factors affecting the accuracy of eyewitness testimony - anxiety Flashcards
anxiety
a high state of emotional and physical arousal.
the emotions include having worried thoughts and feelings of tension.
the physical changes include an increased heart rate and sweatiness.
anxiety is a normal reaction to stressful situations, but it can affect the accuracy and details of EWT.
anxiety has a negative effect on recall
anxiety creates physiological arousal in the body which prevents 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 witness’s recall for other details of the event.
procedure on the negative effects of anxiety
craig johnson and william scott (1976) did research on this. there participants believed they were taking part in a lab study.
while seated in a waiting room participants in the low-anxiety condition heard heard a casual conversation in the next room and then saw a man walked past them carrying a pen with grease on his hands.
other participants overheard a heated argument, accompanied by the sound of breaking glass. a man walked out the room, holding a knife covered in blood. this was the high anxiety condition.
findings and conclusions on the negative effects of anxiety
the participants later picked out the man from a set of 50 photos, 49% who had seen the man carrying the pen were able to identify him
the corresponding figure for the participants who had seen the man holding the blood-covered knife was 33%.
the tunnel of the story of memory argues that people have enhanced memory for central events. weapon focus as a result of anxiety can have this affect.
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.
procedure on the positive effects of anxiety
john yuille and judith cutshall (1986) conducted a study of an actual shooting in a gun shop in vancouver, canada. the shop owner shot a thief dead.
there where 21 witnesses - 13 took part in the study. they were interviewed 4 to 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 to rate how stressed they had felt at the time of the incident (on a 7-point scale) and whether they had any emotional problems since the event (e.g. sleeplessness).
findings and conclusions
the witnesses were very accurate in their accounts and there was little change in the amount recalled or accuracy after 5 months - though some details were less accurate, such as recollection of colour of items and age/height/weight estimates.
those participants who reported the highest levels of stress were most accurate (about 88% compared to 75% for the less stressed group).
this suggests that anxiety does not have a detrimental effect on the accuracy of EW memory in a real-world context and may even enhance it.
explaining the contradictory findings (1)
according to robert yerkes and john dodson (1908) the relationship between emotional arousal and performance looks like an inverted ‘U’.
kenneth deffenbacher (1983) reviewed 21 studies of EWT and noted contradictory findings on the effects of anxiety
he used the yerkes-dodson law to explain the findings.
explaining the contradictory findings (2)
when we witness a crime/accident we become emotionally and physiologically aroused.
that is, we experience anxiety (emotional) as well as physiological changes in our body (the fight or flight response).
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 optimal level of anxiety, which is the point of maximum accuracy. if a person (or EW) experiences any more arousal, then their recall suffers a drastic decline.
