Elevated Stress Impairs The Accuracy Of Eyewitness Memory But Not The Confidence-Accuracy Relationship

Although numerous studies have identified factors that affect eyewitness identification accuracy, recent studies report that many of these factors do not affect the accuracy of high-confidence identifications. This is critical because legal cases are more likely to be prosecuted if they involve high-confidence eyewitnesses. Using a confidence-accuracy characteristic (CAC) analysis, we explored whether stress affects the accuracy of high-confidence identifications. In two experiments, people viewed faces followed by an old/new recognition-memory test and provided confidence ratings. Stress was manipulated by pairing a low- or high-valence image with each studied face. Identification accuracy was higher in the low- than high-stress condition, yet the proportion correct for high-confidence positive identifications was similar in the two stress conditions. Elevated stress impairs eyewitness identification accuracy overall. However, the results of this study suggest that confidence is a better predictor of recognition-memory accuracy than is stress even though confidence alone is still an imperfect predictor.