Departamento de Psiquiatría y Psicología Médica, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain.
Neuroimage. 2011 Aug 15;57(4):1300-7. doi: 10.1016/j.neuroimage.2011.05.079. Epub 2011 Jun 12.
The advent of new signal processing methods, such as non-linear analysis techniques, represents a new perspective which adds further value to brain signals' analysis. Particularly, Lempel-Ziv's Complexity (LZC) has proven to be useful in exploring the complexity of the brain electromagnetic activity. However, an important problem is the lack of knowledge about the physiological determinants of these measures. Although a correlation between complexity and connectivity has been proposed, this hypothesis was never tested in vivo. Thus, the correlation between the microstructure of the anatomic connectivity and the functional complexity of the brain needs to be inspected. In this study we analyzed the correlation between LZC and fractional anisotropy (FA), a scalar quantity derived from diffusion tensors that is particularly useful as an estimate of the functional integrity of myelinated axonal fibers, in a group of sixteen healthy adults (all female, mean age 65.56±6.06 years, intervals 58-82). Our results showed a positive correlation between FA and LZC scores in regions including clusters in the splenium of the corpus callosum, cingulum, parahipocampal regions and the sagittal stratum. This study supports the notion of a positive correlation between the functional complexity of the brain and the microstructure of its anatomical connectivity. Our investigation proved that a combination of neuroanatomical and neurophysiological techniques may shed some light on the underlying physiological determinants of brain's oscillations.
新信号处理方法的出现，如非线性分析技术，为脑信号分析提供了新的视角，进一步增加了其价值。特别是，Lempel-Ziv 的复杂度（LZC）已被证明在探索脑电磁活动的复杂性方面很有用。然而，一个重要的问题是缺乏对这些测量方法的生理决定因素的了解。虽然已经提出了复杂度和连通性之间的相关性，但这一假设从未在体内进行过测试。因此，需要检查解剖连通性的微观结构和大脑功能复杂性之间的相关性。在这项研究中，我们分析了在一组 16 名健康成年人（均为女性，平均年龄 65.56±6.06 岁，年龄范围为 58-82 岁）中，LZC 与分数各向异性（FA）之间的相关性，FA 是从扩散张量中得出的标量，特别有助于估计髓鞘化轴突纤维的功能完整性。我们的结果表明，在胼胝体体部的压部、扣带、海马旁区和矢状层的簇中，FA 和 LZC 评分之间存在正相关。这项研究支持了大脑功能复杂性与其解剖连通性的微观结构之间存在正相关的观点。我们的研究证明，神经解剖学和神经生理学技术的结合可能有助于揭示大脑振荡的潜在生理决定因素。
