Factors affecting the accuracy of eyewitness testimony: misleading information, including leading questions and post-event discussion; anxiety.

What this dot point is asking

AQA wants you to explain how misleading information (leading questions and post-event discussion) and anxiety affect the accuracy of eyewitness testimony (EWT). The exam skill is to use Loftus and Palmer precisely, to handle the apparently contradictory anxiety evidence with the Yerkes-Dodson law, and to evaluate the ecological validity of the research.

Misleading information

Misleading information is information that suggests a desired response and can distort a witness's memory. It comes in two forms. Leading questions act through their wording at the point of questioning, as shown by Loftus and Palmer.

There are two competing explanations for the leading-question effect. The response-bias explanation holds that the wording does not change the memory itself but biases the answer the witness gives. The substitution explanation holds that the wording actually alters the stored memory, which is supported by the second part of the study: a week later, participants given the word "smashed" were more likely to report seeing broken glass that was never in the film, suggesting their actual memory had changed. Post-event discussion works differently, contaminating memory after the event. When co-witnesses discuss what they saw, they may incorporate each other's (sometimes mistaken) details into their own accounts, a process called memory conformity, driven by the wish to be socially accepted or the belief that others are right.

Anxiety

Johnson and Scott (1976) found weapon focus reduced accuracy: witnesses who saw a man holding a knife were less accurate at identifying him than those who saw a pen, suggesting anxiety narrows attention. In contrast, Yuille and Cutshall (1986) found witnesses to a real shooting had accurate memories months later, suggesting high anxiety can aid recall.

The Yerkes-Dodson law explains this inverted-U: accuracy is best at moderate arousal and worse at very low or very high arousal.

Anxiety is the factor that produces the most apparently contradictory findings, which makes it ideal for evaluation. The weapon focus effect suggests anxiety harms accuracy by narrowing attention onto the threatening object at the expense of other details, although Pickel argued the effect may be driven by surprise or unusualness (a chicken or a stick of celery produced similar effects) rather than anxiety as such. The real-world shooting study by Yuille and Cutshall points the other way, with highly stressed witnesses giving accurate accounts months later, which has high ecological validity because it concerned a genuine crime. The two findings are reconciled by the Yerkes-Dodson inverted-U: performance and recall accuracy rise with arousal up to an optimum and then fall as arousal becomes extreme, so moderate anxiety aids recall while very high anxiety impairs it. A general limitation across the topic is that many laboratory studies (watching a staged video) lack the emotional impact of a real crime, so they may understate or distort the true effect of anxiety on memory.