Factors Affecting EWT: Anxiety Flashcards
Define anxiety
A state of emotional and physiological arousal. The emotions include having worried thoughts. Physical changes include an increased heart rate and stimulation of sweat glands. Anxiety is a natural reaction to stressful situations, but can affect the accuracy and detail of EWT
Who demonstrated that anxiety has a negative effect on EWT?
Johnson and Scott (1970s)
What was the aim of Johnson and Scott’s lab study?
To investigate the effect of weapons (which provoke anxiety) on accuracy of recall of witnesses due to weapon focus
- weapon focus effect= witnesses’ attention is drawn to the weapon held by a criminal and therefore other details about a scenario are missed and so not committed to memory
What was the procedure of Johnson and Scott’s lab study?
- volunteer sample
- led participants to believe they were going to take part in a laboratory study and were made to wait in a waiting room
- a receptionist who was seated excused herself to run a job, leaving the participant alone
- while sitting alone in the waiting room, the participant heard an argument in the next room
- experiment used independent groups designs as participants were then exposed to one of 2 conditions:
a) ‘low-anxiety’ condition: a male confederate walked through the waiting area carrying a pen with grease on his hands
b) ‘high-anxiety’ condition: heated argument participant heard was accompanied by the sound of breaking glass- a male confederate then walked into the waiting area holding a paper knife covered in blood
What were the findings and conclusions of Johnson and Scott’s lab study?
- HIGH-ANXIETY CONDITION LED TO LOWER CORRECT IDENTIFICATIONS: the participant in the waiting room was then later asked to identify the male confederate from a set of 50 photographs:
- 49% of the participants who had seen the man carrying the pen ‘low-anxiety’ condition were able to correctly identify him
- whereas in corresponding ‘high-anxiety’ condition who had seen the man carrying the knife, was just 33%
- this may be explained by tunnel theory of memory:
- argues that a witnesses’ attention may be diverted and narrows to focus on a weapon, because it is a source of danger and anxiety, supporting the weapon focus explanation
Who conducted research to show than anxiety has as positive effect on EWT?
Yuille and Cutshall (1980s)
What was the aim of Yuille and Cutshall’s study?
Investigate the effect of anxiety on EWT (accuracy of recall)
What was the procedure of Yuille and Cutshall’s study?
- interviewed 13 witnesses to a shooting 5 months after the event
- this study made use of a real-life crime that occurred involving a real-life shooting in a gun shop in Vancouver, Canada where the shop owner shot a thief dead
- there were 21 witnessed and 13 witnesses agreed to take part in the study
- interviews took place approximately 5 months after the event and were compared to the original police interviews made at the time of the shooting
- witnesses were also asked to rate how stressed they had felt at the time of the accident, using a 7-point scale
- so collected both qualitative and quantitative data
What were the findings and conclusions of Yuille and Cutshall’s study?
- ACCURACY VERY HIGH AFTER 5 MONTHS: the witnesses were very accurate in their accounts and there was little change in the amount or accuracy after five months- though some details were less accurate such as the colour of items and age/weight/ height
- positive correlation found between levels of stress reported and accuracy of recall:
- those participants who had reported the highest levels of stress were most accurate (about 88% compared to 75% for less-stressed group)
What is able to explain the contradictory findings between Johnson and Scott and Yuille and Cutshall?
- Inverted ‘U’ relationship between arousal and performance
- Deffenbacher applied the Yerkes-Dodson Law to EWT:
- lower levels of anxiety produce lower levels of recall accuracy
- accuracy increases with anxiety up to an optimal point
- a drastic decline is seen when an eyewitness experiences more stress than the optimal point = anxiety becomes counter-intuitive
According to ______ and ______ the relationship between emotional arousal and performance looks like an ‘inverted U’ = states that performance increases with stress, but only to a certain point (optimum point), where it decreases drastically
Yerkes and Dodson = Yerkes-Dodson Law
What are the evaluation points for effect of anxiety of EWT?
❌ one limitation of Johnson and Scott’s study is that it may test surprise rather than anxiety (Pickel)
❌ ethical issues associated with research into effect of anxiety on EWT
❌ field studies lack control
❌ inverted- U explanation may be too simplistic
Explain how one limitation of Johnson and Scott’s study is that it may test surprise rather than anxiety (Pickrell)
- the reason participants may have focused on the weapon may be simply due to the fact that they’re surprised by what they see rather than anxiety and fear
- Pickel conducted an experiment using scissors, handgun, wallet and raw-chicken as a hand-held items in a hairdressing salon
- eyewitness accuracy was significantly poorer in chicken and handgun conditions
- this suggests that weapon focus effect is due to unusualness of a situation rather than anxiety/threat and therefore tells us very little specifically regarding the effects of anxiety on EWT
Explain how there are ethical issues associated with research into effect of anxiety on EWT
- creating anxiety in participants is extremely risky
- it is potentially unethical as it may subject people to psychological harm, possibility going against one of BPS code of ethics main principle: responsibility (avoiding harm to clients or participants)
- if the participants were subject to stress or embarrassment, they may require counselling which the researchers should have provided to avoid any ethical concern backlash
- ultimately, this is why real-life studies are so beneficial- such as Yuille and Cutshall who interviewed 13 witnesses to a real-life shooting in Vancouver, so it may be argued that there is no need to create it
Explain how field studies lack control
- despite Yuille and Cutshall interviewing 13 witnesses to a real-life shooting = findings cannot be disputed to lack ecological validity
- there are still issues associated with field studies into the effect of anxiety on EWT
- most importantly, they lack control compared to lab studies
- researchers usually interview real-life eyewitnesses some time after the event; all sorts of things will have occurred spans happened to the witnesses in the meantime that the researchers have no control over
- for example, in Yuille and Cutshall’s study, co-witnesses may have discussed the shooting, exchanging (mis) information contaminating witnesses’ memories
- this is a limitation of Yuille and Cutshall’s study as it may be possible that extraneous variables such as post-event discussion may be responsible for the accuracy of recall rather than anxiety as it is difficult to isolate these variables due to the nature of the study
