Smit Dirk J A, Stam Cornelis J, Posthuma Danielle, Boomsma Dorret I, de Geus Eco J C
Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands.
Hum Brain Mapp. 2008 Dec;29(12):1368-78. doi: 10.1002/hbm.20468.
Recent studies have shown that resting-state functional networks as studied with fMRI, EEG, and MEG may be so-called small-world networks. We investigated to what extent the characteristic features of small-world networks are genetically determined. To represent functional connectivity between brain areas, we measured resting EEG in 574 twins and their siblings and calculated the synchronization likelihood between each pair of electrodes. We applied a threshold to obtain a binary graph from which we calculated the clustering coefficient C (describing local interconnectedness) and average path length L (describing global interconnectedness) for each individual. Modeling of MZ and DZ twin and sibling resemblance indicated that across various frequency bands 46-89% of the individual differences in C and 37-62% of the individual differences in L are heritable. It is asserted that C, L, and a small-world organization are viable markers of genetic differences in brain organization.
最近的研究表明，通过功能磁共振成像（fMRI）、脑电图（EEG）和脑磁图（MEG）研究的静息态功能网络可能是所谓的小世界网络。我们调查了小世界网络的特征在多大程度上是由基因决定的。为了表示脑区之间的功能连接，我们测量了574对双胞胎及其兄弟姐妹的静息脑电图，并计算了每对电极之间的同步可能性。我们应用一个阈值来获得一个二元图，从中我们为每个个体计算聚类系数C（描述局部互连性）和平均路径长度L（描述全局互连性）。同卵双胞胎（MZ）和异卵双胞胎（DZ）以及兄弟姐妹相似性的模型表明，在各个频段中，C的个体差异中有46 - 89%以及L的个体差异中有37 - 62%是可遗传的。有人断言，C、L和小世界组织是脑组织基因差异的可行标记。
