University College London Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, United Kingdom.
Proc Natl Acad Sci U S A. 2009 Dec 1;106(48):20493-8. doi: 10.1073/pnas.0904823106. Epub 2009 Nov 16.
Recent studies in humans and animals raise the possibility that actively maintaining a detailed memory of a scene within working memory may require the hippocampus, a brain structure better known for its role in long-term memory. We show that the hippocampus is behaviorally and functionally critical for configural-relational (CR) maintenance by orchestrating the synchrony of occipital and temporal brain regions in the theta-frequency range. Using magnetoencephalography in healthy adults and patients with bilateral hippocampal sclerosis, we distinguish this hippocampus-dependent theta-network from one that is independent of the hippocampus and used for non-CR scene maintenance. This non-CR theta-network involved frontal and parietal brain regions. We also show that the functional and topographical dissociation between these two networks cannot be accounted for by perceptual difficulty or the amount of information to be maintained ("load"). Also, we confirm in healthy adults that active maintenance of the CR arrangement of objects within a scene is impaired by task-interference during the delay in a manner akin to working-memory maintenance processes. Together, these findings demand reconsideration of the classical functional-anatomical distinctions between long- and short-term memory.
最近在人类和动物身上进行的研究提出了一种可能性，即在工作记忆中主动地详细记住一个场景可能需要海马体，而海马体在长期记忆中的作用更为人所熟知。我们表明，海马体通过协调θ频带内枕叶和颞叶脑区的同步性，在组态关系（CR）维持方面具有行为和功能上的关键性。我们使用健康成年人和双侧海马硬化症患者的脑磁图，将这种依赖于海马体的θ网络与不依赖于海马体、用于非 CR 场景维持的网络区分开来。这种非 CR 的θ网络涉及到额叶和顶叶脑区。我们还表明，这两个网络之间的功能和拓扑分离不能用感知难度或需要维持的信息量（“负载”）来解释。此外，我们在健康成年人中证实，在延迟期间，任务干扰会以类似于工作记忆维持过程的方式损害对场景中对象的 CR 排列的主动维持。这些发现共同要求重新考虑长期和短期记忆之间的经典功能-解剖学区别。
