Heinbockel Hendrik, Leicht Gregor, Wagner Anthony D, Schwabe Lars
Department of Cognitive Psychology, University of Hamburg, Hamburg, Germany.
Department of Psychiatry and Psychotherapy, University Medical Center Hamburg Eppendorf, Hamburg, Germany.
Elife. 2025 Jan 29;13:RP100525. doi: 10.7554/eLife.100525.
When retrieved, seemingly stable memories can become sensitive to significant events, such as acute stress. The mechanisms underlying these memory dynamics remain poorly understood. Here, we show that noradrenergic stimulation after memory retrieval impairs subsequent remembering, depending on hippocampal and cortical signals emerging during retrieval. In a three-day study, we measured brain activity using fMRI during initial encoding, 24 hr-delayed memory cueing followed by pharmacological elevations of glucocorticoid or noradrenergic activity, and final recall. While post-retrieval glucocorticoids did not affect subsequent memory, the impairing effect of noradrenergic arousal on final recall depended on hippocampal reactivation and category-level reinstatement in the ventral temporal cortex during memory cueing. These effects did not require a reactivation of the original memory trace and did not interact with offline reinstatement during rest. Our findings demonstrate that, depending on the retrieval-related neural reactivation of memories, noradrenergic arousal after retrieval can alter the future accessibility of consolidated memories.
当被提取时，看似稳定的记忆会对重大事件（如急性应激）变得敏感。这些记忆动态变化背后的机制仍知之甚少。在这里，我们表明，记忆提取后的去甲肾上腺素能刺激会损害后续的记忆，这取决于提取过程中出现的海马体和皮质信号。在一项为期三天的研究中，我们使用功能磁共振成像（fMRI）测量了初始编码、24小时延迟记忆提示（随后进行糖皮质激素或去甲肾上腺素能活性的药理学升高）以及最终回忆期间的大脑活动。虽然提取后糖皮质激素不影响后续记忆，但去甲肾上腺素能唤醒对最终回忆的损害作用取决于记忆提示期间海马体的重新激活和腹侧颞叶皮质中的类别水平恢复。这些效应不需要重新激活原始记忆痕迹，并且在休息期间不与离线恢复相互作用。我们的研究结果表明，根据与提取相关的记忆神经重新激活，提取后的去甲肾上腺素能唤醒可以改变巩固记忆的未来可及性。
