Department of Cognitive Psychology, Ruhr-University Bochum, Germany.
Neurobiol Learn Mem. 2013 Jan;99:38-49. doi: 10.1016/j.nlm.2012.11.001. Epub 2012 Nov 21.
After reactivation, apparently stable memories can become sensitive to modifications again, requiring another phase of stabilization, called reconsolidation. Recent evidence shows that repeated reactivations strengthen memories and that stronger memories are more resistant to alterations during reconsolidation. Therefore, we asked whether multiple reactivations make memories less vulnerable to manipulations during reconsolidation and thus serve as boundary condition on memory reconsolidation. In Experiment1, we tested whether new learning after the reactivation of previously learned material alters the subsequent memory for the original material. Participants learned negative and neutral pictures, reactivated them 1week later, and learned new pictures immediately thereafter. Memory for the original pictures was assessed in a recognition test 1day later. We found that new learning after reactivation reduced the subsequent memory of the original pictures; new learning alone or reactivation alone, however, had no effect on memory. Two further experiments investigated the impact of multiple reactivations on this memory impairing effect of new learning after reactivation. These experiments showed that the influence of new learning after reactivation disappeared neither after one (Experiment2) nor after three (Experiment3) additional reactivations completely, indicating that even after multiple reactivations memories remain sensitive to modifications during reconsolidation. These findings may have important implications for novel treatment approaches that aim for modification of unwanted memories during reconsolidation.
重新激活后，原本稳定的记忆可能会再次变得敏感，需要经历另一个稳定阶段，即再巩固。最近的证据表明，重复激活可以增强记忆，而更强的记忆在再巩固过程中更能抵抗改变。因此，我们想知道多次重新激活是否会使记忆在再巩固过程中不易受到操纵，从而成为记忆再巩固的边界条件。在实验 1 中，我们测试了在重新激活先前学习过的材料后进行新的学习是否会改变对原始材料的后续记忆。参与者学习了消极和中性的图片，一周后对其进行了重新激活，然后立即学习了新的图片。一天后，在识别测试中评估了对原始图片的记忆。我们发现，重新激活后进行新的学习会降低对原始图片的后续记忆；然而，单独进行新的学习或单独进行重新激活对记忆没有影响。另外两个实验研究了多次重新激活对重新激活后新学习对这种记忆损害效应的影响。这些实验表明，即使经过多次重新激活，重新激活后新学习的影响也不会完全消失（实验 2）或完全消失（实验 3），这表明即使经过多次重新激活，记忆在再巩固过程中仍然对修改敏感。这些发现可能对旨在在再巩固过程中修改不良记忆的新治疗方法具有重要意义。
