[Prediction of epilepsy based on common spatial model algorithm and support vector machine double classification]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2021 Feb 25;38(1):39-46. doi: 10.7507/1001-5515.201911042.
[Article in Chinese]

Abstract

At present the prediction method of epilepsy patients is very time-consuming and vulnerable to subjective factors, so this paper presented an automatic recognition method of epilepsy electroencephalogram (EEG) based on common spatial model (CSP) and support vector machine (SVM). In this method, the CSP algorithm for extracting spatial characteristics was applied to the detection of epileptic EEG signals. However, the algorithm did not consider the nonlinear dynamic characteristics of the signals and ignored the time-frequency information, so the complementary characteristics of standard deviation, entropy and wavelet packet energy were selected for the combination in the feature extraction stage. The classification process adopted a new double classification model based on SVM. First, the normal, interictal and ictal periods were divided into normal and paroxysmal periods (including interictal and ictal periods), and then the samples belonging to the paroxysmal periods were classified into interictal and ictal periods. Finally, three categories of recognition were realized. The experimental data came from the epilepsy study at the University of Bonn in Germany. The average recognition rate was 98.73% in the first category and 99.90% in the second category. The experimental results show that the introduction of spatial characteristics and double classification model can effectively solve the problem of low recognition rate between interictal and ictal periods in many literatures, and improve the identification efficiency of each period, so it provides an effective detecting means for the prediction of epilepsy.

目前癫痫患者的发病预测手段十分耗时且易受主观因素干扰,因此文中提出了一种基于共空间模式算法(CSP)和支持向量机(SVM)二重分类的癫痫发病自动预测方法。此方法将提取空域特征的共空间模式算法应用到癫痫脑电信号检测中,但是该算法未考虑信号的非线性动力学特征且忽略了其时频信息,所以在特征提取阶段选取了标准差、熵和小波包能量这几种互补特征来进行组合。分类过程采取一种基于支持向量机的全新二重分类模式,即将癫痫患者正常期、发作间期和发作期三个阶段分成正常期和准发病期(包括发作间期和发作期)两类进行支持向量机识别,然后对属于准发病期的样本进行发作间期和发作期的分类,最终实现三个时期的分类识别。实验数据来自德国波恩大学的癫痫研究数据库。实验结果显示,第一重分类平均识别率为 98.73%,第二重分类平均识别率可达 99.90%。结果表明,引入空域特征和二重分类模式能够有效解决众多文献中发作间期和发作期识别率不高的问题,提升各个时期的识别效率,为癫痫患者的发病预测提供有效的检测手段。.

Keywords: common spatial model; double classification; epilepsy electrical signal; feature combination; support vector machine.

MeSH terms

  • Algorithms
  • Electroencephalography
  • Epilepsy* / diagnosis
  • Humans
  • Signal Processing, Computer-Assisted
  • Support Vector Machine*

Grants and funding

山东省重大科技创新项目 (2017CXGC1503)