1 School of Information Science and Engineering, Shandong University, Jinan 250100, P. R. China.
2 Suzhou Institute of Shandong University, Suzhou 215123, P. R. China.
Int J Neural Syst. 2016 May;26(3):1650011. doi: 10.1142/S0129065716500118. Epub 2016 Jan 10.
Epileptic seizure detection plays an important role in the diagnosis of epilepsy and reducing the massive workload of reviewing electroencephalography (EEG) recordings. In this work, a novel algorithm is developed to detect seizures employing log-Euclidean Gaussian kernel-based sparse representation (SR) in long-term EEG recordings. Unlike the traditional SR for vector data in Euclidean space, the log-Euclidean Gaussian kernel-based SR framework is proposed for seizure detection in the space of the symmetric positive definite (SPD) matrices, which form a Riemannian manifold. Since the Riemannian manifold is nonlinear, the log-Euclidean Gaussian kernel function is applied to embed it into a reproducing kernel Hilbert space (RKHS) for performing SR. The EEG signals of all channels are divided into epochs and the SPD matrices representing EEG epochs are generated by covariance descriptors. Then, the testing samples are sparsely coded over the dictionary composed by training samples utilizing log-Euclidean Gaussian kernel-based SR. The classification of testing samples is achieved by computing the minimal reconstructed residuals. The proposed method is evaluated on the Freiburg EEG dataset of 21 patients and shows its notable performance on both epoch-based and event-based assessments. Moreover, this method handles multiple channels of EEG recordings synchronously which is more speedy and efficient than traditional seizure detection methods.
癫痫发作检测在癫痫诊断和减少脑电图 (EEG) 记录审查的大量工作量方面起着重要作用。在这项工作中,开发了一种新算法,用于在长期 EEG 记录中使用基于对数欧几里得高斯核的稀疏表示 (SR) 来检测癫痫发作。与传统的欧几里得空间中基于向量数据的 SR 不同,提出了基于对数欧几里得高斯核的 SR 框架,用于在对称正定 (SPD) 矩阵的空间中检测癫痫发作,该空间形成了黎曼流形。由于黎曼流形是非线性的,因此应用对数欧几里得高斯核函数将其嵌入到用于执行 SR 的再生核希尔伯特空间 (RKHS) 中。将所有通道的 EEG 信号划分为时段,并通过协方差描述符生成表示 EEG 时段的 SPD 矩阵。然后,利用基于对数欧几里得高斯核的 SR,对由训练样本组成的字典中的测试样本进行稀疏编码。通过计算最小重构残差来实现对测试样本的分类。该方法在 21 名患者的弗莱堡 EEG 数据集上进行了评估,在基于时段和基于事件的评估中均表现出了显著的性能。此外,该方法可以同步处理多个 EEG 记录通道,比传统的癫痫发作检测方法更快、更高效。