Department of Psychology, Iowa State University, Ames, IA 50011, USA.
J Exp Psychol Appl. 2011 Dec;17(4):418-32. doi: 10.1037/a0025147. Epub 2011 Aug 22.
Eyewitnesses typically recount their experiences many times before trial. Such repeated retrieval can enhance memory retention of the witnessed event. However, recent studies (e.g., Chan, Thomas, & Bulevich, 2009) have found that initial retrieval can exacerbate eyewitness suggestibility to later misleading information--a finding termed retrieval-enhanced suggestibility (RES). Here we examined the influence of multiple retrieval attempts on eyewitness suggestibility to subsequent misinformation. In four experiments, we systematically varied the number of initial tests taken (between zero and six), the delay between initial testing and misinformation exposure (~30 min or 1 week), and whether initial testing was manipulated between- or within-subjects. University undergraduate students were used as participants. Overall, we found that eyewitness suggestibility increased as the number of initial tests increased, but this RES effect was qualified by the delay and by whether initial testing occurred in a within- or between-subjects manner. Specifically, the within-subjects RES effect was smaller than the between-subjects RES effect, possibly because of the influence of retrieval-induced forgetting/facilitation (Chan, 2009) when initial testing was manipulated within subjects. Moreover, consistent with the testing effect literature (Roediger & Karpicke, 2006), the benefits of repeated testing on later memory were stronger after a 1-week delay than after a 30-min delay, thus reducing the negative impact of RES in long-term situations. These findings suggest that conditions that are likely to occur in criminal investigations can either increase (repeated testing) or reduce (delay) the influence of RES, thus further demonstrating the complex relationship between eyewitness memory and repeated retrieval.
目击者通常在审判前多次讲述他们的经历。这种重复检索可以增强目击者对所目击事件的记忆保留。然而，最近的研究（例如 Chan、Thomas 和 Bulevich，2009）发现，最初的检索会加剧目击者对后来误导性信息的易受暗示性——这一发现被称为检索增强的易受暗示性（RES）。在这里，我们研究了多次检索尝试对目击者对后续错误信息的易受暗示性的影响。在四个实验中，我们系统地改变了初始测试的次数（零到六次之间）、初始测试和错误信息暴露之间的延迟（约 30 分钟或 1 周），以及初始测试是在被试间还是被试内进行操作。我们使用大学本科生作为参与者。总的来说，我们发现目击者的易受暗示性随着初始测试次数的增加而增加，但这种 RES 效应受到延迟和初始测试是在被试内还是被试间进行操作的影响。具体来说，被试内的 RES 效应小于被试间的 RES 效应，这可能是因为当初始测试在被试内进行操作时，会受到检索诱导的遗忘/促进的影响（Chan，2009）。此外，与测试效应文献（Roediger 和 Karpicke，2006）一致，重复测试对后续记忆的好处在 1 周延迟后比 30 分钟延迟后更强，从而减少了 RES 在长期情况下的负面影响。这些发现表明，在刑事调查中可能发生的情况既可以增加（重复测试）也可以减少（延迟）RES 的影响，从而进一步证明了目击者记忆和重复检索之间复杂的关系。
