Factors affecting EWT

Factors affecting EWT

1. misleading information

   • leading questions
     • * response bias
       • * subsitution
         • Loftus& Palmer
           • * Laboratory experiment
             • * Filmed events
           • Loftus and Palmer did an experiment to test the affects of leading questions 45 participants watched a clip of a set up car crash and then answered questions about the speed. more specifically how fast the car was going. 5 groups of participants were given a different verb in the critical question: hit, contacted, bumped, collided and smashed. the lighter sounding words such as contacted or bumped produced a lower average speed than collided or smashed. The leading question caused the witnesses to believe that the car was travelling faster than it was.
   • post event discussion
     • * contamination
       • * conformity
         • Gabbert et al.
           • Gabbert et al did an experiment to test post event discussion. paired participants watched a video of the same crime but from different angles so each participant could see parts that the other could not,. both participants dicussed what they had seen on the video before individually completing a recall test. 71% of participants mistakenly recalled aspects that they hadn't seen in the video but had been picked up in post event discussion. in a control group where there was no discussion there was no recall errors.

2. anxiety

   • Positive effects of anxiety
     • Yuiile and Cutshall (1986)
       • a gun shop owner shot a thief dead and there were 21 witnesses and 13 agreed to participate in the study. they were interviewed 4-5 months after the incident and their accounts were compared with the police accounts from the time of the shooting. they also rated how stressed they felt at the time of the incident.
         • the participants who reported the highest levels of stress were the most accurate in their statements 4-5 months later. (about 88% compared to 75% in the less stressed group)
       • higher ecological validity because it is a real life situation but less control.
   • Negative effects of anxiety
     • Johnson and Scott (1976)
       • the participants waited in a room beliveing they were waiting to be a part of a study. each participant heard an argument in the next room and then one of two things happened: either a man then walked through the waiting room holding a pen with grease on his hands (low anxiety) or a noise of breaking glass was heard and then a man walked through the waiting room with a paper knife covered in blood. (high anxiety)
         • 49% of people in the low anxiety condition were able to identify the man
         • only 33% of people in the high anxiety condition were able to recognise the man.
         • in 1998 Pickel did an experiment in a hair salon to test if people focus on the weapon more if they are surpised rather than scared. The low surprise ones were the wallet and the scissors because they are usual everyday items, the participants surprised with these items were more likely to recognise the face of the person. The raw chicken and the handgun were high surprise items as they were unexpected and the people surprised by thus are more likely to focus on the weapon rather than the face.
       • variables are not operationalised and it is about anxiety not surprise.
   • Yerkes- Dodson law: the higher your stress the more disorganised you are. the lower your stress the more passive you are and therefore the best amount of stress for you to have is a medium level.