期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2014
卷号：111
期号：46
页码：16580-16585
DOI：10.1073/pnas.1414153111
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificanceThe cerebral cortex can be divided into a number of distinct areas on the basis of anatomy and function. Understanding the complex pattern of connections among these areas is essential to uncovering how the brain performs its distributed computations. We report a systematic relation between the connectivity and functional similarity of cortical areas in the monkey, human, and mouse cortex. Motivated by observations that the cortical areal network is densely connected and that connections have a strong dependence on wiring length, we introduce a spatially embedded, generative model of the areal network that accounts for many observed features of cortical connectivity. Recent anatomical tracing studies have yielded substantial amounts of data on the areal connectivity underlying distributed processing in cortex, yet the fundamental principles that govern the large-scale organization of cortex remain unknown. Here we show that functional similarity between areas as defined by the pattern of shared inputs or outputs is a key to understanding the areal network of cortex. In particular, we report a systematic relation in the monkey, human, and mouse cortex between the occurrence of connections from one area to another and their similarity distance. This characteristic relation is rooted in the wiring distance dependence of connections in the brain. We introduce a weighted, spatially embedded random network model that robustly gives rise to this structure, as well as many other spatial and topological properties observed in cortex. These include features that were not accounted for in any previous model, such as the wide range of interareal connection weights. Connections in the model emerge from an underlying distribution of spatially embedded axons, thereby integrating the two scales of cortical connectivity--individual axons and interareal pathways--into a common geometric framework. These results provide insights into the origin of large-scale connectivity in cortex and have important implications for theories of cortical organization.
关键词：cortex ; large scale ; complex network ; monkey ; model
