Center for Neuroscience, University of California, Davis, CA 95616;
Center for Neuroscience, University of California, Davis, CA 95616.
Proc Natl Acad Sci U S A. 2018 Oct 23;115(43):11084-11089. doi: 10.1073/pnas.1800006115. Epub 2018 Oct 8.
Remembering is a complex process that involves recalling specific details, such as who you were with when you celebrated your last birthday, as well as contextual information, such as the place where you celebrated. It is well established that the act of remembering enhances long-term retention of the retrieved information, but the neural and cognitive mechanisms that drive memory enhancement are not yet understood. One possibility is that the process of remembering results in reactivation of the broader episodic context. Consistent with this idea, in two experiments, we found that multiple retrieval attempts enhanced long-term retention of both the retrieved object and the nontarget object that shared scene context, compared with a restudy control. Using representational similarity analysis of fMRI data in experiment 2, we found that retrieval resulted in greater neural reactivation of both the target objects and contextually linked objects compared with restudy. Furthermore, this reactivation occurred in a network of medial and lateral parietal lobe regions that have been linked to episodic recollection. The results demonstrate that retrieving a memory can enhance retention of information that is linked in the broader event context and the hippocampus and a posterior medial network of parietal cortical areas (also known as the Default Network) play complementary roles in supporting the reactivation of episodically linked information during retrieval.
记忆是一个复杂的过程，涉及回忆特定的细节，例如你上次生日是和谁一起庆祝的，以及上下文信息，例如你在哪里庆祝的。人们已经充分认识到，记忆的行为可以增强检索到的信息的长期保留，但驱动记忆增强的神经和认知机制尚不清楚。一种可能性是，记忆的过程导致更广泛的情景上下文的重新激活。为了验证这一观点，在两项实验中，我们发现与重新学习控制组相比，多次检索尝试可以增强检索对象和共享场景上下文的非目标对象的长期保留。在实验 2 中，我们使用 fMRI 数据的代表性相似性分析发现，与重新学习相比，检索会导致目标对象和上下文相关对象的神经再激活更大。此外，这种再激活发生在与情景回忆相关的内侧和外侧顶叶区域的网络中。研究结果表明，检索记忆可以增强与更广泛的事件背景以及海马体相关联的信息的保留，并且顶叶皮质区域（也称为默认网络）的后内侧网络在后内侧网络中发挥互补作用，以支持在检索过程中与情景相关联的信息的再激活。
