Factors affecting accuracy of eyewitness testimony 2 Flashcards
what else affects EWT?
Anxiety
who are the main researchers?
Johnson and Scott 1976
what was the aim of experiment?
to investigate the effect of anxiaty on perofrmance and eyewitness testimony
what was the procedure of experiment?
-lab + ppts + idiv design
-waiting in the lobby
-reseptionist goes
ppts overheard an argument
1. hearinig screams about broken equipment, an idiv walks out of the lab with grease on his hands = no weapon condition
2. argumneet, screams, chairs being thrown and breaken, an indiv walks holding a letter opener in blood/or knife =weapon condiiton
both groups shown 50 photos, one of the photos could be / could be not the photo of the indiv who left the lab
what were the results of experiment?
No weapon: 49% correct
Weapon: 33%
what was the conclusion of experiment?
exposed to knife = higher levels of anxiety,focused their attention on the weapon rather than the person
called weapon-focus affect
anxiety associated with knife reduced accuracy of the eyewotness testimony
who talked about positive affect of anxiety on performance
Christianson + Hubinette 1993
what did Christianson and Hubinette said in 1993
anxiety creates more enduring and accurate memories
ivolutionary: important to remeber emotionally important events, so you can identify them and recall how to repsond
Chrisitionson and Hubinette 1993 experiment
sweden
crime
interwied eyewitnessess
directly involved =higher EWT accuracy
70% accuracy on average
anxiety may benefit
what is Yerks - Dobson law
not a huge amount of anxiety actually improves the performace, ppts are pushed to dif levels of anxiety and so respond diff
low and high levels : -ive effect
+ graph
eval 1 top
some researches criticised that wepaon affect may actually not be due to highe anxiety, but rather something else
eval 1 point
Pickel (1998) did a study, when an indiv walekd into the hairdressing salon, holding scissors (high threat, low surprise), holding a handgun (high threat, high surprise), wallet (low threat, low surprise) and finally a raw chicke (low threat, high surprise)
found that identification was least accurate when surprise was high - gun and chicken
eval 1 tail
it can be criticesed, that a gun also increased anxiety as well as surprise, but at the same time - chiken which had no threat, prompted the same results. leading to considering that high surprise may actually cause low accuracy EWT
showing that perhaps johnson and Scot 1976 study wasnt that valid
eval 2 top
critics of the weapon affect, suggest that the violence of the crime affects the accuracy of recall, not actually the weapon
eval 2 point
Christionson and Hubinette1993 concerned a sreal life vilonet crime. they have noticed that many of the real life and study crimes didnt have violence in them.
additionally, Halford and Milne 2005 found that when a crime had violence in it, the accuracy of EWT
was actually better, than without violnece
eval 2 tail
this shows that the quetion of how anxiety affects the EWT is not that simple, it may be that the surprise, or violence affect it, but it is hard to say which way - positive or negative
eval 3 top
there has been an alternative explanantion of Yerkes Dodson model and therefore how anxiety affects performance
eval 3 point
the theory predicts that whn physiological arousal increases beytond normal level, the inverted U hypothesis predics gradual decrease in perfirmance (the normal graph)
however, Fazey and Hardy 1988 observed that sometimes there is a catastrophic decline in performance which can be due to the mental anxiety (worry),
suggesting the inverted-U hypothesis takes into account only physical arousal of anxiety[https://www.leadershipandsport.com/catastrophe-theory-in-sport/]
they called it catostrophic theory
eval 3 tail
suggesting that Yerkes and Dodson thery is quite simpistic
eval 3 double
additionally, the extraneous variable that many reserchers couldnt controll in that area os indiv dif
Bothwell et al 1987: ppts were tested for personality characteristcs, and divided into two groups: neurotic and stable
both groups were epxosed to the same crime, snf the difference was clear, that the stable group had increased level of accuracy correlating with increased level of anxiety while the neurotic group didint have that level of accuracy
suggesting that indiv dif play a significant level of accuracy in EWT
