factors affecting accuracy of EWT: anxiety Flashcards
how does anxiety have a negative effect on recall? (weapon focus)
-presence of weapon creates anxiety - leading to focus on weapon, reducing witness recall for other events
what was the procedure in johnson and scott weapon focus study?
-Ps in a lab study
-low anxiety conditon heard argument next door and man walk past them w pen in hand with grease
-other Ps heard heated arguement w breaking glass sound , man walked out knife covered in blood
-high anxiety conditon
what was found in johnson and scotts weapon focus study?
-from pctures of men, 49% were able to identify the man carrying pen
- 33% able to identify the man w a knife
-tunnel theory- ppl have enhanced memory for central events
in high anxiety condition = people focused more on the weapon due to anxiety.
how does anxiety have a positive effect on recall?
-flight or fight is triggered
-this increases alertness
-improve memory as u become more aware of cues
what was the procedure of yuille and cutshall for positive recall?
A study on an actual shooting involved a shop owner killing a thief, with 21 witnesses. They were interviewed 4–5 months later, and accuracy was measured by the number of details recalled. Witnesses also rated their stress levels at the time and reported any emotional problems since the event, such as sleeplessness.
what was the findings of yuille and cutshall?
-very accurate in accounts
-less accurate in details e.g age/ height/weight
- those w high level stress were most accurate(88%)
- 75% accuracy for less stressed
so anxiety may enhance EWT
what are the contradictory findings?
The Yerkes-Dodson law suggests that emotional arousal and performance follow an inverted U-shaped curve. Deffenbacher reviewed 21 studies and found mixed results. When witnessing a crime, emotional and physiological arousal increase, improving memory up to an optimal anxiety level. Beyond this point, excessive arousal impairs recall. Moderate anxiety enhances accuracy, but too much reduces it significantly.
Parker et al and natural disasters?
Natural disasters- most lab based and real life studies of anxiety is that only that compare high and low anxiety groups
-Yerkes and dodson law can’t be tested properly unless there’s moderate group too
- parker et al=decided to overcome this and interview people apart of a hurricane andrew (1992) in USA.
researchers defined anxiety in terms of amount of damage the Ps suffered to their homes
what did parker et al find?
-found a link between the level of recall and amount of damage/anxiety
-parker’s study shows that higher anxiety is linked to better recall
-supported Yuille and cutshall but contradicts Yerkes and dodson
what are the strengths?
(support for negative effects)
-valentine and mesout study support weapon focus
-researchers used objective measure of heart rate to divide Ps into high or low anxiety groups
-anxiety clearly disrupted the Ps ability to recall details ab the actor in london dungeon labyrinth
- so high level anxiety in a stressful event impacts recall
(supports for positive effects)
Christianson and Hubinette interviewed 58 witnesses of real bank robberies, including both directly and indirectly involved individuals. They assumed those directly involved would experience higher anxiety. Overall, witnesses had 75% accuracy, with those directly involved recalling more details. This suggests that anxiety can enhance recall.
what were weaknesses?
(unsualness not anxiety)
-johnson and scott may have not measured anxiety
-Ps may have been shocked at what they saw rather than scared
-Pickel conducted a study with scissors, hand gun, wallet or raw chicken in a hair dressing video
-EWT was poorer in situations w the raw chicken and handgun (high unusualness)
-weapon focus affect due to unusualness rather than anxiety
(counterpoint to support for positive effects)
Participants were interviewed months after the event, but researchers had no control over intervening factors like post-event discussions. This means the effects of anxiety could have been influenced by other variables, reducing reliability. The lack of control over confounding factors weakens conclusions, and some evidence contradicts the Yerkes-Dodson law.
(ethical issues)
-scary and traumatising for individuals part of the shooting
-ethically immoral
