Center on Autobiographical Memory Research, Aarhus University, Aarhus, Denmark.
J Exp Psychol Gen. 2013 May;142(2):426-44. doi: 10.1037/a0029128. Epub 2012 Jul 2.
Involuntary episodic memories are memories of events that come to mind spontaneously, that is, with no preceding retrieval attempts. They are common in daily life and observed in a range of clinical disorders in the form of negative, intrusive recollections or flashbacks. However, little is known about their underlying mechanisms. Here we report a series of experiments in which-for the first time-the activation of involuntary memories is controlled and predicted on the basis of manipulations done at encoding. During encoding, participants were presented with pictures of scenes paired with sounds. Both scene and sound could be either unique (derived from a category that was presented only once) or repeated (derived from a category that was presented several times). During retrieval, the participants conducted an attention-demanding sound location task employing sounds from the encoding phase. In addition to the sound location task, they were asked to record all memories that might spontaneously arise during this task. Unique sounds generated most involuntary memories, consistent with the notion of cue overload. Repeated sounds rarely generated involuntary memories, but often yielded memories of repeated scenes in a voluntary (strategic) recall condition. Retrieval times were lower for involuntary than for comparable samples of strategically retrieved memories, suggesting less executive control involved in involuntary recall. Our findings show that it is possible to control the activation of involuntary episodic memories of daily scenes on the basis of well-known mechanisms of associative memory.
非自愿的情景记忆是指那些自发出现在脑海中的事件记忆，也就是说，没有事先的检索尝试。它们在日常生活中很常见，并且在一系列临床障碍中以负面的、侵入性的回忆或闪回的形式出现。然而，对于它们的潜在机制，我们知之甚少。在这里，我们报告了一系列实验，这些实验首次基于编码阶段的操作来控制和预测非自愿记忆的激活。在编码过程中，参与者会看到场景图片，并配以声音。场景和声音都可以是独特的（来自只出现过一次的类别），也可以是重复的（来自多次出现的类别）。在检索过程中，参与者进行了一项需要注意力的声音位置任务，使用编码阶段的声音。除了声音位置任务外，他们还被要求记录在此任务中可能自发出现的所有记忆。独特的声音产生了大多数非自愿记忆，这与提示过载的概念一致。重复的声音很少产生非自愿记忆，但在自愿（策略性）回忆条件下，经常会产生重复场景的记忆。与策略性检索记忆的可比样本相比，非自愿回忆的检索时间更短，这表明非自愿回忆涉及的执行控制较少。我们的发现表明，基于联想记忆的已知机制，有可能控制日常情景的非自愿情景记忆的激活。
