Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
Elife. 2022 Mar 30;11:e71309. doi: 10.7554/eLife.71309.
Aversive events sometimes turn into intrusive memories. However, prior evidence indicates that such memories can be controlled via a mechanism of retrieval suppression. Here, we test the hypothesis that suppression exerts a sustained influence on memories by deteriorating their neural representations. This deterioration, in turn, would hinder their subsequent reactivation and thus impoverish the vividness with which they can be recalled. In an fMRI study, participants repeatedly suppressed memories of aversive scenes. As predicted, this process rendered the memories less vivid. Using a pattern classifier, we observed that suppression diminished the neural reactivation of scene information both globally across the brain and locally in the parahippocampal cortices. Moreover, the decline in vividness was associated with reduced reinstatement of unique memory representations in right parahippocampal cortex. These results support the hypothesis that suppression weakens memories by causing a sustained reduction in the potential to reactivate their neural representations.
厌恶事件有时会变成侵入性记忆。然而，先前的证据表明，这种记忆可以通过检索抑制的机制来控制。在这里，我们通过测试抑制通过恶化记忆的神经表征对记忆产生持续影响的假设来验证这一理论。这种恶化反过来又会阻碍它们随后的重新激活，从而减少它们被回忆的生动程度。在一项 fMRI 研究中，参与者反复抑制厌恶场景的记忆。正如预测的那样，这个过程使记忆不那么生动。使用模式分类器，我们观察到抑制不仅在大脑全局范围内，而且在海马旁皮质局部范围内，都降低了场景信息的神经再激活。此外，生动度的下降与右海马旁皮质中独特记忆表征的重新建立减少有关。这些结果支持了这样一种假设，即抑制通过持续降低重新激活其神经表征的能力来削弱记忆。
