Anxiety - EWTs

• Johnson and Scott - anxiety has a negative effect procedure

  participants sat in a waiting room believing they were going to participate in a lab study. each participant heard an argument in the next room. there was a low-anxiety condition (man w greasy hands and a pen) and a high-anxiety condition (shouting, glass breaking, and blood on hands). Participants were then asked to pick the man from a set of photogrpahs
• Johnson and Scott - anxiety has a negative effect findings

  49% of participants in the low anxiety condition were able to identify the man, it was only 33% for the other condition.
• Johnson and Scott - anxiety has a negative effect conclusion 


  the tunnel theory of memory argues that a witness's attention is on the weapon as it is the source of danger and anxiety
• Yuille and Cutshall - anxiety has a positive affect procedure

  in a real crime a gun shop owner shot a thief dead. there were 21 witnesses, and 13 agreed to aid the study. participants were interviwed 4-5 months after the event and accounts were compared to police interviews from the day. witnesses rated how stressed they felt at the time of the incident.
• Yuille and Cutshall - anxiety has a positive effect findings


  witnesses were very accurate and there was little change after five months. some smaller details were less accurate.
• Yuille and Cutshall - anxiety has a positive effect conclusion


  participants who reported the highest levels of stress were most accurate (88%) compared to the less stressed group (75%)
• the 'inverted U' theory 


  yerkes et al. argues that the relationship between performeance and arousal/stress is curvilinear rather than linear
• anxiety affects memory

  deffenbacher found that lower levels of anxiety did produce lower levels of recall accuracy. anxiety increases recall accuracy up to an optimum point, more anxiety than optimum reduces accuracy
• limitation of Johnson and Scott's study

  may test surprise and not anxiety. participants may focus on a weapon as they are surprised by it rather than scared. pickel used scissors, a handgun and raw chicken as handheld items in a hair salon. EWT was poorer for high unusualness. so the weapon focus effect is due to unusualness rather than anxiety so the study is useless
• the inverted u explanation is limited as it is too simplistic


  anxiety is difficult to define and measure as it has four elements. the explanation assumes that one of these elements is linked to poor performance-physiological arousal. so the explanation fails to account for other factors like the effect of the emotional experience of witnessing crime on the accuracy of memory
• demand characteristics may affects lab studies of anxiety

  most participants in controlled labs are aware they're being observed for a study. they may work out that they are going to be asked about what they watched so may try to give more helpful responses that don't help at all. this reduces the validity of the research.