Our brain has remarkable computational power, generating sophisticated behaviors, storing memories over an individual’s lifetime, and producing higher cognitive functions. However, little of our neuroscience knowledge covers the human brain. Is this organ truly unique, or is it a scaled version of the extensively studied rodent brain? Combining multicellular patch-clamp recording with expansion-based superresolution microscopy and full-scale modeling, we determined the cellular and microcircuit properties of the human hippocampal CA3 region, a fundamental circuit for memory storage. In contrast to neocortical networks, human hippocampal CA3 displayed sparse connectivity, providing a circuit architecture that maximizes associational power. Human synapses showed unique reliability, high precision, and long integration times, exhibiting both species- and circuit-specific properties. Together with expanded neuronal numbers, these circuit characteristics greatly enhanced the memory storage capacity of CA3. Our results reveal distinct microcircuit properties of the human hippocampus and begin to unravel the inner workings of our most complex organ.

中文翻译：

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人类海马 CA3 使用特定的功能连接规则实现高效的联想记忆


我们的大脑具有非凡的计算能力，可以产生复杂的行为，存储个人一生的记忆，并产生更高的认知功能。然而，我们的神经科学知识很少涵盖人脑。这个器官真的是独一无二的，还是它是被广泛研究的啮齿动物大脑的缩放版本？将多细胞膜片钳记录与基于扩展的超分辨率显微镜和全尺寸建模相结合，我们确定了人类海马 CA3 区域的细胞和微电路特性，这是内存存储的基本电路。与新皮层网络相比，人类海马 CA3 表现出稀疏的连接性，提供了一种最大化关联能力的电路架构。人类突触表现出独特的可靠性、高精度和较长的积分时间，表现出物种特异性和电路特异性。这些电路特性与神经元数量的扩展一起，大大增强了 CA3 的内存存储容量。我们的结果揭示了人类海马体独特的微回路特性，并开始解开我们最复杂器官的内部运作。