Factors affecting the accuracy of Eye-Witness Testimony - Anxiety Flashcards
What is the argument for anxiety having a negative effect on recall?
Weapon focus - anxiety creates physiological arousal which prevents us from paying attention to important calls, so recall is worse. One approach to studying this is to look at the effect of the presence of a weapon, which creates anxiety, and then reduces a witnesses recall for other details.
What was the Johnson and Scott study into anxiety having a negative effect on recall?
The participants believed they were taking part in a lab study. While in the waiting room the PPs in the low-anxiety condition heard a casual conversation in the next room then saw a man walk past with a pen. In the high-anxiety condition, they heard a heated argument, followed by breaking glass. A man walked out with a bloody knife.
What were Johnson and Scott’s findings?
THe participants later picked out the man from a set of 50 photos. 49% in the pen condition could identify him, and only 33% in the knife condition.
What is the argument for anxiety having a positive effect on recall?
Witnessing a stressful event triggers physiological arousal in the form of the fight-or-flight response. This increases alertness, and possibly improves memory as we become more aware of cues.
What was Yuille and Cutshall’s experiment into anxiety having a positive effect on memory?
They conducted a study of an actual shooting where the owner shot a thief dead. There were 13 witnesses interviews 4-5 months after the shooting to be compared with original police interviews. Accuracy was determined by amount of details in each account. The witnesses were also asked to rate how stressed they felt at the time of the incident and whether they had any emotional problems since.
What were Yuille and Cutshall’s findings?
The witnesses were very accurate both at the time and later. Those participants who were most stressed were 88% accurate compared to 75% for the less-stressed group. This suggests anxiety enhances recall.
How can we explain the contradictory findings of how anxiety effects memory?
The Yerkes-Dodson Law - an inverted-U graph where low arousal indicates low recall, medium arousal is high recall, but high arousal is low recall. This is due to the fight-or-flight response increasing recall to a point, after which the recall suffers a drastic decline.
What is the evaluation - Pickel?
Picked argued that they were testing unusualness instead of anxiety. Picked conducted an experiment using scissors, a gun, a wallet and a raw chicken. The two conditions that scored lowest on recall were the chicken and gun, suggesting that the weapon focus effect is due to unusualness rather than anxiety so does not tell us anything about how anxiety affects EWT.
What is the evaluation - Valentine and Mesout?
Supporting evidence - the researchers used an objective measure of heart rate to divide participants into high and low anxiety groups. In this study anxiety clearly disrupted the PPs ability to recall details. This suggests that a high level of anxiety has a negative effect on the immediate eyewitness recall of a stressful event.
What is the evaluation - Support for positive effects?
Researchers interviewed 58 witnesses to actual Swedish bank robberies. Some were directly involved and some just bystanders. Recall was over 75% accurate across all witnesses. The direct victims were more accurate. These findings confirm that anxiety does not reduce the accuracy of recall for eyewitnesses and may even enhance it.
What is the evaluation - contrived study.
The Swedish experimenters interviewed their PPs up to 15 months afterwards. They therefore had no control over what happened in the intervening time. The effects of anxiety may have been overwhelmed by other factors and impossible to assess by the time the PPs were interviewed. Therefore it is possible that a lack of control over confounding variables may be responsible for these findings, invalidating their support.
