The benefits of eye-closure on eyewitness memory

Eyewitness memory is not perfect. However, recent research suggests that eyewitnesses remember more about a witnessed event if they close their eyes during the interview. The experiments reported in this thesis investigated applied and theoretical aspects of the eye-closure effect. Experiments 1-2 examined whether the effect extended to recall of violent events. Eye-closure was found to be as beneficial for recall of physiologically arousing violent events as it was for non-violent events, extending the generalisibility of the effect. Experiment 3 examined recall after a delay and repeated recall attempts, and found no benefits of eye-closure during immediate free recall, but substantial benefits in both free and cued recall after one week. Experiments 4-5 examined the theoretical underpinnings of the eye-closure effect. No evidence was found for an “ear-closure” effect on a written recall test. Nevertheless, meaningless visual and auditory distractions during an oral interview impaired recall performance, particularly for information presented in the same modality as the distraction. These impairments could be overcome by eye-closure or, to a lesser extent, by looking at a blank screen. The data were fitted to the newly proposed Cognitive Resources framework, to estimate the relative importance of general and modality-specific processes. Experiment 6 enhanced the ecological validity of the research. A forensically relevant event was staged on the street, after which witnesses were interviewed either in a quiet interview room or on a busy street. Eye-closure had substantial benefits in free recall and helped witnesses to provide detailed correct answers about visual aspects of the event. It was most effective for witnesses interviewed inside, suggesting that mental context reinstatement might play a role in the eye-closure effect. Taken together, the findings suggest that the eye-closure instruction could provide a simple alternative to the Cognitive Interview, particularly when police resources are limited.