factors affecting the accuracy of eyewitness testimony - anxiety Flashcards
what is anxiety?
a state of emotional and physiological arousal. it can be caused by stressful events such as witnessing crimes.
what is the effect of anxiety on EWT?
has strong emotional and physical effects. but it is not clear whether these effects make eyewitness recall better or worse.
research supports both possibilities.
describe the theory that anxiety has a negative effect on recall.
(weapon focus).
anxiety creates physiological arousal in the body which prevent us paying attention to important cues, so recall is worse. one approach to studying anxiety and EWT is to look at the effect of the presence of a weapon which creates anxiety. this leads to a focus on the weapon, reducing a witnesses recall for other details of the event.
describe the research into weapon focus that supports anxiety has a negative effect on recall.
(Johnson and Scott, 1976)
ptps believed they were taking part in a lab study.
while seated in a waiting room ptps in the low anxiety condition heard a casual conversation in the next room and then saw a man walk past them carrying a pen with grease on his hands.
other ptps overheard a heated argument, accompanied by the sound of breaking glass. a man walked out of the room, holding a knife covered in blood - high anxiety condition.
ptps later picked the man out from a set of 50 photos, 49% who had seen the man carrying the pen were able to identity him. 33% for the blood covered man.
the tunnel theory of memory argues that people have enhanced memory for central events. weapon focus as a result of anxiety can have this effect.
describe the theory that anxiety has a positive effect on recall.
witnessing a stressful event creates anxiety through physiological arousal within the body.
the fight or flight response is triggered, increasing alertness. this may improve memory for the event as we become more aware of cues in this situation.
describe the research into the theory that anxiety has a positive recall.
(Yuille and Cutshall, 1986)
conducted a study of an actual shooting in a gun shop in canada. the shop owner shot a thief dead. there were 21 witnesses - 13 took part in the study.
they were interviewed 5 months after the incident and these interviews were compared with the original police interviews at the time of the shooting. accuracy was determined by the number of details reported in each account.
the witnesses were also asked how stressed they felt at the time of the incident (on a 7 point scale) and whether they had any emotional problems since the event.
witnesses were very accurate in their account - little change in the amount recalled after 5 months. some details were less accurate - e.g. age/height/weight estimates.
ptps who reported highest levels of stress were the most accurate (88%) compared to less-stressed (75%).
suggests anxiety does not have a detrimental effect on EWT in a real world context and may even enhance it.1
what does the Yerkes-Dodson law state about the relationship between emotional arousal and performance?
looks like an inverted ‘U’.
performance will increase with stress, but only to a certain point, where it decreases drasitically.
describe the explanation of the contradictory findings of research into the effect of anxiety on EWT.
according to Yerkes and Dodson, the relationship between emotional arousal and performance looks like an inverted U.
A researcher reviewed 21 studies of EWT and noted contradictory findings on the effect of anxiety.
used the YD law to explain the findings.
when we witness a crime we become emotionally and physiologically aroused. lower levels of anxiety produce lower levels of recall accuracy, and then memory becomes more accurate as the level of anxiety increases.
however, there is an optimum level of anxiety, which is the point of maximum accuracy. if a person experiences any more arousal, then their recall suffers a drastic decline.
discuss internal validity of research into anxiety as a factor affecting EWT.
one limitation of the study by Johnson and Scott is that it may not have tested anxiety.
the reason ptps focused on the weapon could have been because they were surprised at what they saw rather than scared.
researchers conducted an experiment using scissors, a handgun, a wallet and a raw chicken as the hand held items in a hairdressing salon video (where scissors would be high anxiety, low unusualness).
EWT was significantly poorer in the high unusualness conditions (chicken and handgun).
this suggests that the weapon focus effect is due to unusualness rather than the anxiety and therefore tells us nothing specifically about the effects of anxiety on EWT.
discuss support for positive effects as a strength of anxiety as a factor affecting the accuracy of EWT.
another strength is evidence showing that anxiety can have positive effects on the accuracy of recall.
researchers interviewed 58 witnesses to actual bank robberies in Sweden. some of the witnesses were directly involved (e.g. bank workers) and some were indirectly involved (e.g. bystanders).
the researchers assumed that those directly involved would experience the most anxiety. it was found that recall was more than 75% accurate across al witnesses. the direct victims (most anxious) were even more accurate.
these findings from actual crimes confirm that anxiety does not reduce the accuracy of recall for eyewitnesses and may even enhance it.
HOWEVER -
the researchers interviewed their ptps several months after the event, therefore they had no control over what happened to their ptps in the intervening time (e.g. post event discussion).
the effects of anxiety may have been overwhelmed by these other factors and impossible to assess by the time the ptps were interviewed.
therefore it is possible that a lack of control over confounding variables may be responsible for these findings, invalidating their support for the theory.
discuss issues with the inverted U theory.
the theory appears to be a reasonable explanation of the contradictory findings linking anxiety with both increased and decreased eyewitness recall.
on the other hand, it ignores the fact that anxiety has many elements - cognitive, behavioural, emotional and physical.
it focuses on just physical and emotional arousal and assumes that this is the only aspect linked to EWT. but the way we think about the situation may also be important.
this suggests that the theory is reductionist, limiting its validity in explaining the contradictory findings linking anxiety with EW recall.
