Accuracy of eyewitness testimony: Anxiety

Anxiety neg effect on memory + performance. Automatic skills not affected by stress/physiological arousal, but performance on complicated cognitive tasks reduced by stress.

Why anxiety might reduce accuracy of EWT - weapon focus effect - view that weapon in criminal's hand distracts attention (b/c of anxiety created) from other features -> reduced accuracy of identification.

Participants in waiting room, heard argument in next room, saw man run through room w/ pen covered in grease or knife covered in blood. Asked to identify man from photos.

Supported weapon focus effect. Pen condition 49% accuracy, knife condition 33% accuracy. Loftus et al (1987) - anxiety focuses attention on central features of crime. Researchers monitored eyewitnesses' eye movements, found presence of weapon cause attention to be drawn to weapon, away from other things eg person's face.

Evolutionary argument - suggests adaptive to remember events emotionally important so can identiy similar situations in future, recall how to respons.

Christianson + Hubinette (1993) - evidence of enhanced recall when questioned 58 real witnesses - bank robberies, Sweden. Either victims (bank teller, high anxiety) or bystanders (employee/customer, low anxiety). Interviews 4-15 months after robberies. Found all witnesses good memories for details (75% accurate recall) - most anxious had best recall. 

Christianson (1992) - review of research, concluded memory for neg emotional events better for neutral events, at least for central details.

Deffenbacher (1983) - reviewed 21 studies of effects of anxiety on EWT. Found 10 of studies results linking higher arousal levels to increased EW accuracy, 11 showed opp.

D suggests Yerkes-Dodson effect can acc for apparent inconsistency - would be occasions when anxiety/arousal only moderate, EWT would be enhances. When too extreme, reduced.

Christianson + Hubinette - context of reak crime. Representable.

Fazey + Hardy (1988) more complex relationshop b/ween anxiety + performance than Yerkes-Dodson model. Catastophe theory predicts when physiological arousal increases beyond optimum level, inverted-U hypothesis predicts gradual decrease in performance. However, F + H observed fact there's soemtimes catastropic decline, suggest due to increased mental anxiety - inverted-U only described increase. Deffenbacher et al (2004) believes better fit w/ research findings.

Pickel (1998) - reduced accuracy due to weapon focus effect could be due to surprise, not anxiety. Arranged for participants to watch thief enter hairdressing salon w/ scissors (high threat, low surprise), handgun (high threat, high surprise), wallet (low threat, low surprise) or whole raw chicken (low threat, low surprise). Identification least accurate in high surprise conditions rather than high threat - supports WFE due to surprise, not anxiety.

Individual diffs - emotional sensitivy. Bothwell (1987) - participants assessed for neuroticism - labelled 'neurotic' or 'stable'. Stable showed rising levels accuracy as stress increase, opposite for neurotics - accuracy decreased as stress increased. 

No simple conclusion. Halford + Milne (2005) found victims more accurate in recall of violent crime scene info than non-violent. SHows no simple rule about effect of anxiety on accuracy of EWT as some showed opp.