Anxiety

Anxiety: A state of emotional and physical unpleasant arousal. The emotions include having worried thoughts and feelings of tension. Physical changes include an increased heart rate and sweatiness. Anxiety is a normal reaction to stressful situations, but it can affect the accuracy and detail of eyewitness testimony.

Johnson and Scott (1976): Led participants to believe they were going to be part of a lab study and while seated in a waiting room participants heard an argument next door. In the 'low anxiety' condition a man walked through the door carrying a greasy pen. In the 'high anxiety' group saw a man with a bloody knife. 49% of the 'low anxiety' group correctly identified the man but only 33% of the 'high anxiety' group correctly identified the man.

Tunnel Theory of Memory: Argues that people have enhanced memory for central events which can result in the weapons focus effect.

Yuille and Cutshall (1986): 13 witnesses to a real-life shooting were interviewed 4-5 months post-event and were asked to rate their stress on a 7-point scale and whether they had experienced emotional problems since. Their testimonies were compared with their original police interview and those reported being most stressed were 88% accurate compared to 75% for the low-stress group.

Yerkes-Dodson Law: The inverted-theory states that performance will increase with stress, but only to a certain point, where it decreases dramatically.

Deffenbacher (1983): Reviewed 21 studies of EWT and found lower levels of anxiety produce lower levels of recall accuracy but memory becomes more accurate as the anxiety levels increase. However, there comes a point where the optimal level of anxiety is reached. This is the point of maximum accuracy. If an eyewitness experiences more stress than this, accuracy decreases dramatically.

Limitation of Johnson and Scott: Johnson and Scott may not have tested anxiety but instead the participants focused on the weapon because they were surprised by it more than scared. Pickel (1998) replicated Johnson and Scott's study using unusual items (such as raw chicken) and showed that Eyewitnesses recall was worse in the high unusualness conditions (chicken + handgun). Suggests the Weapons Focus Effect is due to unusualness and not anxiety.

Evidence Support for Negative Effects of Anxiety: Valentine and Mesout (2009) investigated how stress and anxiety levels affect eyewitness identification. Found that only 30% of participants that scored above the median state anxiety correctly identified the 'scary' person in comparison to 75% of participants who scored below the median state anxiety level who correctly identified the 'scary' person.

Evidence Showing Positive Effects of Anxiety: Christianson and Hubinette (1993) questioned 58 witnesses to real bank robberies. Some were onlookers, others were employees who were directly threatened. Recall was more than 75% accurate across all witnesses and direct witnesses were even more accurate.

Limitation of Christianson and Hubinette: They interviewed participants 4 - 15 months post-event and had no control over what happened to their participants in the intervening time. The effects of anxiety may have been overwhelmed by these other factors and impossible to assess by the time participants were interviewed.