Brain distributed memory network : Towards the integration of functional imaging study and single-unit neurophysiology.

1. 我们使用4.7T MRI系统（BioSpec47/40; Bruker BioSpin）成功地启动了猕猴脑功能测绘系统。我们现在可以获得整个大脑的单次EPI图像，其平面内空间分辨率为1.25mmx1.5mm。我们发表了许多关于使用该系统对猴子进行功能性核磁共振成像（fMRI）的重要论文（见下文）。我们建立了一种新的方法，直接比较从警觉行为的猴子获得的高级认知任务的激活图和从人类获得的激活图（Nakahara et al., 2002）。它首先应用于研究威斯康星卡片分类测试正确表现的神经机制。它揭示了猴子弓状沟前侧和人类额下回背侧在功能上的同源性。该报告被《科学》杂志2002年第295卷第5559期内封面突出。我们还发现了猴子（如FEF， LIP）和人类（Koyama et al., 2004）的皮层眼动相关区域之间的功能同源性。我们开发了一种新方法，使我们能够使用4.7T MRI系统在100um的空间分辨率下定位猴子大脑中的微电极尖端（Matsui等人，2007）。在这种方法中，磁化率诱导效应增强了微电极尖端的可探测性，而微电极尖端通常只占图像体素体积的百分之几。它开辟了一个新的视角，在灵长类动物大脑皮层层的微电极记录位点的定位允许分析记录的神经元活动和潜在解剖连接之间的关系。我们揭示了认知记忆的以下机制：(1)猴颞下皮层长期联想记忆的前向加工，特别是从TE区到36区联想编码的出现（Naya等，2003）；(2)TE区到36区与长期记忆形成相关的纤维投射的解剖重组（吉田等，2003）；(3)与工作记忆更新相关的前额叶神经元活动（Ohbayashi等，2003）；福岛等人，2004年)和(4)IT皮层联想助记信号的主动维持（Takeda等人，2005年）。我还综合了这些观察结果，并提出了认知记忆系统的整体观点（Miyashita, 2004）。少

1. We successfully launched a functional brain mapping system for macaque monkeys using a 4.7T MRI system (BioSpec47/40; Bruker BioSpin). We can now obtain single-shot EPI images of the entire brain with an in-plane spatial resolution of 1.25mmx1.5mm. We published many important papers (see below) on the functional MRI (fMRI) in monkeys using this system.2. We established a new method which directly compares an activation map obtained from alert behaving monkeys for high-level cognitive tasks with that from humans (Nakahara et al., 2002). It was first applied to the investigation of neural mechanisms underlying correct performance of the Wisconsin Card Sorting Test. It revealed a functional homology between the anterior bank of the arcuate sulcus in monkeys and the dorsal part of the inferior frontal gyrus in humans. This report was highlighted on the inner cover of Science (Vol. 295, No. 5559, 2002). We also identified a functional homology between the cortical eye-movement-related ar … More eas in monkeys (e. g., FEF, LIP) and those in humans (Koyama et al., 2004).3. We developed a novel method that enables us to locate the microelectrode tip in monkey brains at the spatial resolution of 100um using the 4.7T MRI system (Matsui et al., 2007). In this method, the susceptibility-induced effect enhances the detectability of the microelectrode tip, which usually occupies less than a few percent of the volume of an image voxel. It opens a new perspective, in which the localization of microelectrode recording sites in the layers of primate cerebral cortex permits the analysis of relationships between recorded neuronal activities and underlying anatomical connections.4. We revealed the following mechanisms of cognitive memory: (1) forward processing of long-term associative memory in monkey inferotemporal (IT) cortex, particularly, the emergence of associative encoding from area TE to area 36 (Naya et al.,2003), (2) anatomical reorganization of fiber projections from area TE to area 36 related to long-term memory formation (Yoshida et al., 2003), (3) prefrontal neuronal activity related to update of working memory (Ohbayashi et al., 2003; Fukushima et al., 2004), and (4) active maintenance of associative mnemonic signal in IT cortex (Takeda et al., 2005). I also synthesized these observations and proposed a global view of the cognitive memory system (Miyashita, 2004). Less