracy was 49% in identifying the man in the pen condition, compared to 33% in the knife condition.
Give research that studies if anxiety has a positive effect on accuracy
- Christianson and Hubinette questioned witnesses to bank robberies in Sweden. Witnesses were either victims (bank tellers and high anxiety) or bystanders (customers and low anxiety). Interviews happened 4-15 months after the event
- They found all witnesses were better than 75% accurate in recall, but those who were most anxious had the best recall. Showing anxiety doesn’t reduce accuracy of recall too much.
Describe the Yerkes-Dodson effect
Deffenbacher suggested the Yerkes-Dodson effect, when arousal is moderate then eyewitness accuracy (performance) would be enhanced. When arousal is too extreme then accuracy will be reduced (U-shaped curve)
Give evaluation for the effects of anxiety as an explanation for EWT accuracy (good external validity + counter)
- Christianson and Hubinette’s research has good external validity. As usually, studies into EWT rely on artificial crimes where participants have little consequences and no motivation in their testimony. But, their research was conducted on a real-life event where anxiety was genuine and their testimonies had consequences. Suggests it provides a useful and valid depiction of the role of anxiety on EWT.
- However there are issues with a lack of control over extraneous variables, e.g. post-event discussion may have occurred in between the time they were interviewed and the crime and researchers have no control over this.
Give evaluation for the effects of anxiety as an explanation for EWT accuracy (weapon focus effect was due to surprise)
- The weapon focus effect may be due to surprise rather than anxiety.
- Pickel arranged for participants to watch a thief enter a salon with scissors (high threat, low surprise), handgun (high threat, high surprise), wallet (low threat, low surprise) or a raw chicken (low threat, low surprise). Identification was least accurate in the high surprise rather than high threat.
- Supports weapon focus effect is related to surprise.
Give evaluation for the effects of anxiety as an explanation for EWT accuracy (contradictory findings)
- There’s contradictory findings so that it’s difficult to establish the effect of anxiety as many studies of anxiety didn’t involve violence.
- Halford and Milne found victims of violent crimes were more accurate in their recall of crime scene info than victims of non-violent crimes.
- Shows there is no simple rule about the effect of anxiety on accuracy of eyewitness testimony
Give evaluation for the effects of anxiety as an explanation for EWT accuracy (more complex than Yerkes-Dodson model)
- The relationship between anxiety and performance may be more complex than the Yerkes-Dodson model predicts as the model only accounts for physiological arousal.
- The catastrophe theory accounts for physiological and cognitive anxiety (worry). Suggesting that as physiological arousal and cognitive anxiety increase, there’s a sharp decrease in performance.
- Shows an alternative model fits better with research findings.
