What makes humans unique as a species and as individuals? Our uniqueness stems from language, tool use, reasoning, and other cognitive abilities that are largely mediated by specialized regions of the cerebral cortex. These regions of higher cognitive function have expanded disproportionately during human evolution (compared with nonhuman primates) and during postnatal maturation, when cortical surface area expands threefold between infancy and adulthood (1). Our uniqueness as individuals reflects countless differences in brain structure, function, and connectivity. One basic anatomical difference between similarly aged individuals is a more than 1.5-fold variation in total brain size (and total cortical volume) (2). On page 1222 of this issue, Reardon et al. (3) bring this aspect of individual variability under the umbrella of “differential scaling” by showing that human brains of different sizes do not scale uniformly across all regions. Rather, larger brains show greater expansion in regions associated with higher cognition and less expansion in regions associated with sensory, motor, and limbic (emotion- and affect-related) functions.

中文翻译：

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人脑大小的缩放

是什么让人类作为一个物种和个体独一无二？我们的独特性源于语言、工具使用、推理和其他主要由大脑皮层专门区域介导的认知能力。这些高级认知功能区域在人类进化过程中（与非人类灵长类动物相比）和出生后成熟过程中不成比例地扩大，此时皮质表面积在婴儿期和成年期之间扩大了三倍 (1)。我们作为个体的独特性反映了大脑结构、功能和连通性的无数差异。相似年龄个体之间的一个基本解剖学差异是总大脑大小（和总皮质体积）的差异超过 1.5 倍 (2)。在本期第 1222 页，Reardon 等人。(3) 通过显示不同大小的人脑在所有区域的缩放比例不同，将个体差异的这一方面置于“差异缩放”的保护伞之下。相反，较大的大脑在与较高认知相关的区域中表现出更大的扩张，而在与感觉、运动和边缘系统（情绪和情感相关）功能相关的区域中表现出较少的扩张。