Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA.
Department of Physics, Yale University, New Haven, CT, USA.
Neuron. 2019 Mar 20;101(6):1181-1194.e13. doi: 10.1016/j.neuron.2019.01.017. Epub 2019 Feb 7.
The large-scale organization of dynamical neural activity across cortex emerges through long-range interactions among local circuits. We hypothesized that large-scale dynamics are also shaped by heterogeneity of intrinsic local properties across cortical areas. One key axis along which microcircuit properties are specialized relates to hierarchical levels of cortical organization. We developed a large-scale dynamical circuit model of human cortex that incorporates heterogeneity of local synaptic strengths, following a hierarchical axis inferred from magnetic resonance imaging (MRI)-derived T1- to T2-weighted (T1w/T2w) mapping and fit the model using multimodal neuroimaging data. We found that incorporating hierarchical heterogeneity substantially improves the model fit to functional MRI (fMRI)-measured resting-state functional connectivity and captures sensory-association organization of multiple fMRI features. The model predicts hierarchically organized higher-frequency spectral power, which we tested with resting-state magnetoencephalography. These findings suggest circuit-level mechanisms linking spatiotemporal levels of analysis and highlight the importance of local properties and their hierarchical specialization on the large-scale organization of human cortical dynamics.
皮层中动态神经活动的大规模组织是通过局部回路之间的长程相互作用而出现的。我们假设，大规模动力学也受到皮层区域之间固有局部属性异质性的影响。微电路属性专门化的一个关键轴与皮层组织的层次结构水平有关。我们开发了一个包含局部突触强度异质性的人类皮层大规模动力电路模型，该模型遵循从磁共振成像（MRI）衍生的 T1 到 T2 加权（T1w/T2w）映射推断出的层次轴，并使用多模态神经影像学数据对模型进行拟合。我们发现，包含层次异质性可大大提高模型对功能磁共振成像（fMRI）测量的静息态功能连接的拟合度，并捕获多个 fMRI 特征的感觉关联组织。该模型预测了层次化组织的更高频率谱功率，我们使用静息态脑磁图对其进行了测试。这些发现表明了连接时空分析水平的电路级机制，并强调了局部属性及其层次专业化对人类皮层动力学大规模组织的重要性。
