Sinusoidal modeling of ictal activity along a thalamus-to-cortex seizure pathway I: new coherence approaches.
Sinusoidal modeling of ictal activity along a thalamus-to-cortex seizure pathway I: new coherence approaches.
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沿着丘脑到皮质癫痫通路 I 的发作活动的正弦模型：新的一致性方法。
DOI：
10.1114/b:abme.0000039359.65273.9b
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发表时间：
2004
影响因子：
3.8
通讯作者：
Mirski,MarekA
中科院分区：
文献类型：
--
作者：
Sherman,DavidL;Patel,ChiragB;Zhang,Ning;Rossell,LisaAnn;Tsai,YienChe;Thakor,NitishV;Mirski,MarekA
了解神经元回路中的关联对于追踪癫痫通路至关重要。提出了两种测量场电位和EEG通道之间的相干性的新方法，用于对癫痫发作期间通道之间的线性关联水平进行建模。这些方法依赖于将重复性阵挛发作活动建模为具有不同程度锁相的正弦曲线的总和。从相关和互相关时域数据中估计正弦信号的幅度，我们可以从这些幅度的比值中找到相干性。一种方法利用来自多信号分类（MUSIC）技术的幅度发现。另一种方法是利用由互相关矩阵和自相关矩阵组成的矩阵束方程中的单个正弦曲线的幅度及其比值的变化。这些方程的相应广义本征值形成相干比。这利用了使用旋转不变技术（ESPRIT）算法的信号参数的估计，以达到相干幅度比。仿真结果表明，MUSIC方法提供了更好的抗噪性，因为它优于传统的基于傅立叶变换的相干估计方法。两个相干性估计器都反映了沿沿着特定传输路径传播或不传播的正弦分量的存在。我们说明了这两种方法的价值，通过检查癫痫发作脑电图从特定的丘脑核团和皮质在啮齿动物模型的全身性癫痫之间的相关性的强度。戊四氮（PTZ）化学惊厥大鼠模型反映了丘脑前核的选择性激活。使用这两种方法，这个神经元元件与皮质的一致性比另一个丘脑区域，后丘脑大得多（p< 0.05）。这些方法分离出前丘脑在形成发作网络中的独特贡献，并证实了早期的常规或周期图技术。
Understanding associations in neuronal circuitry is critical for tracing epilepsy pathways. Two new methods of measuring coherence between field potentials and EEG channels are proposed for modeling the level of linear association between channels during epileptic seizures. These methods rely upon modeling the repetitive clonic seizure activity as a sum of sinusoids with varying degrees of phase locking. Estimating the amplitude of sinusoids from correlation and cross-correlation time domain data, we can find the coherences from a ratio of these amplitudes. One method utilizes amplitude finding from the multiple signal classification (MUSIC) technique. The other method uses alterations in amplitude of individual sinusoids and their ratios in a matrix pencil equation formed from cross- and auto-correlation matrices. The corresponding generalized eigenvalues of these equations form the coherence ratios. This utilizes the estimation of signal parameters using rotational invariance techniques (ESPRIT) algorithm to arrive at coherence amplitude ratios. Simulations illustrate that the MUSIC method provides better noise immunity as it outperforms the conventional Fourier transform-based method for coherence estimation. Both coherence estimators reflect presence of sinusoidal components that are propagated or not propagated along a particular transmission pathway. We illustrate the value of both methods by examining the strength of correlation between seizure EEG from specific thalamic nuclei and cortex in a rodent model of generalized epilepsy. The pentylenetetrazol (PTZ) chemoconvulsant model in rats reflects selective activation of the anterior thalamic nucleus. Using both methods, this neuronal element has much larger coherence with cortex than another thalamic region, the posterior thalamus (p< 0.05). These methods isolate the unique contribution of anterior thalamus in the formation of an ictal network and corroborate earlier conventional or periodogram techniques.